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Snake in Matrix
Easy
<p>There is a snake in an <code>n x n</code> matrix <code>grid</code> and can move in <strong>four possible directions</strong>. Each cell in the <code>grid</code> is identified by the position: <code>grid[i][j] = (i * n) + j</code>.</p> <p>The snake starts at cell 0 and follows a sequence of commands.</p> <p>You are given an integer <code>n</code> representing the size of the <code>grid</code> and an array of strings <code>commands</code> where each <code>command[i]</code> is either <code>&quot;UP&quot;</code>, <code>&quot;RIGHT&quot;</code>, <code>&quot;DOWN&quot;</code>, and <code>&quot;LEFT&quot;</code>. It&#39;s guaranteed that the snake will remain within the <code>grid</code> boundaries throughout its movement.</p> <p>Return the position of the final cell where the snake ends up after executing <code>commands</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 2, commands = [&quot;RIGHT&quot;,&quot;DOWN&quot;]</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></p> <p><strong>Explanation:</strong></p> <div style="display:flex; gap: 12px;"> <table border="1" cellspacing="3" style="border-collapse: separate; text-align: center;"> <tbody> <tr> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid red; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">0</td> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #b30000; --darkreader-inline-border-right: #b30000; --darkreader-inline-border-bottom: #b30000; --darkreader-inline-border-left: #b30000;">1</td> </tr> <tr> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">2</td> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #b30000; --darkreader-inline-border-right: #b30000; --darkreader-inline-border-bottom: #b30000; --darkreader-inline-border-left: #b30000;">3</td> </tr> </tbody> </table> <table border="1" cellspacing="3" style="border-collapse: separate; text-align: center;"> <tbody> <tr> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">0</td> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid red; --darkreader-inline-border-top: #b30000; --darkreader-inline-border-right: #b30000; --darkreader-inline-border-bottom: #b30000; --darkreader-inline-border-left: #b30000;">1</td> </tr> <tr> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">2</td> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #b30000; --darkreader-inline-border-right: #b30000; --darkreader-inline-border-bottom: #b30000; --darkreader-inline-border-left: #b30000;">3</td> </tr> </tbody> </table> <table border="1" cellspacing="3" style="border-collapse: separate; text-align: center;"> <tbody> <tr> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">0</td> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #b30000; --darkreader-inline-border-right: #b30000; --darkreader-inline-border-bottom: #b30000; --darkreader-inline-border-left: #b30000;">1</td> </tr> <tr> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">2</td> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid red; --darkreader-inline-border-top: #b30000; --darkreader-inline-border-right: #b30000; --darkreader-inline-border-bottom: #b30000; --darkreader-inline-border-left: #b30000;">3</td> </tr> </tbody> </table> </div> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 3, commands = [&quot;DOWN&quot;,&quot;RIGHT&quot;,&quot;UP&quot;]</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <div style="display:flex; gap: 12px;"> <table border="1" cellspacing="3" style="border-collapse: separate; text-align: center;"> <tbody> <tr> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid red; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">0</td> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #b30000; --darkreader-inline-border-right: #b30000; --darkreader-inline-border-bottom: #b30000; --darkreader-inline-border-left: #b30000;">1</td> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">2</td> </tr> <tr> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">3</td> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #b30000; --darkreader-inline-border-right: #b30000; --darkreader-inline-border-bottom: #b30000; --darkreader-inline-border-left: #b30000;">4</td> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #b30000; --darkreader-inline-border-right: #b30000; --darkreader-inline-border-bottom: #b30000; --darkreader-inline-border-left: #b30000;">5</td> </tr> <tr> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">6</td> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">7</td> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">8</td> </tr> </tbody> </table> <table border="1" cellspacing="3" style="border-collapse: separate; text-align: center;"> <tbody> <tr> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">0</td> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #b30000; --darkreader-inline-border-right: #b30000; --darkreader-inline-border-bottom: #b30000; --darkreader-inline-border-left: #b30000;">1</td> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">2</td> </tr> <tr> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid red; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">3</td> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #b30000; --darkreader-inline-border-right: #b30000; --darkreader-inline-border-bottom: #b30000; --darkreader-inline-border-left: #b30000;">4</td> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #b30000; --darkreader-inline-border-right: #b30000; --darkreader-inline-border-bottom: #b30000; --darkreader-inline-border-left: #b30000;">5</td> </tr> <tr> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">6</td> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">7</td> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">8</td> </tr> </tbody> </table> <table border="1" cellspacing="3" style="border-collapse: separate; text-align: center;"> <tbody> <tr> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">0</td> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">1</td> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">2</td> </tr> <tr> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">3</td> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid red; --darkreader-inline-border-top: #b30000; --darkreader-inline-border-right: #b30000; --darkreader-inline-border-bottom: #b30000; --darkreader-inline-border-left: #b30000;">4</td> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #b30000; --darkreader-inline-border-right: #b30000; --darkreader-inline-border-bottom: #b30000; --darkreader-inline-border-left: #b30000;">5</td> </tr> <tr> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">6</td> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #b30000; --darkreader-inline-border-right: #b30000; --darkreader-inline-border-bottom: #b30000; --darkreader-inline-border-left: #b30000;">7</td> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">8</td> </tr> </tbody> </table> <table border="1" cellspacing="3" style="border-collapse: separate; text-align: center;"> <tbody> <tr> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">0</td> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid red; --darkreader-inline-border-top: #b30000; --darkreader-inline-border-right: #b30000; --darkreader-inline-border-bottom: #b30000; --darkreader-inline-border-left: #b30000;">1</td> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">2</td> </tr> <tr> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">3</td> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #b30000; --darkreader-inline-border-right: #b30000; --darkreader-inline-border-bottom: #b30000; --darkreader-inline-border-left: #b30000;">4</td> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #b30000; --darkreader-inline-border-right: #b30000; --darkreader-inline-border-bottom: #b30000; --darkreader-inline-border-left: #b30000;">5</td> </tr> <tr> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">6</td> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">7</td> <td data-darkreader-inline-border-bottom="" data-darkreader-inline-border-left="" data-darkreader-inline-border-right="" data-darkreader-inline-border-top="" style="padding: 5px 10px; border: 1px solid black; --darkreader-inline-border-top: #8c8273; --darkreader-inline-border-right: #8c8273; --darkreader-inline-border-bottom: #8c8273; --darkreader-inline-border-left: #8c8273;">8</td> </tr> </tbody> </table> </div> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= n &lt;= 10</code></li> <li><code>1 &lt;= commands.length &lt;= 100</code></li> <li><code>commands</code> consists only of <code>&quot;UP&quot;</code>, <code>&quot;RIGHT&quot;</code>, <code>&quot;DOWN&quot;</code>, and <code>&quot;LEFT&quot;</code>.</li> <li>The input is generated such the snake will not move outside of the boundaries.</li> </ul>
Array; String; Simulation
TypeScript
function finalPositionOfSnake(n: number, commands: string[]): number { let [x, y] = [0, 0]; for (const c of commands) { c[0] === 'U' && x--; c[0] === 'D' && x++; c[0] === 'L' && y--; c[0] === 'R' && y++; } return x * n + y; }
3,249
Count the Number of Good Nodes
Medium
<p>There is an <strong>undirected</strong> tree with <code>n</code> nodes labeled from <code>0</code> to <code>n - 1</code>, and rooted at node <code>0</code>. You are given a 2D integer array <code>edges</code> of length <code>n - 1</code>, where <code>edges[i] = [a<sub>i</sub>, b<sub>i</sub>]</code> indicates that there is an edge between nodes <code>a<sub>i</sub></code> and <code>b<sub>i</sub></code> in the tree.</p> <p>A node is <strong>good</strong> if all the <span data-keyword="subtree">subtrees</span> rooted at its children have the same size.</p> <p>Return the number of <strong>good</strong> nodes in the given tree.</p> <p>A <strong>subtree</strong> of <code>treeName</code> is a tree consisting of a node in <code>treeName</code> and all of its descendants.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">edges = [[0,1],[0,2],[1,3],[1,4],[2,5],[2,6]]</span></p> <p><strong>Output:</strong> <span class="example-io">7</span></p> <p><strong>Explanation:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3200-3299/3249.Count%20the%20Number%20of%20Good%20Nodes/images/tree1.png" style="width: 360px; height: 158px;" /> <p>All of the nodes of the given tree are good.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">edges = [[0,1],[1,2],[2,3],[3,4],[0,5],[1,6],[2,7],[3,8]]</span></p> <p><strong>Output:</strong> <span class="example-io">6</span></p> <p><strong>Explanation:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3200-3299/3249.Count%20the%20Number%20of%20Good%20Nodes/images/screenshot-2024-06-03-193552.png" style="width: 360px; height: 303px;" /> <p>There are 6 good nodes in the given tree. They are colored in the image above.</p> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">edges = [[0,1],[1,2],[1,3],[1,4],[0,5],[5,6],[6,7],[7,8],[0,9],[9,10],[9,12],[10,11]]</span></p> <p><strong>Output:</strong> <span class="example-io">12</span></p> <p><strong>Explanation:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3200-3299/3249.Count%20the%20Number%20of%20Good%20Nodes/images/rob.jpg" style="width: 450px; height: 277px;" /> <p>All nodes except node 9 are good.</p> </div> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= n &lt;= 10<sup>5</sup></code></li> <li><code>edges.length == n - 1</code></li> <li><code>edges[i].length == 2</code></li> <li><code>0 &lt;= a<sub>i</sub>, b<sub>i</sub> &lt; n</code></li> <li>The input is generated such that <code>edges</code> represents a valid tree.</li> </ul>
Tree; Depth-First Search
C++
class Solution { public: int countGoodNodes(vector<vector<int>>& edges) { int n = edges.size() + 1; vector<int> g[n]; for (const auto& e : edges) { int a = e[0], b = e[1]; g[a].push_back(b); g[b].push_back(a); } int ans = 0; auto dfs = [&](this auto&& dfs, int a, int fa) -> int { int pre = -1, cnt = 1, ok = 1; for (int b : g[a]) { if (b != fa) { int cur = dfs(b, a); cnt += cur; if (pre < 0) { pre = cur; } else if (pre != cur) { ok = 0; } } } ans += ok; return cnt; }; dfs(0, -1); return ans; } };
3,249
Count the Number of Good Nodes
Medium
<p>There is an <strong>undirected</strong> tree with <code>n</code> nodes labeled from <code>0</code> to <code>n - 1</code>, and rooted at node <code>0</code>. You are given a 2D integer array <code>edges</code> of length <code>n - 1</code>, where <code>edges[i] = [a<sub>i</sub>, b<sub>i</sub>]</code> indicates that there is an edge between nodes <code>a<sub>i</sub></code> and <code>b<sub>i</sub></code> in the tree.</p> <p>A node is <strong>good</strong> if all the <span data-keyword="subtree">subtrees</span> rooted at its children have the same size.</p> <p>Return the number of <strong>good</strong> nodes in the given tree.</p> <p>A <strong>subtree</strong> of <code>treeName</code> is a tree consisting of a node in <code>treeName</code> and all of its descendants.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">edges = [[0,1],[0,2],[1,3],[1,4],[2,5],[2,6]]</span></p> <p><strong>Output:</strong> <span class="example-io">7</span></p> <p><strong>Explanation:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3200-3299/3249.Count%20the%20Number%20of%20Good%20Nodes/images/tree1.png" style="width: 360px; height: 158px;" /> <p>All of the nodes of the given tree are good.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">edges = [[0,1],[1,2],[2,3],[3,4],[0,5],[1,6],[2,7],[3,8]]</span></p> <p><strong>Output:</strong> <span class="example-io">6</span></p> <p><strong>Explanation:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3200-3299/3249.Count%20the%20Number%20of%20Good%20Nodes/images/screenshot-2024-06-03-193552.png" style="width: 360px; height: 303px;" /> <p>There are 6 good nodes in the given tree. They are colored in the image above.</p> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">edges = [[0,1],[1,2],[1,3],[1,4],[0,5],[5,6],[6,7],[7,8],[0,9],[9,10],[9,12],[10,11]]</span></p> <p><strong>Output:</strong> <span class="example-io">12</span></p> <p><strong>Explanation:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3200-3299/3249.Count%20the%20Number%20of%20Good%20Nodes/images/rob.jpg" style="width: 450px; height: 277px;" /> <p>All nodes except node 9 are good.</p> </div> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= n &lt;= 10<sup>5</sup></code></li> <li><code>edges.length == n - 1</code></li> <li><code>edges[i].length == 2</code></li> <li><code>0 &lt;= a<sub>i</sub>, b<sub>i</sub> &lt; n</code></li> <li>The input is generated such that <code>edges</code> represents a valid tree.</li> </ul>
Tree; Depth-First Search
Go
func countGoodNodes(edges [][]int) (ans int) { n := len(edges) + 1 g := make([][]int, n) for _, e := range edges { a, b := e[0], e[1] g[a] = append(g[a], b) g[b] = append(g[b], a) } var dfs func(int, int) int dfs = func(a, fa int) int { pre, cnt, ok := -1, 1, 1 for _, b := range g[a] { if b != fa { cur := dfs(b, a) cnt += cur if pre < 0 { pre = cur } else if pre != cur { ok = 0 } } } ans += ok return cnt } dfs(0, -1) return }
3,249
Count the Number of Good Nodes
Medium
<p>There is an <strong>undirected</strong> tree with <code>n</code> nodes labeled from <code>0</code> to <code>n - 1</code>, and rooted at node <code>0</code>. You are given a 2D integer array <code>edges</code> of length <code>n - 1</code>, where <code>edges[i] = [a<sub>i</sub>, b<sub>i</sub>]</code> indicates that there is an edge between nodes <code>a<sub>i</sub></code> and <code>b<sub>i</sub></code> in the tree.</p> <p>A node is <strong>good</strong> if all the <span data-keyword="subtree">subtrees</span> rooted at its children have the same size.</p> <p>Return the number of <strong>good</strong> nodes in the given tree.</p> <p>A <strong>subtree</strong> of <code>treeName</code> is a tree consisting of a node in <code>treeName</code> and all of its descendants.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">edges = [[0,1],[0,2],[1,3],[1,4],[2,5],[2,6]]</span></p> <p><strong>Output:</strong> <span class="example-io">7</span></p> <p><strong>Explanation:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3200-3299/3249.Count%20the%20Number%20of%20Good%20Nodes/images/tree1.png" style="width: 360px; height: 158px;" /> <p>All of the nodes of the given tree are good.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">edges = [[0,1],[1,2],[2,3],[3,4],[0,5],[1,6],[2,7],[3,8]]</span></p> <p><strong>Output:</strong> <span class="example-io">6</span></p> <p><strong>Explanation:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3200-3299/3249.Count%20the%20Number%20of%20Good%20Nodes/images/screenshot-2024-06-03-193552.png" style="width: 360px; height: 303px;" /> <p>There are 6 good nodes in the given tree. They are colored in the image above.</p> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">edges = [[0,1],[1,2],[1,3],[1,4],[0,5],[5,6],[6,7],[7,8],[0,9],[9,10],[9,12],[10,11]]</span></p> <p><strong>Output:</strong> <span class="example-io">12</span></p> <p><strong>Explanation:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3200-3299/3249.Count%20the%20Number%20of%20Good%20Nodes/images/rob.jpg" style="width: 450px; height: 277px;" /> <p>All nodes except node 9 are good.</p> </div> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= n &lt;= 10<sup>5</sup></code></li> <li><code>edges.length == n - 1</code></li> <li><code>edges[i].length == 2</code></li> <li><code>0 &lt;= a<sub>i</sub>, b<sub>i</sub> &lt; n</code></li> <li>The input is generated such that <code>edges</code> represents a valid tree.</li> </ul>
Tree; Depth-First Search
Java
class Solution { private int ans; private List<Integer>[] g; public int countGoodNodes(int[][] edges) { int n = edges.length + 1; g = new List[n]; Arrays.setAll(g, k -> new ArrayList<>()); for (var e : edges) { int a = e[0], b = e[1]; g[a].add(b); g[b].add(a); } dfs(0, -1); return ans; } private int dfs(int a, int fa) { int pre = -1, cnt = 1, ok = 1; for (int b : g[a]) { if (b != fa) { int cur = dfs(b, a); cnt += cur; if (pre < 0) { pre = cur; } else if (pre != cur) { ok = 0; } } } ans += ok; return cnt; } }
3,249
Count the Number of Good Nodes
Medium
<p>There is an <strong>undirected</strong> tree with <code>n</code> nodes labeled from <code>0</code> to <code>n - 1</code>, and rooted at node <code>0</code>. You are given a 2D integer array <code>edges</code> of length <code>n - 1</code>, where <code>edges[i] = [a<sub>i</sub>, b<sub>i</sub>]</code> indicates that there is an edge between nodes <code>a<sub>i</sub></code> and <code>b<sub>i</sub></code> in the tree.</p> <p>A node is <strong>good</strong> if all the <span data-keyword="subtree">subtrees</span> rooted at its children have the same size.</p> <p>Return the number of <strong>good</strong> nodes in the given tree.</p> <p>A <strong>subtree</strong> of <code>treeName</code> is a tree consisting of a node in <code>treeName</code> and all of its descendants.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">edges = [[0,1],[0,2],[1,3],[1,4],[2,5],[2,6]]</span></p> <p><strong>Output:</strong> <span class="example-io">7</span></p> <p><strong>Explanation:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3200-3299/3249.Count%20the%20Number%20of%20Good%20Nodes/images/tree1.png" style="width: 360px; height: 158px;" /> <p>All of the nodes of the given tree are good.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">edges = [[0,1],[1,2],[2,3],[3,4],[0,5],[1,6],[2,7],[3,8]]</span></p> <p><strong>Output:</strong> <span class="example-io">6</span></p> <p><strong>Explanation:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3200-3299/3249.Count%20the%20Number%20of%20Good%20Nodes/images/screenshot-2024-06-03-193552.png" style="width: 360px; height: 303px;" /> <p>There are 6 good nodes in the given tree. They are colored in the image above.</p> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">edges = [[0,1],[1,2],[1,3],[1,4],[0,5],[5,6],[6,7],[7,8],[0,9],[9,10],[9,12],[10,11]]</span></p> <p><strong>Output:</strong> <span class="example-io">12</span></p> <p><strong>Explanation:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3200-3299/3249.Count%20the%20Number%20of%20Good%20Nodes/images/rob.jpg" style="width: 450px; height: 277px;" /> <p>All nodes except node 9 are good.</p> </div> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= n &lt;= 10<sup>5</sup></code></li> <li><code>edges.length == n - 1</code></li> <li><code>edges[i].length == 2</code></li> <li><code>0 &lt;= a<sub>i</sub>, b<sub>i</sub> &lt; n</code></li> <li>The input is generated such that <code>edges</code> represents a valid tree.</li> </ul>
Tree; Depth-First Search
Python
class Solution: def countGoodNodes(self, edges: List[List[int]]) -> int: def dfs(a: int, fa: int) -> int: pre = -1 cnt = ok = 1 for b in g[a]: if b != fa: cur = dfs(b, a) cnt += cur if pre < 0: pre = cur elif pre != cur: ok = 0 nonlocal ans ans += ok return cnt g = defaultdict(list) for a, b in edges: g[a].append(b) g[b].append(a) ans = 0 dfs(0, -1) return ans
3,249
Count the Number of Good Nodes
Medium
<p>There is an <strong>undirected</strong> tree with <code>n</code> nodes labeled from <code>0</code> to <code>n - 1</code>, and rooted at node <code>0</code>. You are given a 2D integer array <code>edges</code> of length <code>n - 1</code>, where <code>edges[i] = [a<sub>i</sub>, b<sub>i</sub>]</code> indicates that there is an edge between nodes <code>a<sub>i</sub></code> and <code>b<sub>i</sub></code> in the tree.</p> <p>A node is <strong>good</strong> if all the <span data-keyword="subtree">subtrees</span> rooted at its children have the same size.</p> <p>Return the number of <strong>good</strong> nodes in the given tree.</p> <p>A <strong>subtree</strong> of <code>treeName</code> is a tree consisting of a node in <code>treeName</code> and all of its descendants.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">edges = [[0,1],[0,2],[1,3],[1,4],[2,5],[2,6]]</span></p> <p><strong>Output:</strong> <span class="example-io">7</span></p> <p><strong>Explanation:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3200-3299/3249.Count%20the%20Number%20of%20Good%20Nodes/images/tree1.png" style="width: 360px; height: 158px;" /> <p>All of the nodes of the given tree are good.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">edges = [[0,1],[1,2],[2,3],[3,4],[0,5],[1,6],[2,7],[3,8]]</span></p> <p><strong>Output:</strong> <span class="example-io">6</span></p> <p><strong>Explanation:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3200-3299/3249.Count%20the%20Number%20of%20Good%20Nodes/images/screenshot-2024-06-03-193552.png" style="width: 360px; height: 303px;" /> <p>There are 6 good nodes in the given tree. They are colored in the image above.</p> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">edges = [[0,1],[1,2],[1,3],[1,4],[0,5],[5,6],[6,7],[7,8],[0,9],[9,10],[9,12],[10,11]]</span></p> <p><strong>Output:</strong> <span class="example-io">12</span></p> <p><strong>Explanation:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3200-3299/3249.Count%20the%20Number%20of%20Good%20Nodes/images/rob.jpg" style="width: 450px; height: 277px;" /> <p>All nodes except node 9 are good.</p> </div> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= n &lt;= 10<sup>5</sup></code></li> <li><code>edges.length == n - 1</code></li> <li><code>edges[i].length == 2</code></li> <li><code>0 &lt;= a<sub>i</sub>, b<sub>i</sub> &lt; n</code></li> <li>The input is generated such that <code>edges</code> represents a valid tree.</li> </ul>
Tree; Depth-First Search
TypeScript
function countGoodNodes(edges: number[][]): number { const n = edges.length + 1; const g: number[][] = Array.from({ length: n }, () => []); for (const [a, b] of edges) { g[a].push(b); g[b].push(a); } let ans = 0; const dfs = (a: number, fa: number): number => { let [pre, cnt, ok] = [-1, 1, 1]; for (const b of g[a]) { if (b !== fa) { const cur = dfs(b, a); cnt += cur; if (pre < 0) { pre = cur; } else if (pre !== cur) { ok = 0; } } } ans += ok; return cnt; }; dfs(0, -1); return ans; }
3,250
Find the Count of Monotonic Pairs I
Hard
<p>You are given an array of <strong>positive</strong> integers <code>nums</code> of length <code>n</code>.</p> <p>We call a pair of <strong>non-negative</strong> integer arrays <code>(arr1, arr2)</code> <strong>monotonic</strong> if:</p> <ul> <li>The lengths of both arrays are <code>n</code>.</li> <li><code>arr1</code> is monotonically <strong>non-decreasing</strong>, in other words, <code>arr1[0] &lt;= arr1[1] &lt;= ... &lt;= arr1[n - 1]</code>.</li> <li><code>arr2</code> is monotonically <strong>non-increasing</strong>, in other words, <code>arr2[0] &gt;= arr2[1] &gt;= ... &gt;= arr2[n - 1]</code>.</li> <li><code>arr1[i] + arr2[i] == nums[i]</code> for all <code>0 &lt;= i &lt;= n - 1</code>.</li> </ul> <p>Return the count of <strong>monotonic</strong> pairs.</p> <p>Since the answer may be very large, return it <strong>modulo</strong> <code>10<sup>9</sup> + 7</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,3,2]</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <p>The good pairs are:</p> <ol> <li><code>([0, 1, 1], [2, 2, 1])</code></li> <li><code>([0, 1, 2], [2, 2, 0])</code></li> <li><code>([0, 2, 2], [2, 1, 0])</code></li> <li><code>([1, 2, 2], [1, 1, 0])</code></li> </ol> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [5,5,5,5]</span></p> <p><strong>Output:</strong> <span class="example-io">126</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == nums.length &lt;= 2000</code></li> <li><code>1 &lt;= nums[i] &lt;= 50</code></li> </ul>
Array; Math; Dynamic Programming; Combinatorics; Prefix Sum
C++
class Solution { public: int countOfPairs(vector<int>& nums) { const int mod = 1e9 + 7; int n = nums.size(); int m = *max_element(nums.begin(), nums.end()); vector<vector<int>> f(n, vector<int>(m + 1)); for (int j = 0; j <= nums[0]; ++j) { f[0][j] = 1; } vector<int> g(m + 1); for (int i = 1; i < n; ++i) { g[0] = f[i - 1][0]; for (int j = 1; j <= m; ++j) { g[j] = (g[j - 1] + f[i - 1][j]) % mod; } for (int j = 0; j <= nums[i]; ++j) { int k = min(j, j + nums[i - 1] - nums[i]); if (k >= 0) { f[i][j] = g[k]; } } } int ans = 0; for (int j = 0; j <= nums[n - 1]; ++j) { ans = (ans + f[n - 1][j]) % mod; } return ans; } };
3,250
Find the Count of Monotonic Pairs I
Hard
<p>You are given an array of <strong>positive</strong> integers <code>nums</code> of length <code>n</code>.</p> <p>We call a pair of <strong>non-negative</strong> integer arrays <code>(arr1, arr2)</code> <strong>monotonic</strong> if:</p> <ul> <li>The lengths of both arrays are <code>n</code>.</li> <li><code>arr1</code> is monotonically <strong>non-decreasing</strong>, in other words, <code>arr1[0] &lt;= arr1[1] &lt;= ... &lt;= arr1[n - 1]</code>.</li> <li><code>arr2</code> is monotonically <strong>non-increasing</strong>, in other words, <code>arr2[0] &gt;= arr2[1] &gt;= ... &gt;= arr2[n - 1]</code>.</li> <li><code>arr1[i] + arr2[i] == nums[i]</code> for all <code>0 &lt;= i &lt;= n - 1</code>.</li> </ul> <p>Return the count of <strong>monotonic</strong> pairs.</p> <p>Since the answer may be very large, return it <strong>modulo</strong> <code>10<sup>9</sup> + 7</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,3,2]</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <p>The good pairs are:</p> <ol> <li><code>([0, 1, 1], [2, 2, 1])</code></li> <li><code>([0, 1, 2], [2, 2, 0])</code></li> <li><code>([0, 2, 2], [2, 1, 0])</code></li> <li><code>([1, 2, 2], [1, 1, 0])</code></li> </ol> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [5,5,5,5]</span></p> <p><strong>Output:</strong> <span class="example-io">126</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == nums.length &lt;= 2000</code></li> <li><code>1 &lt;= nums[i] &lt;= 50</code></li> </ul>
Array; Math; Dynamic Programming; Combinatorics; Prefix Sum
Go
func countOfPairs(nums []int) (ans int) { const mod int = 1e9 + 7 n := len(nums) m := slices.Max(nums) f := make([][]int, n) for i := range f { f[i] = make([]int, m+1) } for j := 0; j <= nums[0]; j++ { f[0][j] = 1 } g := make([]int, m+1) for i := 1; i < n; i++ { g[0] = f[i-1][0] for j := 1; j <= m; j++ { g[j] = (g[j-1] + f[i-1][j]) % mod } for j := 0; j <= nums[i]; j++ { k := min(j, j+nums[i-1]-nums[i]) if k >= 0 { f[i][j] = g[k] } } } for j := 0; j <= nums[n-1]; j++ { ans = (ans + f[n-1][j]) % mod } return }
3,250
Find the Count of Monotonic Pairs I
Hard
<p>You are given an array of <strong>positive</strong> integers <code>nums</code> of length <code>n</code>.</p> <p>We call a pair of <strong>non-negative</strong> integer arrays <code>(arr1, arr2)</code> <strong>monotonic</strong> if:</p> <ul> <li>The lengths of both arrays are <code>n</code>.</li> <li><code>arr1</code> is monotonically <strong>non-decreasing</strong>, in other words, <code>arr1[0] &lt;= arr1[1] &lt;= ... &lt;= arr1[n - 1]</code>.</li> <li><code>arr2</code> is monotonically <strong>non-increasing</strong>, in other words, <code>arr2[0] &gt;= arr2[1] &gt;= ... &gt;= arr2[n - 1]</code>.</li> <li><code>arr1[i] + arr2[i] == nums[i]</code> for all <code>0 &lt;= i &lt;= n - 1</code>.</li> </ul> <p>Return the count of <strong>monotonic</strong> pairs.</p> <p>Since the answer may be very large, return it <strong>modulo</strong> <code>10<sup>9</sup> + 7</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,3,2]</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <p>The good pairs are:</p> <ol> <li><code>([0, 1, 1], [2, 2, 1])</code></li> <li><code>([0, 1, 2], [2, 2, 0])</code></li> <li><code>([0, 2, 2], [2, 1, 0])</code></li> <li><code>([1, 2, 2], [1, 1, 0])</code></li> </ol> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [5,5,5,5]</span></p> <p><strong>Output:</strong> <span class="example-io">126</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == nums.length &lt;= 2000</code></li> <li><code>1 &lt;= nums[i] &lt;= 50</code></li> </ul>
Array; Math; Dynamic Programming; Combinatorics; Prefix Sum
Java
class Solution { public int countOfPairs(int[] nums) { final int mod = (int) 1e9 + 7; int n = nums.length; int m = Arrays.stream(nums).max().getAsInt(); int[][] f = new int[n][m + 1]; for (int j = 0; j <= nums[0]; ++j) { f[0][j] = 1; } int[] g = new int[m + 1]; for (int i = 1; i < n; ++i) { g[0] = f[i - 1][0]; for (int j = 1; j <= m; ++j) { g[j] = (g[j - 1] + f[i - 1][j]) % mod; } for (int j = 0; j <= nums[i]; ++j) { int k = Math.min(j, j + nums[i - 1] - nums[i]); if (k >= 0) { f[i][j] = g[k]; } } } int ans = 0; for (int j = 0; j <= nums[n - 1]; ++j) { ans = (ans + f[n - 1][j]) % mod; } return ans; } }
3,250
Find the Count of Monotonic Pairs I
Hard
<p>You are given an array of <strong>positive</strong> integers <code>nums</code> of length <code>n</code>.</p> <p>We call a pair of <strong>non-negative</strong> integer arrays <code>(arr1, arr2)</code> <strong>monotonic</strong> if:</p> <ul> <li>The lengths of both arrays are <code>n</code>.</li> <li><code>arr1</code> is monotonically <strong>non-decreasing</strong>, in other words, <code>arr1[0] &lt;= arr1[1] &lt;= ... &lt;= arr1[n - 1]</code>.</li> <li><code>arr2</code> is monotonically <strong>non-increasing</strong>, in other words, <code>arr2[0] &gt;= arr2[1] &gt;= ... &gt;= arr2[n - 1]</code>.</li> <li><code>arr1[i] + arr2[i] == nums[i]</code> for all <code>0 &lt;= i &lt;= n - 1</code>.</li> </ul> <p>Return the count of <strong>monotonic</strong> pairs.</p> <p>Since the answer may be very large, return it <strong>modulo</strong> <code>10<sup>9</sup> + 7</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,3,2]</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <p>The good pairs are:</p> <ol> <li><code>([0, 1, 1], [2, 2, 1])</code></li> <li><code>([0, 1, 2], [2, 2, 0])</code></li> <li><code>([0, 2, 2], [2, 1, 0])</code></li> <li><code>([1, 2, 2], [1, 1, 0])</code></li> </ol> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [5,5,5,5]</span></p> <p><strong>Output:</strong> <span class="example-io">126</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == nums.length &lt;= 2000</code></li> <li><code>1 &lt;= nums[i] &lt;= 50</code></li> </ul>
Array; Math; Dynamic Programming; Combinatorics; Prefix Sum
Python
class Solution: def countOfPairs(self, nums: List[int]) -> int: mod = 10**9 + 7 n, m = len(nums), max(nums) f = [[0] * (m + 1) for _ in range(n)] for j in range(nums[0] + 1): f[0][j] = 1 for i in range(1, n): s = list(accumulate(f[i - 1])) for j in range(nums[i] + 1): k = min(j, j + nums[i - 1] - nums[i]) if k >= 0: f[i][j] = s[k] % mod return sum(f[-1][: nums[-1] + 1]) % mod
3,250
Find the Count of Monotonic Pairs I
Hard
<p>You are given an array of <strong>positive</strong> integers <code>nums</code> of length <code>n</code>.</p> <p>We call a pair of <strong>non-negative</strong> integer arrays <code>(arr1, arr2)</code> <strong>monotonic</strong> if:</p> <ul> <li>The lengths of both arrays are <code>n</code>.</li> <li><code>arr1</code> is monotonically <strong>non-decreasing</strong>, in other words, <code>arr1[0] &lt;= arr1[1] &lt;= ... &lt;= arr1[n - 1]</code>.</li> <li><code>arr2</code> is monotonically <strong>non-increasing</strong>, in other words, <code>arr2[0] &gt;= arr2[1] &gt;= ... &gt;= arr2[n - 1]</code>.</li> <li><code>arr1[i] + arr2[i] == nums[i]</code> for all <code>0 &lt;= i &lt;= n - 1</code>.</li> </ul> <p>Return the count of <strong>monotonic</strong> pairs.</p> <p>Since the answer may be very large, return it <strong>modulo</strong> <code>10<sup>9</sup> + 7</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,3,2]</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <p>The good pairs are:</p> <ol> <li><code>([0, 1, 1], [2, 2, 1])</code></li> <li><code>([0, 1, 2], [2, 2, 0])</code></li> <li><code>([0, 2, 2], [2, 1, 0])</code></li> <li><code>([1, 2, 2], [1, 1, 0])</code></li> </ol> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [5,5,5,5]</span></p> <p><strong>Output:</strong> <span class="example-io">126</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == nums.length &lt;= 2000</code></li> <li><code>1 &lt;= nums[i] &lt;= 50</code></li> </ul>
Array; Math; Dynamic Programming; Combinatorics; Prefix Sum
TypeScript
function countOfPairs(nums: number[]): number { const mod = 1e9 + 7; const n = nums.length; const m = Math.max(...nums); const f: number[][] = Array.from({ length: n }, () => Array(m + 1).fill(0)); for (let j = 0; j <= nums[0]; j++) { f[0][j] = 1; } const g: number[] = Array(m + 1).fill(0); for (let i = 1; i < n; i++) { g[0] = f[i - 1][0]; for (let j = 1; j <= m; j++) { g[j] = (g[j - 1] + f[i - 1][j]) % mod; } for (let j = 0; j <= nums[i]; j++) { const k = Math.min(j, j + nums[i - 1] - nums[i]); if (k >= 0) { f[i][j] = g[k]; } } } let ans = 0; for (let j = 0; j <= nums[n - 1]; j++) { ans = (ans + f[n - 1][j]) % mod; } return ans; }
3,251
Find the Count of Monotonic Pairs II
Hard
<p>You are given an array of <strong>positive</strong> integers <code>nums</code> of length <code>n</code>.</p> <p>We call a pair of <strong>non-negative</strong> integer arrays <code>(arr1, arr2)</code> <strong>monotonic</strong> if:</p> <ul> <li>The lengths of both arrays are <code>n</code>.</li> <li><code>arr1</code> is monotonically <strong>non-decreasing</strong>, in other words, <code>arr1[0] &lt;= arr1[1] &lt;= ... &lt;= arr1[n - 1]</code>.</li> <li><code>arr2</code> is monotonically <strong>non-increasing</strong>, in other words, <code>arr2[0] &gt;= arr2[1] &gt;= ... &gt;= arr2[n - 1]</code>.</li> <li><code>arr1[i] + arr2[i] == nums[i]</code> for all <code>0 &lt;= i &lt;= n - 1</code>.</li> </ul> <p>Return the count of <strong>monotonic</strong> pairs.</p> <p>Since the answer may be very large, return it <strong>modulo</strong> <code>10<sup>9</sup> + 7</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,3,2]</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <p>The good pairs are:</p> <ol> <li><code>([0, 1, 1], [2, 2, 1])</code></li> <li><code>([0, 1, 2], [2, 2, 0])</code></li> <li><code>([0, 2, 2], [2, 1, 0])</code></li> <li><code>([1, 2, 2], [1, 1, 0])</code></li> </ol> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [5,5,5,5]</span></p> <p><strong>Output:</strong> <span class="example-io">126</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == nums.length &lt;= 2000</code></li> <li><code>1 &lt;= nums[i] &lt;= 1000</code></li> </ul>
Array; Math; Dynamic Programming; Combinatorics; Prefix Sum
C++
class Solution { public: int countOfPairs(vector<int>& nums) { const int mod = 1e9 + 7; int n = nums.size(); int m = *max_element(nums.begin(), nums.end()); vector<vector<int>> f(n, vector<int>(m + 1)); for (int j = 0; j <= nums[0]; ++j) { f[0][j] = 1; } vector<int> g(m + 1); for (int i = 1; i < n; ++i) { g[0] = f[i - 1][0]; for (int j = 1; j <= m; ++j) { g[j] = (g[j - 1] + f[i - 1][j]) % mod; } for (int j = 0; j <= nums[i]; ++j) { int k = min(j, j + nums[i - 1] - nums[i]); if (k >= 0) { f[i][j] = g[k]; } } } int ans = 0; for (int j = 0; j <= nums[n - 1]; ++j) { ans = (ans + f[n - 1][j]) % mod; } return ans; } };
3,251
Find the Count of Monotonic Pairs II
Hard
<p>You are given an array of <strong>positive</strong> integers <code>nums</code> of length <code>n</code>.</p> <p>We call a pair of <strong>non-negative</strong> integer arrays <code>(arr1, arr2)</code> <strong>monotonic</strong> if:</p> <ul> <li>The lengths of both arrays are <code>n</code>.</li> <li><code>arr1</code> is monotonically <strong>non-decreasing</strong>, in other words, <code>arr1[0] &lt;= arr1[1] &lt;= ... &lt;= arr1[n - 1]</code>.</li> <li><code>arr2</code> is monotonically <strong>non-increasing</strong>, in other words, <code>arr2[0] &gt;= arr2[1] &gt;= ... &gt;= arr2[n - 1]</code>.</li> <li><code>arr1[i] + arr2[i] == nums[i]</code> for all <code>0 &lt;= i &lt;= n - 1</code>.</li> </ul> <p>Return the count of <strong>monotonic</strong> pairs.</p> <p>Since the answer may be very large, return it <strong>modulo</strong> <code>10<sup>9</sup> + 7</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,3,2]</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <p>The good pairs are:</p> <ol> <li><code>([0, 1, 1], [2, 2, 1])</code></li> <li><code>([0, 1, 2], [2, 2, 0])</code></li> <li><code>([0, 2, 2], [2, 1, 0])</code></li> <li><code>([1, 2, 2], [1, 1, 0])</code></li> </ol> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [5,5,5,5]</span></p> <p><strong>Output:</strong> <span class="example-io">126</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == nums.length &lt;= 2000</code></li> <li><code>1 &lt;= nums[i] &lt;= 1000</code></li> </ul>
Array; Math; Dynamic Programming; Combinatorics; Prefix Sum
Go
func countOfPairs(nums []int) (ans int) { const mod int = 1e9 + 7 n := len(nums) m := slices.Max(nums) f := make([][]int, n) for i := range f { f[i] = make([]int, m+1) } for j := 0; j <= nums[0]; j++ { f[0][j] = 1 } g := make([]int, m+1) for i := 1; i < n; i++ { g[0] = f[i-1][0] for j := 1; j <= m; j++ { g[j] = (g[j-1] + f[i-1][j]) % mod } for j := 0; j <= nums[i]; j++ { k := min(j, j+nums[i-1]-nums[i]) if k >= 0 { f[i][j] = g[k] } } } for j := 0; j <= nums[n-1]; j++ { ans = (ans + f[n-1][j]) % mod } return }
3,251
Find the Count of Monotonic Pairs II
Hard
<p>You are given an array of <strong>positive</strong> integers <code>nums</code> of length <code>n</code>.</p> <p>We call a pair of <strong>non-negative</strong> integer arrays <code>(arr1, arr2)</code> <strong>monotonic</strong> if:</p> <ul> <li>The lengths of both arrays are <code>n</code>.</li> <li><code>arr1</code> is monotonically <strong>non-decreasing</strong>, in other words, <code>arr1[0] &lt;= arr1[1] &lt;= ... &lt;= arr1[n - 1]</code>.</li> <li><code>arr2</code> is monotonically <strong>non-increasing</strong>, in other words, <code>arr2[0] &gt;= arr2[1] &gt;= ... &gt;= arr2[n - 1]</code>.</li> <li><code>arr1[i] + arr2[i] == nums[i]</code> for all <code>0 &lt;= i &lt;= n - 1</code>.</li> </ul> <p>Return the count of <strong>monotonic</strong> pairs.</p> <p>Since the answer may be very large, return it <strong>modulo</strong> <code>10<sup>9</sup> + 7</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,3,2]</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <p>The good pairs are:</p> <ol> <li><code>([0, 1, 1], [2, 2, 1])</code></li> <li><code>([0, 1, 2], [2, 2, 0])</code></li> <li><code>([0, 2, 2], [2, 1, 0])</code></li> <li><code>([1, 2, 2], [1, 1, 0])</code></li> </ol> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [5,5,5,5]</span></p> <p><strong>Output:</strong> <span class="example-io">126</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == nums.length &lt;= 2000</code></li> <li><code>1 &lt;= nums[i] &lt;= 1000</code></li> </ul>
Array; Math; Dynamic Programming; Combinatorics; Prefix Sum
Java
class Solution { public int countOfPairs(int[] nums) { final int mod = (int) 1e9 + 7; int n = nums.length; int m = Arrays.stream(nums).max().getAsInt(); int[][] f = new int[n][m + 1]; for (int j = 0; j <= nums[0]; ++j) { f[0][j] = 1; } int[] g = new int[m + 1]; for (int i = 1; i < n; ++i) { g[0] = f[i - 1][0]; for (int j = 1; j <= m; ++j) { g[j] = (g[j - 1] + f[i - 1][j]) % mod; } for (int j = 0; j <= nums[i]; ++j) { int k = Math.min(j, j + nums[i - 1] - nums[i]); if (k >= 0) { f[i][j] = g[k]; } } } int ans = 0; for (int j = 0; j <= nums[n - 1]; ++j) { ans = (ans + f[n - 1][j]) % mod; } return ans; } }
3,251
Find the Count of Monotonic Pairs II
Hard
<p>You are given an array of <strong>positive</strong> integers <code>nums</code> of length <code>n</code>.</p> <p>We call a pair of <strong>non-negative</strong> integer arrays <code>(arr1, arr2)</code> <strong>monotonic</strong> if:</p> <ul> <li>The lengths of both arrays are <code>n</code>.</li> <li><code>arr1</code> is monotonically <strong>non-decreasing</strong>, in other words, <code>arr1[0] &lt;= arr1[1] &lt;= ... &lt;= arr1[n - 1]</code>.</li> <li><code>arr2</code> is monotonically <strong>non-increasing</strong>, in other words, <code>arr2[0] &gt;= arr2[1] &gt;= ... &gt;= arr2[n - 1]</code>.</li> <li><code>arr1[i] + arr2[i] == nums[i]</code> for all <code>0 &lt;= i &lt;= n - 1</code>.</li> </ul> <p>Return the count of <strong>monotonic</strong> pairs.</p> <p>Since the answer may be very large, return it <strong>modulo</strong> <code>10<sup>9</sup> + 7</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,3,2]</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <p>The good pairs are:</p> <ol> <li><code>([0, 1, 1], [2, 2, 1])</code></li> <li><code>([0, 1, 2], [2, 2, 0])</code></li> <li><code>([0, 2, 2], [2, 1, 0])</code></li> <li><code>([1, 2, 2], [1, 1, 0])</code></li> </ol> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [5,5,5,5]</span></p> <p><strong>Output:</strong> <span class="example-io">126</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == nums.length &lt;= 2000</code></li> <li><code>1 &lt;= nums[i] &lt;= 1000</code></li> </ul>
Array; Math; Dynamic Programming; Combinatorics; Prefix Sum
Python
class Solution: def countOfPairs(self, nums: List[int]) -> int: mod = 10**9 + 7 n, m = len(nums), max(nums) f = [[0] * (m + 1) for _ in range(n)] for j in range(nums[0] + 1): f[0][j] = 1 for i in range(1, n): s = list(accumulate(f[i - 1])) for j in range(nums[i] + 1): k = min(j, j + nums[i - 1] - nums[i]) if k >= 0: f[i][j] = s[k] % mod return sum(f[-1][: nums[-1] + 1]) % mod
3,251
Find the Count of Monotonic Pairs II
Hard
<p>You are given an array of <strong>positive</strong> integers <code>nums</code> of length <code>n</code>.</p> <p>We call a pair of <strong>non-negative</strong> integer arrays <code>(arr1, arr2)</code> <strong>monotonic</strong> if:</p> <ul> <li>The lengths of both arrays are <code>n</code>.</li> <li><code>arr1</code> is monotonically <strong>non-decreasing</strong>, in other words, <code>arr1[0] &lt;= arr1[1] &lt;= ... &lt;= arr1[n - 1]</code>.</li> <li><code>arr2</code> is monotonically <strong>non-increasing</strong>, in other words, <code>arr2[0] &gt;= arr2[1] &gt;= ... &gt;= arr2[n - 1]</code>.</li> <li><code>arr1[i] + arr2[i] == nums[i]</code> for all <code>0 &lt;= i &lt;= n - 1</code>.</li> </ul> <p>Return the count of <strong>monotonic</strong> pairs.</p> <p>Since the answer may be very large, return it <strong>modulo</strong> <code>10<sup>9</sup> + 7</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,3,2]</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <p>The good pairs are:</p> <ol> <li><code>([0, 1, 1], [2, 2, 1])</code></li> <li><code>([0, 1, 2], [2, 2, 0])</code></li> <li><code>([0, 2, 2], [2, 1, 0])</code></li> <li><code>([1, 2, 2], [1, 1, 0])</code></li> </ol> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [5,5,5,5]</span></p> <p><strong>Output:</strong> <span class="example-io">126</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == nums.length &lt;= 2000</code></li> <li><code>1 &lt;= nums[i] &lt;= 1000</code></li> </ul>
Array; Math; Dynamic Programming; Combinatorics; Prefix Sum
TypeScript
function countOfPairs(nums: number[]): number { const mod = 1e9 + 7; const n = nums.length; const m = Math.max(...nums); const f: number[][] = Array.from({ length: n }, () => Array(m + 1).fill(0)); for (let j = 0; j <= nums[0]; j++) { f[0][j] = 1; } const g: number[] = Array(m + 1).fill(0); for (let i = 1; i < n; i++) { g[0] = f[i - 1][0]; for (let j = 1; j <= m; j++) { g[j] = (g[j - 1] + f[i - 1][j]) % mod; } for (let j = 0; j <= nums[i]; j++) { const k = Math.min(j, j + nums[i - 1] - nums[i]); if (k >= 0) { f[i][j] = g[k]; } } } let ans = 0; for (let j = 0; j <= nums[n - 1]; j++) { ans = (ans + f[n - 1][j]) % mod; } return ans; }
3,252
Premier League Table Ranking II
Medium
<p>Table: <code>TeamStats</code></p> <pre> +------------------+---------+ | Column Name | Type | +------------------+---------+ | team_id | int | | team_name | varchar | | matches_played | int | | wins | int | | draws | int | | losses | int | +------------------+---------+ team_id is the unique key for this table. This table contains team id, team name, matches_played, wins, draws, and losses. </pre> <p>Write a solution to calculate the <strong>points</strong>, <strong>position</strong>, and <strong>tier</strong> for each team in the league. Points are calculated as follows:</p> <ul> <li><code>3</code> points for a <strong>win</strong></li> <li><code>1</code> point for a <strong>draw</strong></li> <li><code>0</code> points for a <strong>loss</strong></li> </ul> <p><strong>Note:</strong>&nbsp;Teams with the same points must be assigned the same position.</p> <p><strong>Tier ranking:</strong></p> <ul> <li>Divide the league into <code>3</code> tiers based on points:</li> <li>Tier 1: Top <code>33%</code> of teams</li> <li>Tier 2: Middle <code>33%</code> of teams</li> <li>Tier 3: Bottom<code> 34%</code> of teams</li> <li>In case of <strong>ties</strong> at<strong> tier boundaries</strong>, place tied teams in the <strong>higher tier</strong>.</li> </ul> <p>Return <em>the result table </em><em>ordered by</em> <code>points</code>&nbsp;<em>in&nbsp;<strong>descending</strong>,<strong>&nbsp;</strong>and then by</em> <code>team_name</code> <em>in <strong>ascending</strong> order.</em></p> <p>The query result format is in the following example.</p> <p>&nbsp;</p> <p><strong class="example">Example:</strong></p> <div class="example-block"> <p><strong>Input:</strong></p> <p><code>TeamStats</code> table:</p> <pre class="example-io"> +---------+-------------------+----------------+------+-------+--------+ | team_id | team_name | matches_played | wins | draws | losses | +---------+-------------------+----------------+------+-------+--------+ | 1 | Chelsea | 22 | 13 | 2 | 7 | | 2 | Nottingham Forest | 27 | 6 | 6 | 15 | | 3 | Liverpool | 17 | 1 | 8 | 8 | | 4 | Aston Villa | 20 | 1 | 6 | 13 | | 5 | Fulham | 31 | 18 | 1 | 12 | | 6 | Burnley | 26 | 6 | 9 | 11 | | 7 | Newcastle United | 33 | 11 | 10 | 12 | | 8 | Sheffield United | 20 | 18 | 2 | 0 | | 9 | Luton Town | 5 | 4 | 0 | 1 | | 10 | Everton | 14 | 2 | 6 | 6 | +---------+-------------------+----------------+------+-------+--------+ </pre> <p><strong>Output:</strong></p> <pre class="example-io"> +-------------------+--------+----------+---------+ | team_name | points | position | tier | +-------------------+--------+----------+---------+ | Sheffield United | 56 | 1 | Tier 1 | | Fulham | 55 | 2 | Tier 1 | | Newcastle United | 43 | 3 | Tier 1 | | Chelsea | 41 | 4 | Tier 1 | | Burnley | 27 | 5 | Tier 2 | | Nottingham Forest | 24 | 6 | Tier 2 | | Everton | 12 | 7 | Tier 2 | | Luton Town | 12 | 7 | Tier 2 | | Liverpool | 11 | 9 | Tier 3 | | Aston Villa | 9 | 10 | Tier 3 | +-------------------+--------+----------+---------+ </pre> <p><strong>Explanation:</strong></p> <ul> <li>Sheffield United has 56 points (18 wins * 3 points + 2 draws * 1 point) and is in position 1.</li> <li>Fulham has 55 points (18 wins * 3 points + 1 draw * 1 point) and is in position 2.</li> <li>Newcastle United has 43 points (11 wins * 3 points + 10 draws * 1 point) and is in position 3.</li> <li>Chelsea has 41 points (13 wins * 3 points + 2 draws * 1 point) and is in position 4.</li> <li>Burnley has 27 points (6 wins * 3 points + 9 draws * 1 point) and is in position 5.</li> <li>Nottingham Forest has 24 points (6 wins * 3 points + 6 draws * 1 point) and is in position 6.</li> <li>Everton and Luton Town both have 12 points, with Everton having 2 wins * 3 points + 6 draws * 1 point, and Luton Town having 4 wins * 3 points. Both teams share position 7.</li> <li>Liverpool has 11 points (1 win * 3 points + 8 draws * 1 point) and is in position 9.</li> <li>Aston Villa has 9 points (1 win * 3 points + 6 draws * 1 point) and is in position 10.</li> </ul> <p><strong>Tier Calculation:</strong></p> <ul> <li><strong>Tier 1:</strong> The top 33% of teams based on points. Sheffield United, Fulham, Newcastle United, and Chelsea fall into Tier 1.</li> <li><strong>Tier 2:</strong> The middle 33% of teams. Burnley, Nottingham Forest, Everton, and Luton Town fall into Tier 2.</li> <li><strong>Tier 3:</strong> The bottom 34% of teams. Liverpool and Aston Villa fall into Tier 3.</li> </ul> </div>
Database
Python
import pandas as pd def calculate_team_tiers(team_stats: pd.DataFrame) -> pd.DataFrame: team_stats["points"] = team_stats["wins"] * 3 + team_stats["draws"] team_stats["position"] = ( team_stats["points"].rank(method="min", ascending=False).astype(int) ) total_teams = len(team_stats) team_stats["tier"] = np.where( team_stats["position"] <= np.ceil(total_teams / 3.0), "Tier 1", np.where( team_stats["position"] <= np.ceil(2 * total_teams / 3.0), "Tier 2", "Tier 3" ), ) team_stats = team_stats.sort_values( by=["points", "team_name"], ascending=[False, True] ) return team_stats[["team_name", "points", "position", "tier"]]
3,252
Premier League Table Ranking II
Medium
<p>Table: <code>TeamStats</code></p> <pre> +------------------+---------+ | Column Name | Type | +------------------+---------+ | team_id | int | | team_name | varchar | | matches_played | int | | wins | int | | draws | int | | losses | int | +------------------+---------+ team_id is the unique key for this table. This table contains team id, team name, matches_played, wins, draws, and losses. </pre> <p>Write a solution to calculate the <strong>points</strong>, <strong>position</strong>, and <strong>tier</strong> for each team in the league. Points are calculated as follows:</p> <ul> <li><code>3</code> points for a <strong>win</strong></li> <li><code>1</code> point for a <strong>draw</strong></li> <li><code>0</code> points for a <strong>loss</strong></li> </ul> <p><strong>Note:</strong>&nbsp;Teams with the same points must be assigned the same position.</p> <p><strong>Tier ranking:</strong></p> <ul> <li>Divide the league into <code>3</code> tiers based on points:</li> <li>Tier 1: Top <code>33%</code> of teams</li> <li>Tier 2: Middle <code>33%</code> of teams</li> <li>Tier 3: Bottom<code> 34%</code> of teams</li> <li>In case of <strong>ties</strong> at<strong> tier boundaries</strong>, place tied teams in the <strong>higher tier</strong>.</li> </ul> <p>Return <em>the result table </em><em>ordered by</em> <code>points</code>&nbsp;<em>in&nbsp;<strong>descending</strong>,<strong>&nbsp;</strong>and then by</em> <code>team_name</code> <em>in <strong>ascending</strong> order.</em></p> <p>The query result format is in the following example.</p> <p>&nbsp;</p> <p><strong class="example">Example:</strong></p> <div class="example-block"> <p><strong>Input:</strong></p> <p><code>TeamStats</code> table:</p> <pre class="example-io"> +---------+-------------------+----------------+------+-------+--------+ | team_id | team_name | matches_played | wins | draws | losses | +---------+-------------------+----------------+------+-------+--------+ | 1 | Chelsea | 22 | 13 | 2 | 7 | | 2 | Nottingham Forest | 27 | 6 | 6 | 15 | | 3 | Liverpool | 17 | 1 | 8 | 8 | | 4 | Aston Villa | 20 | 1 | 6 | 13 | | 5 | Fulham | 31 | 18 | 1 | 12 | | 6 | Burnley | 26 | 6 | 9 | 11 | | 7 | Newcastle United | 33 | 11 | 10 | 12 | | 8 | Sheffield United | 20 | 18 | 2 | 0 | | 9 | Luton Town | 5 | 4 | 0 | 1 | | 10 | Everton | 14 | 2 | 6 | 6 | +---------+-------------------+----------------+------+-------+--------+ </pre> <p><strong>Output:</strong></p> <pre class="example-io"> +-------------------+--------+----------+---------+ | team_name | points | position | tier | +-------------------+--------+----------+---------+ | Sheffield United | 56 | 1 | Tier 1 | | Fulham | 55 | 2 | Tier 1 | | Newcastle United | 43 | 3 | Tier 1 | | Chelsea | 41 | 4 | Tier 1 | | Burnley | 27 | 5 | Tier 2 | | Nottingham Forest | 24 | 6 | Tier 2 | | Everton | 12 | 7 | Tier 2 | | Luton Town | 12 | 7 | Tier 2 | | Liverpool | 11 | 9 | Tier 3 | | Aston Villa | 9 | 10 | Tier 3 | +-------------------+--------+----------+---------+ </pre> <p><strong>Explanation:</strong></p> <ul> <li>Sheffield United has 56 points (18 wins * 3 points + 2 draws * 1 point) and is in position 1.</li> <li>Fulham has 55 points (18 wins * 3 points + 1 draw * 1 point) and is in position 2.</li> <li>Newcastle United has 43 points (11 wins * 3 points + 10 draws * 1 point) and is in position 3.</li> <li>Chelsea has 41 points (13 wins * 3 points + 2 draws * 1 point) and is in position 4.</li> <li>Burnley has 27 points (6 wins * 3 points + 9 draws * 1 point) and is in position 5.</li> <li>Nottingham Forest has 24 points (6 wins * 3 points + 6 draws * 1 point) and is in position 6.</li> <li>Everton and Luton Town both have 12 points, with Everton having 2 wins * 3 points + 6 draws * 1 point, and Luton Town having 4 wins * 3 points. Both teams share position 7.</li> <li>Liverpool has 11 points (1 win * 3 points + 8 draws * 1 point) and is in position 9.</li> <li>Aston Villa has 9 points (1 win * 3 points + 6 draws * 1 point) and is in position 10.</li> </ul> <p><strong>Tier Calculation:</strong></p> <ul> <li><strong>Tier 1:</strong> The top 33% of teams based on points. Sheffield United, Fulham, Newcastle United, and Chelsea fall into Tier 1.</li> <li><strong>Tier 2:</strong> The middle 33% of teams. Burnley, Nottingham Forest, Everton, and Luton Town fall into Tier 2.</li> <li><strong>Tier 3:</strong> The bottom 34% of teams. Liverpool and Aston Villa fall into Tier 3.</li> </ul> </div>
Database
SQL
WITH T AS ( SELECT team_name, wins * 3 + draws AS points, RANK() OVER (ORDER BY wins * 3 + draws DESC) AS position, COUNT(1) OVER () AS total_teams FROM TeamStats ) SELECT team_name, points, position, CASE WHEN position <= CEIL(total_teams / 3.0) THEN 'Tier 1' WHEN position <= CEIL(2 * total_teams / 3.0) THEN 'Tier 2' ELSE 'Tier 3' END tier FROM T ORDER BY 2 DESC, 1;
3,253
Construct String with Minimum Cost (Easy)
Medium
<p>You are given a string <code>target</code>, an array of strings <code>words</code>, and an integer array <code>costs</code>, both arrays of the same length.</p> <p>Imagine an empty string <code>s</code>.</p> <p>You can perform the following operation any number of times (including <strong>zero</strong>):</p> <ul> <li>Choose an index <code>i</code> in the range <code>[0, words.length - 1]</code>.</li> <li>Append <code>words[i]</code> to <code>s</code>.</li> <li>The cost of operation is <code>costs[i]</code>.</li> </ul> <p>Return the <strong>minimum</strong> cost to make <code>s</code> equal to <code>target</code>. If it&#39;s not possible, return -1.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">target = &quot;abcdef&quot;, words = [&quot;abdef&quot;,&quot;abc&quot;,&quot;d&quot;,&quot;def&quot;,&quot;ef&quot;], costs = [100,1,1,10,5]</span></p> <p><strong>Output:</strong> <span class="example-io">7</span></p> <p><strong>Explanation:</strong></p> <p>The minimum cost can be achieved by performing the following operations:</p> <ul> <li>Select index 1 and append <code>&quot;abc&quot;</code> to <code>s</code> at a cost of 1, resulting in <code>s = &quot;abc&quot;</code>.</li> <li>Select index 2 and append <code>&quot;d&quot;</code> to <code>s</code> at a cost of 1, resulting in <code>s = &quot;abcd&quot;</code>.</li> <li>Select index 4 and append <code>&quot;ef&quot;</code> to <code>s</code> at a cost of 5, resulting in <code>s = &quot;abcdef&quot;</code>.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">target = &quot;aaaa&quot;, words = [&quot;z&quot;,&quot;zz&quot;,&quot;zzz&quot;], costs = [1,10,100]</span></p> <p><strong>Output:</strong> <span class="example-io">-1</span></p> <p><strong>Explanation:</strong></p> <p>It is impossible to make <code>s</code> equal to <code>target</code>, so we return -1.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= target.length &lt;= 2000</code></li> <li><code>1 &lt;= words.length == costs.length &lt;= 50</code></li> <li><code>1 &lt;= words[i].length &lt;= target.length</code></li> <li><code>target</code> and <code>words[i]</code> consist only of lowercase English letters.</li> <li><code>1 &lt;= costs[i] &lt;= 10<sup>5</sup></code></li> </ul>
C++
const int inf = 1 << 29; class Trie { public: Trie* children[26]{}; int cost = inf; void insert(string& word, int cost) { Trie* node = this; for (char c : word) { int idx = c - 'a'; if (!node->children[idx]) { node->children[idx] = new Trie(); } node = node->children[idx]; } node->cost = min(node->cost, cost); } }; class Solution { public: int minimumCost(string target, vector<string>& words, vector<int>& costs) { Trie* trie = new Trie(); for (int i = 0; i < words.size(); ++i) { trie->insert(words[i], costs[i]); } int n = target.length(); int f[n]; memset(f, 0, sizeof(f)); auto dfs = [&](this auto&& dfs, int i) -> int { if (i >= n) { return 0; } if (f[i]) { return f[i]; } f[i] = inf; Trie* node = trie; for (int j = i; j < n; ++j) { int idx = target[j] - 'a'; if (!node->children[idx]) { return f[i]; } node = node->children[idx]; f[i] = min(f[i], node->cost + dfs(j + 1)); } return f[i]; }; int ans = dfs(0); return ans < inf ? ans : -1; } };
3,253
Construct String with Minimum Cost (Easy)
Medium
<p>You are given a string <code>target</code>, an array of strings <code>words</code>, and an integer array <code>costs</code>, both arrays of the same length.</p> <p>Imagine an empty string <code>s</code>.</p> <p>You can perform the following operation any number of times (including <strong>zero</strong>):</p> <ul> <li>Choose an index <code>i</code> in the range <code>[0, words.length - 1]</code>.</li> <li>Append <code>words[i]</code> to <code>s</code>.</li> <li>The cost of operation is <code>costs[i]</code>.</li> </ul> <p>Return the <strong>minimum</strong> cost to make <code>s</code> equal to <code>target</code>. If it&#39;s not possible, return -1.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">target = &quot;abcdef&quot;, words = [&quot;abdef&quot;,&quot;abc&quot;,&quot;d&quot;,&quot;def&quot;,&quot;ef&quot;], costs = [100,1,1,10,5]</span></p> <p><strong>Output:</strong> <span class="example-io">7</span></p> <p><strong>Explanation:</strong></p> <p>The minimum cost can be achieved by performing the following operations:</p> <ul> <li>Select index 1 and append <code>&quot;abc&quot;</code> to <code>s</code> at a cost of 1, resulting in <code>s = &quot;abc&quot;</code>.</li> <li>Select index 2 and append <code>&quot;d&quot;</code> to <code>s</code> at a cost of 1, resulting in <code>s = &quot;abcd&quot;</code>.</li> <li>Select index 4 and append <code>&quot;ef&quot;</code> to <code>s</code> at a cost of 5, resulting in <code>s = &quot;abcdef&quot;</code>.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">target = &quot;aaaa&quot;, words = [&quot;z&quot;,&quot;zz&quot;,&quot;zzz&quot;], costs = [1,10,100]</span></p> <p><strong>Output:</strong> <span class="example-io">-1</span></p> <p><strong>Explanation:</strong></p> <p>It is impossible to make <code>s</code> equal to <code>target</code>, so we return -1.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= target.length &lt;= 2000</code></li> <li><code>1 &lt;= words.length == costs.length &lt;= 50</code></li> <li><code>1 &lt;= words[i].length &lt;= target.length</code></li> <li><code>target</code> and <code>words[i]</code> consist only of lowercase English letters.</li> <li><code>1 &lt;= costs[i] &lt;= 10<sup>5</sup></code></li> </ul>
Go
const inf = 1 << 29 type Trie struct { children [26]*Trie cost int } func NewTrie() *Trie { return &Trie{cost: inf} } func (t *Trie) insert(word string, cost int) { node := t for _, c := range word { idx := c - 'a' if node.children[idx] == nil { node.children[idx] = NewTrie() } node = node.children[idx] } node.cost = min(node.cost, cost) } func minimumCost(target string, words []string, costs []int) int { trie := NewTrie() for i, word := range words { trie.insert(word, costs[i]) } n := len(target) f := make([]int, n) var dfs func(int) int dfs = func(i int) int { if i >= n { return 0 } if f[i] != 0 { return f[i] } f[i] = inf node := trie for j := i; j < n; j++ { idx := target[j] - 'a' if node.children[idx] == nil { return f[i] } node = node.children[idx] f[i] = min(f[i], node.cost+dfs(j+1)) } return f[i] } if ans := dfs(0); ans < inf { return ans } return -1 }
3,253
Construct String with Minimum Cost (Easy)
Medium
<p>You are given a string <code>target</code>, an array of strings <code>words</code>, and an integer array <code>costs</code>, both arrays of the same length.</p> <p>Imagine an empty string <code>s</code>.</p> <p>You can perform the following operation any number of times (including <strong>zero</strong>):</p> <ul> <li>Choose an index <code>i</code> in the range <code>[0, words.length - 1]</code>.</li> <li>Append <code>words[i]</code> to <code>s</code>.</li> <li>The cost of operation is <code>costs[i]</code>.</li> </ul> <p>Return the <strong>minimum</strong> cost to make <code>s</code> equal to <code>target</code>. If it&#39;s not possible, return -1.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">target = &quot;abcdef&quot;, words = [&quot;abdef&quot;,&quot;abc&quot;,&quot;d&quot;,&quot;def&quot;,&quot;ef&quot;], costs = [100,1,1,10,5]</span></p> <p><strong>Output:</strong> <span class="example-io">7</span></p> <p><strong>Explanation:</strong></p> <p>The minimum cost can be achieved by performing the following operations:</p> <ul> <li>Select index 1 and append <code>&quot;abc&quot;</code> to <code>s</code> at a cost of 1, resulting in <code>s = &quot;abc&quot;</code>.</li> <li>Select index 2 and append <code>&quot;d&quot;</code> to <code>s</code> at a cost of 1, resulting in <code>s = &quot;abcd&quot;</code>.</li> <li>Select index 4 and append <code>&quot;ef&quot;</code> to <code>s</code> at a cost of 5, resulting in <code>s = &quot;abcdef&quot;</code>.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">target = &quot;aaaa&quot;, words = [&quot;z&quot;,&quot;zz&quot;,&quot;zzz&quot;], costs = [1,10,100]</span></p> <p><strong>Output:</strong> <span class="example-io">-1</span></p> <p><strong>Explanation:</strong></p> <p>It is impossible to make <code>s</code> equal to <code>target</code>, so we return -1.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= target.length &lt;= 2000</code></li> <li><code>1 &lt;= words.length == costs.length &lt;= 50</code></li> <li><code>1 &lt;= words[i].length &lt;= target.length</code></li> <li><code>target</code> and <code>words[i]</code> consist only of lowercase English letters.</li> <li><code>1 &lt;= costs[i] &lt;= 10<sup>5</sup></code></li> </ul>
Java
class Trie { public final int inf = 1 << 29; public Trie[] children = new Trie[26]; public int cost = inf; public void insert(String word, int cost) { Trie node = this; for (char c : word.toCharArray()) { int idx = c - 'a'; if (node.children[idx] == null) { node.children[idx] = new Trie(); } node = node.children[idx]; } node.cost = Math.min(node.cost, cost); } } class Solution { private Trie trie = new Trie(); private char[] target; private Integer[] f; public int minimumCost(String target, String[] words, int[] costs) { for (int i = 0; i < words.length; ++i) { trie.insert(words[i], costs[i]); } this.target = target.toCharArray(); f = new Integer[target.length()]; int ans = dfs(0); return ans < trie.inf ? ans : -1; } private int dfs(int i) { if (i >= target.length) { return 0; } if (f[i] != null) { return f[i]; } f[i] = trie.inf; Trie node = trie; for (int j = i; j < target.length; ++j) { int idx = target[j] - 'a'; if (node.children[idx] == null) { return f[i]; } node = node.children[idx]; f[i] = Math.min(f[i], node.cost + dfs(j + 1)); } return f[i]; } }
3,253
Construct String with Minimum Cost (Easy)
Medium
<p>You are given a string <code>target</code>, an array of strings <code>words</code>, and an integer array <code>costs</code>, both arrays of the same length.</p> <p>Imagine an empty string <code>s</code>.</p> <p>You can perform the following operation any number of times (including <strong>zero</strong>):</p> <ul> <li>Choose an index <code>i</code> in the range <code>[0, words.length - 1]</code>.</li> <li>Append <code>words[i]</code> to <code>s</code>.</li> <li>The cost of operation is <code>costs[i]</code>.</li> </ul> <p>Return the <strong>minimum</strong> cost to make <code>s</code> equal to <code>target</code>. If it&#39;s not possible, return -1.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">target = &quot;abcdef&quot;, words = [&quot;abdef&quot;,&quot;abc&quot;,&quot;d&quot;,&quot;def&quot;,&quot;ef&quot;], costs = [100,1,1,10,5]</span></p> <p><strong>Output:</strong> <span class="example-io">7</span></p> <p><strong>Explanation:</strong></p> <p>The minimum cost can be achieved by performing the following operations:</p> <ul> <li>Select index 1 and append <code>&quot;abc&quot;</code> to <code>s</code> at a cost of 1, resulting in <code>s = &quot;abc&quot;</code>.</li> <li>Select index 2 and append <code>&quot;d&quot;</code> to <code>s</code> at a cost of 1, resulting in <code>s = &quot;abcd&quot;</code>.</li> <li>Select index 4 and append <code>&quot;ef&quot;</code> to <code>s</code> at a cost of 5, resulting in <code>s = &quot;abcdef&quot;</code>.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">target = &quot;aaaa&quot;, words = [&quot;z&quot;,&quot;zz&quot;,&quot;zzz&quot;], costs = [1,10,100]</span></p> <p><strong>Output:</strong> <span class="example-io">-1</span></p> <p><strong>Explanation:</strong></p> <p>It is impossible to make <code>s</code> equal to <code>target</code>, so we return -1.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= target.length &lt;= 2000</code></li> <li><code>1 &lt;= words.length == costs.length &lt;= 50</code></li> <li><code>1 &lt;= words[i].length &lt;= target.length</code></li> <li><code>target</code> and <code>words[i]</code> consist only of lowercase English letters.</li> <li><code>1 &lt;= costs[i] &lt;= 10<sup>5</sup></code></li> </ul>
Python
class Trie: def __init__(self): self.children: List[Optional[Trie]] = [None] * 26 self.cost = inf def insert(self, word: str, cost: int): node = self for c in word: idx = ord(c) - ord("a") if node.children[idx] is None: node.children[idx] = Trie() node = node.children[idx] node.cost = min(node.cost, cost) class Solution: def minimumCost(self, target: str, words: List[str], costs: List[int]) -> int: @cache def dfs(i: int) -> int: if i >= len(target): return 0 ans = inf node = trie for j in range(i, len(target)): idx = ord(target[j]) - ord("a") if node.children[idx] is None: return ans node = node.children[idx] ans = min(ans, node.cost + dfs(j + 1)) return ans trie = Trie() for word, cost in zip(words, costs): trie.insert(word, cost) ans = dfs(0) return ans if ans < inf else -1
3,253
Construct String with Minimum Cost (Easy)
Medium
<p>You are given a string <code>target</code>, an array of strings <code>words</code>, and an integer array <code>costs</code>, both arrays of the same length.</p> <p>Imagine an empty string <code>s</code>.</p> <p>You can perform the following operation any number of times (including <strong>zero</strong>):</p> <ul> <li>Choose an index <code>i</code> in the range <code>[0, words.length - 1]</code>.</li> <li>Append <code>words[i]</code> to <code>s</code>.</li> <li>The cost of operation is <code>costs[i]</code>.</li> </ul> <p>Return the <strong>minimum</strong> cost to make <code>s</code> equal to <code>target</code>. If it&#39;s not possible, return -1.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">target = &quot;abcdef&quot;, words = [&quot;abdef&quot;,&quot;abc&quot;,&quot;d&quot;,&quot;def&quot;,&quot;ef&quot;], costs = [100,1,1,10,5]</span></p> <p><strong>Output:</strong> <span class="example-io">7</span></p> <p><strong>Explanation:</strong></p> <p>The minimum cost can be achieved by performing the following operations:</p> <ul> <li>Select index 1 and append <code>&quot;abc&quot;</code> to <code>s</code> at a cost of 1, resulting in <code>s = &quot;abc&quot;</code>.</li> <li>Select index 2 and append <code>&quot;d&quot;</code> to <code>s</code> at a cost of 1, resulting in <code>s = &quot;abcd&quot;</code>.</li> <li>Select index 4 and append <code>&quot;ef&quot;</code> to <code>s</code> at a cost of 5, resulting in <code>s = &quot;abcdef&quot;</code>.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">target = &quot;aaaa&quot;, words = [&quot;z&quot;,&quot;zz&quot;,&quot;zzz&quot;], costs = [1,10,100]</span></p> <p><strong>Output:</strong> <span class="example-io">-1</span></p> <p><strong>Explanation:</strong></p> <p>It is impossible to make <code>s</code> equal to <code>target</code>, so we return -1.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= target.length &lt;= 2000</code></li> <li><code>1 &lt;= words.length == costs.length &lt;= 50</code></li> <li><code>1 &lt;= words[i].length &lt;= target.length</code></li> <li><code>target</code> and <code>words[i]</code> consist only of lowercase English letters.</li> <li><code>1 &lt;= costs[i] &lt;= 10<sup>5</sup></code></li> </ul>
TypeScript
const inf = 1 << 29; class Trie { children: (Trie | null)[]; cost: number; constructor() { this.children = Array(26).fill(null); this.cost = inf; } insert(word: string, cost: number): void { let node: Trie = this; for (const c of word) { const idx = c.charCodeAt(0) - 97; if (!node.children[idx]) { node.children[idx] = new Trie(); } node = node.children[idx]!; } node.cost = Math.min(node.cost, cost); } } function minimumCost(target: string, words: string[], costs: number[]): number { const trie = new Trie(); for (let i = 0; i < words.length; ++i) { trie.insert(words[i], costs[i]); } const n = target.length; const f: number[] = Array(n).fill(0); const dfs = (i: number): number => { if (i >= n) { return 0; } if (f[i]) { return f[i]; } f[i] = inf; let node: Trie | null = trie; for (let j = i; j < n; ++j) { const idx = target.charCodeAt(j) - 97; if (!node?.children[idx]) { return f[i]; } node = node.children[idx]; f[i] = Math.min(f[i], node!.cost + dfs(j + 1)); } return f[i]; }; const ans = dfs(0); return ans < inf ? ans : -1; }
3,254
Find the Power of K-Size Subarrays I
Medium
<p>You are given an array of integers <code>nums</code> of length <code>n</code> and a <em>positive</em> integer <code>k</code>.</p> <p>The <strong>power</strong> of an array is defined as:</p> <ul> <li>Its <strong>maximum</strong> element if <em>all</em> of its elements are <strong>consecutive</strong> and <strong>sorted</strong> in <strong>ascending</strong> order.</li> <li>-1 otherwise.</li> </ul> <p>You need to find the <strong>power</strong> of all <span data-keyword="subarray-nonempty">subarrays</span> of <code>nums</code> of size <code>k</code>.</p> <p>Return an integer array <code>results</code> of size <code>n - k + 1</code>, where <code>results[i]</code> is the <em>power</em> of <code>nums[i..(i + k - 1)]</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,2,3,4,3,2,5], k = 3</span></p> <p><strong>Output:</strong> [3,4,-1,-1,-1]</p> <p><strong>Explanation:</strong></p> <p>There are 5 subarrays of <code>nums</code> of size 3:</p> <ul> <li><code>[1, 2, 3]</code> with the maximum element 3.</li> <li><code>[2, 3, 4]</code> with the maximum element 4.</li> <li><code>[3, 4, 3]</code> whose elements are <strong>not</strong> consecutive.</li> <li><code>[4, 3, 2]</code> whose elements are <strong>not</strong> sorted.</li> <li><code>[3, 2, 5]</code> whose elements are <strong>not</strong> consecutive.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,2,2,2,2], k = 4</span></p> <p><strong>Output:</strong> <span class="example-io">[-1,-1]</span></p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [3,2,3,2,3,2], k = 2</span></p> <p><strong>Output:</strong> <span class="example-io">[-1,3,-1,3,-1]</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == nums.length &lt;= 500</code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= k &lt;= n</code></li> </ul>
Array; Sliding Window
C++
class Solution { public: vector<int> resultsArray(vector<int>& nums, int k) { int n = nums.size(); int f[n]; f[0] = 1; for (int i = 1; i < n; ++i) { f[i] = nums[i] == nums[i - 1] + 1 ? f[i - 1] + 1 : 1; } vector<int> ans; for (int i = k - 1; i < n; ++i) { ans.push_back(f[i] >= k ? nums[i] : -1); } return ans; } };
3,254
Find the Power of K-Size Subarrays I
Medium
<p>You are given an array of integers <code>nums</code> of length <code>n</code> and a <em>positive</em> integer <code>k</code>.</p> <p>The <strong>power</strong> of an array is defined as:</p> <ul> <li>Its <strong>maximum</strong> element if <em>all</em> of its elements are <strong>consecutive</strong> and <strong>sorted</strong> in <strong>ascending</strong> order.</li> <li>-1 otherwise.</li> </ul> <p>You need to find the <strong>power</strong> of all <span data-keyword="subarray-nonempty">subarrays</span> of <code>nums</code> of size <code>k</code>.</p> <p>Return an integer array <code>results</code> of size <code>n - k + 1</code>, where <code>results[i]</code> is the <em>power</em> of <code>nums[i..(i + k - 1)]</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,2,3,4,3,2,5], k = 3</span></p> <p><strong>Output:</strong> [3,4,-1,-1,-1]</p> <p><strong>Explanation:</strong></p> <p>There are 5 subarrays of <code>nums</code> of size 3:</p> <ul> <li><code>[1, 2, 3]</code> with the maximum element 3.</li> <li><code>[2, 3, 4]</code> with the maximum element 4.</li> <li><code>[3, 4, 3]</code> whose elements are <strong>not</strong> consecutive.</li> <li><code>[4, 3, 2]</code> whose elements are <strong>not</strong> sorted.</li> <li><code>[3, 2, 5]</code> whose elements are <strong>not</strong> consecutive.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,2,2,2,2], k = 4</span></p> <p><strong>Output:</strong> <span class="example-io">[-1,-1]</span></p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [3,2,3,2,3,2], k = 2</span></p> <p><strong>Output:</strong> <span class="example-io">[-1,3,-1,3,-1]</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == nums.length &lt;= 500</code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= k &lt;= n</code></li> </ul>
Array; Sliding Window
Go
func resultsArray(nums []int, k int) (ans []int) { n := len(nums) f := make([]int, n) f[0] = 1 for i := 1; i < n; i++ { if nums[i] == nums[i-1]+1 { f[i] = f[i-1] + 1 } else { f[i] = 1 } } for i := k - 1; i < n; i++ { if f[i] >= k { ans = append(ans, nums[i]) } else { ans = append(ans, -1) } } return }
3,254
Find the Power of K-Size Subarrays I
Medium
<p>You are given an array of integers <code>nums</code> of length <code>n</code> and a <em>positive</em> integer <code>k</code>.</p> <p>The <strong>power</strong> of an array is defined as:</p> <ul> <li>Its <strong>maximum</strong> element if <em>all</em> of its elements are <strong>consecutive</strong> and <strong>sorted</strong> in <strong>ascending</strong> order.</li> <li>-1 otherwise.</li> </ul> <p>You need to find the <strong>power</strong> of all <span data-keyword="subarray-nonempty">subarrays</span> of <code>nums</code> of size <code>k</code>.</p> <p>Return an integer array <code>results</code> of size <code>n - k + 1</code>, where <code>results[i]</code> is the <em>power</em> of <code>nums[i..(i + k - 1)]</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,2,3,4,3,2,5], k = 3</span></p> <p><strong>Output:</strong> [3,4,-1,-1,-1]</p> <p><strong>Explanation:</strong></p> <p>There are 5 subarrays of <code>nums</code> of size 3:</p> <ul> <li><code>[1, 2, 3]</code> with the maximum element 3.</li> <li><code>[2, 3, 4]</code> with the maximum element 4.</li> <li><code>[3, 4, 3]</code> whose elements are <strong>not</strong> consecutive.</li> <li><code>[4, 3, 2]</code> whose elements are <strong>not</strong> sorted.</li> <li><code>[3, 2, 5]</code> whose elements are <strong>not</strong> consecutive.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,2,2,2,2], k = 4</span></p> <p><strong>Output:</strong> <span class="example-io">[-1,-1]</span></p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [3,2,3,2,3,2], k = 2</span></p> <p><strong>Output:</strong> <span class="example-io">[-1,3,-1,3,-1]</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == nums.length &lt;= 500</code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= k &lt;= n</code></li> </ul>
Array; Sliding Window
Java
class Solution { public int[] resultsArray(int[] nums, int k) { int n = nums.length; int[] f = new int[n]; Arrays.fill(f, 1); for (int i = 1; i < n; ++i) { if (nums[i] == nums[i - 1] + 1) { f[i] = f[i - 1] + 1; } } int[] ans = new int[n - k + 1]; for (int i = k - 1; i < n; ++i) { ans[i - k + 1] = f[i] >= k ? nums[i] : -1; } return ans; } }
3,254
Find the Power of K-Size Subarrays I
Medium
<p>You are given an array of integers <code>nums</code> of length <code>n</code> and a <em>positive</em> integer <code>k</code>.</p> <p>The <strong>power</strong> of an array is defined as:</p> <ul> <li>Its <strong>maximum</strong> element if <em>all</em> of its elements are <strong>consecutive</strong> and <strong>sorted</strong> in <strong>ascending</strong> order.</li> <li>-1 otherwise.</li> </ul> <p>You need to find the <strong>power</strong> of all <span data-keyword="subarray-nonempty">subarrays</span> of <code>nums</code> of size <code>k</code>.</p> <p>Return an integer array <code>results</code> of size <code>n - k + 1</code>, where <code>results[i]</code> is the <em>power</em> of <code>nums[i..(i + k - 1)]</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,2,3,4,3,2,5], k = 3</span></p> <p><strong>Output:</strong> [3,4,-1,-1,-1]</p> <p><strong>Explanation:</strong></p> <p>There are 5 subarrays of <code>nums</code> of size 3:</p> <ul> <li><code>[1, 2, 3]</code> with the maximum element 3.</li> <li><code>[2, 3, 4]</code> with the maximum element 4.</li> <li><code>[3, 4, 3]</code> whose elements are <strong>not</strong> consecutive.</li> <li><code>[4, 3, 2]</code> whose elements are <strong>not</strong> sorted.</li> <li><code>[3, 2, 5]</code> whose elements are <strong>not</strong> consecutive.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,2,2,2,2], k = 4</span></p> <p><strong>Output:</strong> <span class="example-io">[-1,-1]</span></p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [3,2,3,2,3,2], k = 2</span></p> <p><strong>Output:</strong> <span class="example-io">[-1,3,-1,3,-1]</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == nums.length &lt;= 500</code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= k &lt;= n</code></li> </ul>
Array; Sliding Window
Python
class Solution: def resultsArray(self, nums: List[int], k: int) -> List[int]: n = len(nums) f = [1] * n for i in range(1, n): if nums[i] == nums[i - 1] + 1: f[i] = f[i - 1] + 1 return [nums[i] if f[i] >= k else -1 for i in range(k - 1, n)]
3,254
Find the Power of K-Size Subarrays I
Medium
<p>You are given an array of integers <code>nums</code> of length <code>n</code> and a <em>positive</em> integer <code>k</code>.</p> <p>The <strong>power</strong> of an array is defined as:</p> <ul> <li>Its <strong>maximum</strong> element if <em>all</em> of its elements are <strong>consecutive</strong> and <strong>sorted</strong> in <strong>ascending</strong> order.</li> <li>-1 otherwise.</li> </ul> <p>You need to find the <strong>power</strong> of all <span data-keyword="subarray-nonempty">subarrays</span> of <code>nums</code> of size <code>k</code>.</p> <p>Return an integer array <code>results</code> of size <code>n - k + 1</code>, where <code>results[i]</code> is the <em>power</em> of <code>nums[i..(i + k - 1)]</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,2,3,4,3,2,5], k = 3</span></p> <p><strong>Output:</strong> [3,4,-1,-1,-1]</p> <p><strong>Explanation:</strong></p> <p>There are 5 subarrays of <code>nums</code> of size 3:</p> <ul> <li><code>[1, 2, 3]</code> with the maximum element 3.</li> <li><code>[2, 3, 4]</code> with the maximum element 4.</li> <li><code>[3, 4, 3]</code> whose elements are <strong>not</strong> consecutive.</li> <li><code>[4, 3, 2]</code> whose elements are <strong>not</strong> sorted.</li> <li><code>[3, 2, 5]</code> whose elements are <strong>not</strong> consecutive.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,2,2,2,2], k = 4</span></p> <p><strong>Output:</strong> <span class="example-io">[-1,-1]</span></p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [3,2,3,2,3,2], k = 2</span></p> <p><strong>Output:</strong> <span class="example-io">[-1,3,-1,3,-1]</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == nums.length &lt;= 500</code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= k &lt;= n</code></li> </ul>
Array; Sliding Window
TypeScript
function resultsArray(nums: number[], k: number): number[] { const n = nums.length; const f: number[] = Array(n).fill(1); for (let i = 1; i < n; ++i) { if (nums[i] === nums[i - 1] + 1) { f[i] = f[i - 1] + 1; } } const ans: number[] = []; for (let i = k - 1; i < n; ++i) { ans.push(f[i] >= k ? nums[i] : -1); } return ans; }
3,255
Find the Power of K-Size Subarrays II
Medium
<p>You are given an array of integers <code>nums</code> of length <code>n</code> and a <em>positive</em> integer <code>k</code>.</p> <p>The <strong>power</strong> of an array is defined as:</p> <ul> <li>Its <strong>maximum</strong> element if <em>all</em> of its elements are <strong>consecutive</strong> and <strong>sorted</strong> in <strong>ascending</strong> order.</li> <li>-1 otherwise.</li> </ul> <p>You need to find the <strong>power</strong> of all <span data-keyword="subarray-nonempty">subarrays</span> of <code>nums</code> of size <code>k</code>.</p> <p>Return an integer array <code>results</code> of size <code>n - k + 1</code>, where <code>results[i]</code> is the <em>power</em> of <code>nums[i..(i + k - 1)]</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,2,3,4,3,2,5], k = 3</span></p> <p><strong>Output:</strong> [3,4,-1,-1,-1]</p> <p><strong>Explanation:</strong></p> <p>There are 5 subarrays of <code>nums</code> of size 3:</p> <ul> <li><code>[1, 2, 3]</code> with the maximum element 3.</li> <li><code>[2, 3, 4]</code> with the maximum element 4.</li> <li><code>[3, 4, 3]</code> whose elements are <strong>not</strong> consecutive.</li> <li><code>[4, 3, 2]</code> whose elements are <strong>not</strong> sorted.</li> <li><code>[3, 2, 5]</code> whose elements are <strong>not</strong> consecutive.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,2,2,2,2], k = 4</span></p> <p><strong>Output:</strong> <span class="example-io">[-1,-1]</span></p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [3,2,3,2,3,2], k = 2</span></p> <p><strong>Output:</strong> <span class="example-io">[-1,3,-1,3,-1]</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == nums.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>6</sup></code></li> <li><code>1 &lt;= k &lt;= n</code></li> </ul>
Array; Sliding Window
C++
class Solution { public: vector<int> resultsArray(vector<int>& nums, int k) { int n = nums.size(); int f[n]; f[0] = 1; for (int i = 1; i < n; ++i) { f[i] = nums[i] == nums[i - 1] + 1 ? f[i - 1] + 1 : 1; } vector<int> ans; for (int i = k - 1; i < n; ++i) { ans.push_back(f[i] >= k ? nums[i] : -1); } return ans; } };
3,255
Find the Power of K-Size Subarrays II
Medium
<p>You are given an array of integers <code>nums</code> of length <code>n</code> and a <em>positive</em> integer <code>k</code>.</p> <p>The <strong>power</strong> of an array is defined as:</p> <ul> <li>Its <strong>maximum</strong> element if <em>all</em> of its elements are <strong>consecutive</strong> and <strong>sorted</strong> in <strong>ascending</strong> order.</li> <li>-1 otherwise.</li> </ul> <p>You need to find the <strong>power</strong> of all <span data-keyword="subarray-nonempty">subarrays</span> of <code>nums</code> of size <code>k</code>.</p> <p>Return an integer array <code>results</code> of size <code>n - k + 1</code>, where <code>results[i]</code> is the <em>power</em> of <code>nums[i..(i + k - 1)]</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,2,3,4,3,2,5], k = 3</span></p> <p><strong>Output:</strong> [3,4,-1,-1,-1]</p> <p><strong>Explanation:</strong></p> <p>There are 5 subarrays of <code>nums</code> of size 3:</p> <ul> <li><code>[1, 2, 3]</code> with the maximum element 3.</li> <li><code>[2, 3, 4]</code> with the maximum element 4.</li> <li><code>[3, 4, 3]</code> whose elements are <strong>not</strong> consecutive.</li> <li><code>[4, 3, 2]</code> whose elements are <strong>not</strong> sorted.</li> <li><code>[3, 2, 5]</code> whose elements are <strong>not</strong> consecutive.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,2,2,2,2], k = 4</span></p> <p><strong>Output:</strong> <span class="example-io">[-1,-1]</span></p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [3,2,3,2,3,2], k = 2</span></p> <p><strong>Output:</strong> <span class="example-io">[-1,3,-1,3,-1]</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == nums.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>6</sup></code></li> <li><code>1 &lt;= k &lt;= n</code></li> </ul>
Array; Sliding Window
Go
func resultsArray(nums []int, k int) (ans []int) { n := len(nums) f := make([]int, n) f[0] = 1 for i := 1; i < n; i++ { if nums[i] == nums[i-1]+1 { f[i] = f[i-1] + 1 } else { f[i] = 1 } } for i := k - 1; i < n; i++ { if f[i] >= k { ans = append(ans, nums[i]) } else { ans = append(ans, -1) } } return }
3,255
Find the Power of K-Size Subarrays II
Medium
<p>You are given an array of integers <code>nums</code> of length <code>n</code> and a <em>positive</em> integer <code>k</code>.</p> <p>The <strong>power</strong> of an array is defined as:</p> <ul> <li>Its <strong>maximum</strong> element if <em>all</em> of its elements are <strong>consecutive</strong> and <strong>sorted</strong> in <strong>ascending</strong> order.</li> <li>-1 otherwise.</li> </ul> <p>You need to find the <strong>power</strong> of all <span data-keyword="subarray-nonempty">subarrays</span> of <code>nums</code> of size <code>k</code>.</p> <p>Return an integer array <code>results</code> of size <code>n - k + 1</code>, where <code>results[i]</code> is the <em>power</em> of <code>nums[i..(i + k - 1)]</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,2,3,4,3,2,5], k = 3</span></p> <p><strong>Output:</strong> [3,4,-1,-1,-1]</p> <p><strong>Explanation:</strong></p> <p>There are 5 subarrays of <code>nums</code> of size 3:</p> <ul> <li><code>[1, 2, 3]</code> with the maximum element 3.</li> <li><code>[2, 3, 4]</code> with the maximum element 4.</li> <li><code>[3, 4, 3]</code> whose elements are <strong>not</strong> consecutive.</li> <li><code>[4, 3, 2]</code> whose elements are <strong>not</strong> sorted.</li> <li><code>[3, 2, 5]</code> whose elements are <strong>not</strong> consecutive.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,2,2,2,2], k = 4</span></p> <p><strong>Output:</strong> <span class="example-io">[-1,-1]</span></p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [3,2,3,2,3,2], k = 2</span></p> <p><strong>Output:</strong> <span class="example-io">[-1,3,-1,3,-1]</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == nums.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>6</sup></code></li> <li><code>1 &lt;= k &lt;= n</code></li> </ul>
Array; Sliding Window
Java
class Solution { public int[] resultsArray(int[] nums, int k) { int n = nums.length; int[] f = new int[n]; Arrays.fill(f, 1); for (int i = 1; i < n; ++i) { if (nums[i] == nums[i - 1] + 1) { f[i] = f[i - 1] + 1; } } int[] ans = new int[n - k + 1]; for (int i = k - 1; i < n; ++i) { ans[i - k + 1] = f[i] >= k ? nums[i] : -1; } return ans; } }
3,255
Find the Power of K-Size Subarrays II
Medium
<p>You are given an array of integers <code>nums</code> of length <code>n</code> and a <em>positive</em> integer <code>k</code>.</p> <p>The <strong>power</strong> of an array is defined as:</p> <ul> <li>Its <strong>maximum</strong> element if <em>all</em> of its elements are <strong>consecutive</strong> and <strong>sorted</strong> in <strong>ascending</strong> order.</li> <li>-1 otherwise.</li> </ul> <p>You need to find the <strong>power</strong> of all <span data-keyword="subarray-nonempty">subarrays</span> of <code>nums</code> of size <code>k</code>.</p> <p>Return an integer array <code>results</code> of size <code>n - k + 1</code>, where <code>results[i]</code> is the <em>power</em> of <code>nums[i..(i + k - 1)]</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,2,3,4,3,2,5], k = 3</span></p> <p><strong>Output:</strong> [3,4,-1,-1,-1]</p> <p><strong>Explanation:</strong></p> <p>There are 5 subarrays of <code>nums</code> of size 3:</p> <ul> <li><code>[1, 2, 3]</code> with the maximum element 3.</li> <li><code>[2, 3, 4]</code> with the maximum element 4.</li> <li><code>[3, 4, 3]</code> whose elements are <strong>not</strong> consecutive.</li> <li><code>[4, 3, 2]</code> whose elements are <strong>not</strong> sorted.</li> <li><code>[3, 2, 5]</code> whose elements are <strong>not</strong> consecutive.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,2,2,2,2], k = 4</span></p> <p><strong>Output:</strong> <span class="example-io">[-1,-1]</span></p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [3,2,3,2,3,2], k = 2</span></p> <p><strong>Output:</strong> <span class="example-io">[-1,3,-1,3,-1]</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == nums.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>6</sup></code></li> <li><code>1 &lt;= k &lt;= n</code></li> </ul>
Array; Sliding Window
Python
class Solution: def resultsArray(self, nums: List[int], k: int) -> List[int]: n = len(nums) f = [1] * n for i in range(1, n): if nums[i] == nums[i - 1] + 1: f[i] = f[i - 1] + 1 return [nums[i] if f[i] >= k else -1 for i in range(k - 1, n)]
3,255
Find the Power of K-Size Subarrays II
Medium
<p>You are given an array of integers <code>nums</code> of length <code>n</code> and a <em>positive</em> integer <code>k</code>.</p> <p>The <strong>power</strong> of an array is defined as:</p> <ul> <li>Its <strong>maximum</strong> element if <em>all</em> of its elements are <strong>consecutive</strong> and <strong>sorted</strong> in <strong>ascending</strong> order.</li> <li>-1 otherwise.</li> </ul> <p>You need to find the <strong>power</strong> of all <span data-keyword="subarray-nonempty">subarrays</span> of <code>nums</code> of size <code>k</code>.</p> <p>Return an integer array <code>results</code> of size <code>n - k + 1</code>, where <code>results[i]</code> is the <em>power</em> of <code>nums[i..(i + k - 1)]</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,2,3,4,3,2,5], k = 3</span></p> <p><strong>Output:</strong> [3,4,-1,-1,-1]</p> <p><strong>Explanation:</strong></p> <p>There are 5 subarrays of <code>nums</code> of size 3:</p> <ul> <li><code>[1, 2, 3]</code> with the maximum element 3.</li> <li><code>[2, 3, 4]</code> with the maximum element 4.</li> <li><code>[3, 4, 3]</code> whose elements are <strong>not</strong> consecutive.</li> <li><code>[4, 3, 2]</code> whose elements are <strong>not</strong> sorted.</li> <li><code>[3, 2, 5]</code> whose elements are <strong>not</strong> consecutive.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,2,2,2,2], k = 4</span></p> <p><strong>Output:</strong> <span class="example-io">[-1,-1]</span></p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [3,2,3,2,3,2], k = 2</span></p> <p><strong>Output:</strong> <span class="example-io">[-1,3,-1,3,-1]</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == nums.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>6</sup></code></li> <li><code>1 &lt;= k &lt;= n</code></li> </ul>
Array; Sliding Window
TypeScript
function resultsArray(nums: number[], k: number): number[] { const n = nums.length; const f: number[] = Array(n).fill(1); for (let i = 1; i < n; ++i) { if (nums[i] === nums[i - 1] + 1) { f[i] = f[i - 1] + 1; } } const ans: number[] = []; for (let i = k - 1; i < n; ++i) { ans.push(f[i] >= k ? nums[i] : -1); } return ans; }
3,258
Count Substrings That Satisfy K-Constraint I
Easy
<p>You are given a <strong>binary</strong> string <code>s</code> and an integer <code>k</code>.</p> <p>A <strong>binary string</strong> satisfies the <strong>k-constraint</strong> if <strong>either</strong> of the following conditions holds:</p> <ul> <li>The number of <code>0</code>&#39;s in the string is at most <code>k</code>.</li> <li>The number of <code>1</code>&#39;s in the string is at most <code>k</code>.</li> </ul> <p>Return an integer denoting the number of <span data-keyword="substring-nonempty">substrings</span> of <code>s</code> that satisfy the <strong>k-constraint</strong>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;10101&quot;, k = 1</span></p> <p><strong>Output:</strong> <span class="example-io">12</span></p> <p><strong>Explanation:</strong></p> <p>Every substring of <code>s</code> except the substrings <code>&quot;1010&quot;</code>, <code>&quot;10101&quot;</code>, and <code>&quot;0101&quot;</code> satisfies the k-constraint.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;1010101&quot;, k = 2</span></p> <p><strong>Output:</strong> <span class="example-io">25</span></p> <p><strong>Explanation:</strong></p> <p>Every substring of <code>s</code> except the substrings with a length greater than 5 satisfies the k-constraint.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;11111&quot;, k = 1</span></p> <p><strong>Output:</strong> <span class="example-io">15</span></p> <p><strong>Explanation:</strong></p> <p>All substrings of <code>s</code> satisfy the k-constraint.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 50 </code></li> <li><code>1 &lt;= k &lt;= s.length</code></li> <li><code>s[i]</code> is either <code>&#39;0&#39;</code> or <code>&#39;1&#39;</code>.</li> </ul>
String; Sliding Window
C++
class Solution { public: int countKConstraintSubstrings(string s, int k) { int cnt[2]{}; int ans = 0, l = 0; for (int r = 0; r < s.length(); ++r) { cnt[s[r] - '0']++; while (cnt[0] > k && cnt[1] > k) { cnt[s[l++] - '0']--; } ans += r - l + 1; } return ans; } };
3,258
Count Substrings That Satisfy K-Constraint I
Easy
<p>You are given a <strong>binary</strong> string <code>s</code> and an integer <code>k</code>.</p> <p>A <strong>binary string</strong> satisfies the <strong>k-constraint</strong> if <strong>either</strong> of the following conditions holds:</p> <ul> <li>The number of <code>0</code>&#39;s in the string is at most <code>k</code>.</li> <li>The number of <code>1</code>&#39;s in the string is at most <code>k</code>.</li> </ul> <p>Return an integer denoting the number of <span data-keyword="substring-nonempty">substrings</span> of <code>s</code> that satisfy the <strong>k-constraint</strong>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;10101&quot;, k = 1</span></p> <p><strong>Output:</strong> <span class="example-io">12</span></p> <p><strong>Explanation:</strong></p> <p>Every substring of <code>s</code> except the substrings <code>&quot;1010&quot;</code>, <code>&quot;10101&quot;</code>, and <code>&quot;0101&quot;</code> satisfies the k-constraint.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;1010101&quot;, k = 2</span></p> <p><strong>Output:</strong> <span class="example-io">25</span></p> <p><strong>Explanation:</strong></p> <p>Every substring of <code>s</code> except the substrings with a length greater than 5 satisfies the k-constraint.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;11111&quot;, k = 1</span></p> <p><strong>Output:</strong> <span class="example-io">15</span></p> <p><strong>Explanation:</strong></p> <p>All substrings of <code>s</code> satisfy the k-constraint.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 50 </code></li> <li><code>1 &lt;= k &lt;= s.length</code></li> <li><code>s[i]</code> is either <code>&#39;0&#39;</code> or <code>&#39;1&#39;</code>.</li> </ul>
String; Sliding Window
Go
func countKConstraintSubstrings(s string, k int) (ans int) { cnt := [2]int{} l := 0 for r, c := range s { cnt[c-'0']++ for ; cnt[0] > k && cnt[1] > k; l++ { cnt[s[l]-'0']-- } ans += r - l + 1 } return }
3,258
Count Substrings That Satisfy K-Constraint I
Easy
<p>You are given a <strong>binary</strong> string <code>s</code> and an integer <code>k</code>.</p> <p>A <strong>binary string</strong> satisfies the <strong>k-constraint</strong> if <strong>either</strong> of the following conditions holds:</p> <ul> <li>The number of <code>0</code>&#39;s in the string is at most <code>k</code>.</li> <li>The number of <code>1</code>&#39;s in the string is at most <code>k</code>.</li> </ul> <p>Return an integer denoting the number of <span data-keyword="substring-nonempty">substrings</span> of <code>s</code> that satisfy the <strong>k-constraint</strong>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;10101&quot;, k = 1</span></p> <p><strong>Output:</strong> <span class="example-io">12</span></p> <p><strong>Explanation:</strong></p> <p>Every substring of <code>s</code> except the substrings <code>&quot;1010&quot;</code>, <code>&quot;10101&quot;</code>, and <code>&quot;0101&quot;</code> satisfies the k-constraint.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;1010101&quot;, k = 2</span></p> <p><strong>Output:</strong> <span class="example-io">25</span></p> <p><strong>Explanation:</strong></p> <p>Every substring of <code>s</code> except the substrings with a length greater than 5 satisfies the k-constraint.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;11111&quot;, k = 1</span></p> <p><strong>Output:</strong> <span class="example-io">15</span></p> <p><strong>Explanation:</strong></p> <p>All substrings of <code>s</code> satisfy the k-constraint.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 50 </code></li> <li><code>1 &lt;= k &lt;= s.length</code></li> <li><code>s[i]</code> is either <code>&#39;0&#39;</code> or <code>&#39;1&#39;</code>.</li> </ul>
String; Sliding Window
Java
class Solution { public int countKConstraintSubstrings(String s, int k) { int[] cnt = new int[2]; int ans = 0, l = 0; for (int r = 0; r < s.length(); ++r) { ++cnt[s.charAt(r) - '0']; while (cnt[0] > k && cnt[1] > k) { cnt[s.charAt(l++) - '0']--; } ans += r - l + 1; } return ans; } }
3,258
Count Substrings That Satisfy K-Constraint I
Easy
<p>You are given a <strong>binary</strong> string <code>s</code> and an integer <code>k</code>.</p> <p>A <strong>binary string</strong> satisfies the <strong>k-constraint</strong> if <strong>either</strong> of the following conditions holds:</p> <ul> <li>The number of <code>0</code>&#39;s in the string is at most <code>k</code>.</li> <li>The number of <code>1</code>&#39;s in the string is at most <code>k</code>.</li> </ul> <p>Return an integer denoting the number of <span data-keyword="substring-nonempty">substrings</span> of <code>s</code> that satisfy the <strong>k-constraint</strong>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;10101&quot;, k = 1</span></p> <p><strong>Output:</strong> <span class="example-io">12</span></p> <p><strong>Explanation:</strong></p> <p>Every substring of <code>s</code> except the substrings <code>&quot;1010&quot;</code>, <code>&quot;10101&quot;</code>, and <code>&quot;0101&quot;</code> satisfies the k-constraint.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;1010101&quot;, k = 2</span></p> <p><strong>Output:</strong> <span class="example-io">25</span></p> <p><strong>Explanation:</strong></p> <p>Every substring of <code>s</code> except the substrings with a length greater than 5 satisfies the k-constraint.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;11111&quot;, k = 1</span></p> <p><strong>Output:</strong> <span class="example-io">15</span></p> <p><strong>Explanation:</strong></p> <p>All substrings of <code>s</code> satisfy the k-constraint.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 50 </code></li> <li><code>1 &lt;= k &lt;= s.length</code></li> <li><code>s[i]</code> is either <code>&#39;0&#39;</code> or <code>&#39;1&#39;</code>.</li> </ul>
String; Sliding Window
Python
class Solution: def countKConstraintSubstrings(self, s: str, k: int) -> int: cnt = [0, 0] ans = l = 0 for r, x in enumerate(map(int, s)): cnt[x] += 1 while cnt[0] > k and cnt[1] > k: cnt[int(s[l])] -= 1 l += 1 ans += r - l + 1 return ans
3,258
Count Substrings That Satisfy K-Constraint I
Easy
<p>You are given a <strong>binary</strong> string <code>s</code> and an integer <code>k</code>.</p> <p>A <strong>binary string</strong> satisfies the <strong>k-constraint</strong> if <strong>either</strong> of the following conditions holds:</p> <ul> <li>The number of <code>0</code>&#39;s in the string is at most <code>k</code>.</li> <li>The number of <code>1</code>&#39;s in the string is at most <code>k</code>.</li> </ul> <p>Return an integer denoting the number of <span data-keyword="substring-nonempty">substrings</span> of <code>s</code> that satisfy the <strong>k-constraint</strong>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;10101&quot;, k = 1</span></p> <p><strong>Output:</strong> <span class="example-io">12</span></p> <p><strong>Explanation:</strong></p> <p>Every substring of <code>s</code> except the substrings <code>&quot;1010&quot;</code>, <code>&quot;10101&quot;</code>, and <code>&quot;0101&quot;</code> satisfies the k-constraint.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;1010101&quot;, k = 2</span></p> <p><strong>Output:</strong> <span class="example-io">25</span></p> <p><strong>Explanation:</strong></p> <p>Every substring of <code>s</code> except the substrings with a length greater than 5 satisfies the k-constraint.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;11111&quot;, k = 1</span></p> <p><strong>Output:</strong> <span class="example-io">15</span></p> <p><strong>Explanation:</strong></p> <p>All substrings of <code>s</code> satisfy the k-constraint.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 50 </code></li> <li><code>1 &lt;= k &lt;= s.length</code></li> <li><code>s[i]</code> is either <code>&#39;0&#39;</code> or <code>&#39;1&#39;</code>.</li> </ul>
String; Sliding Window
Rust
impl Solution { pub fn count_k_constraint_substrings(s: String, k: i32) -> i32 { let mut cnt = [0; 2]; let mut l = 0; let mut ans = 0; let s = s.as_bytes(); for (r, &c) in s.iter().enumerate() { cnt[(c - b'0') as usize] += 1; while cnt[0] > k && cnt[1] > k { cnt[(s[l] - b'0') as usize] -= 1; l += 1; } ans += r - l + 1; } ans as i32 } }
3,258
Count Substrings That Satisfy K-Constraint I
Easy
<p>You are given a <strong>binary</strong> string <code>s</code> and an integer <code>k</code>.</p> <p>A <strong>binary string</strong> satisfies the <strong>k-constraint</strong> if <strong>either</strong> of the following conditions holds:</p> <ul> <li>The number of <code>0</code>&#39;s in the string is at most <code>k</code>.</li> <li>The number of <code>1</code>&#39;s in the string is at most <code>k</code>.</li> </ul> <p>Return an integer denoting the number of <span data-keyword="substring-nonempty">substrings</span> of <code>s</code> that satisfy the <strong>k-constraint</strong>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;10101&quot;, k = 1</span></p> <p><strong>Output:</strong> <span class="example-io">12</span></p> <p><strong>Explanation:</strong></p> <p>Every substring of <code>s</code> except the substrings <code>&quot;1010&quot;</code>, <code>&quot;10101&quot;</code>, and <code>&quot;0101&quot;</code> satisfies the k-constraint.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;1010101&quot;, k = 2</span></p> <p><strong>Output:</strong> <span class="example-io">25</span></p> <p><strong>Explanation:</strong></p> <p>Every substring of <code>s</code> except the substrings with a length greater than 5 satisfies the k-constraint.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;11111&quot;, k = 1</span></p> <p><strong>Output:</strong> <span class="example-io">15</span></p> <p><strong>Explanation:</strong></p> <p>All substrings of <code>s</code> satisfy the k-constraint.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 50 </code></li> <li><code>1 &lt;= k &lt;= s.length</code></li> <li><code>s[i]</code> is either <code>&#39;0&#39;</code> or <code>&#39;1&#39;</code>.</li> </ul>
String; Sliding Window
TypeScript
function countKConstraintSubstrings(s: string, k: number): number { const cnt: [number, number] = [0, 0]; let [ans, l] = [0, 0]; for (let r = 0; r < s.length; ++r) { cnt[+s[r]]++; while (cnt[0] > k && cnt[1] > k) { cnt[+s[l++]]--; } ans += r - l + 1; } return ans; }
3,259
Maximum Energy Boost From Two Drinks
Medium
<p>You are given two integer arrays <code>energyDrinkA</code> and <code>energyDrinkB</code> of the same length <code>n</code> by a futuristic sports scientist. These arrays represent the energy boosts per hour provided by two different energy drinks, A and B, respectively.</p> <p>You want to <em>maximize</em> your total energy boost by drinking one energy drink <em>per hour</em>. However, if you want to switch from consuming one energy drink to the other, you need to wait for <em>one hour</em> to cleanse your system (meaning you won&#39;t get any energy boost in that hour).</p> <p>Return the <strong>maximum</strong> total energy boost you can gain in the next <code>n</code> hours.</p> <p><strong>Note</strong> that you can start consuming <em>either</em> of the two energy drinks.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> energyDrinkA<span class="example-io"> = [1,3,1], </span>energyDrinkB<span class="example-io"> = [3,1,1]</span></p> <p><strong>Output:</strong> <span class="example-io">5</span></p> <p><strong>Explanation:</strong></p> <p>To gain an energy boost of 5, drink only the energy drink A (or only B).</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> energyDrinkA<span class="example-io"> = [4,1,1], </span>energyDrinkB<span class="example-io"> = [1,1,3]</span></p> <p><strong>Output:</strong> <span class="example-io">7</span></p> <p><strong>Explanation:</strong></p> <p>To gain an energy boost of 7:</p> <ul> <li>Drink the energy drink A for the first hour.</li> <li>Switch to the energy drink B and we lose the energy boost of the second hour.</li> <li>Gain the energy boost of the drink B in the third hour.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>n == energyDrinkA.length == energyDrinkB.length</code></li> <li><code>3 &lt;= n &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= energyDrinkA[i], energyDrinkB[i] &lt;= 10<sup>5</sup></code></li> </ul>
Array; Dynamic Programming
C++
class Solution { public: long long maxEnergyBoost(vector<int>& energyDrinkA, vector<int>& energyDrinkB) { int n = energyDrinkA.size(); vector<vector<long long>> f(n, vector<long long>(2)); f[0][0] = energyDrinkA[0]; f[0][1] = energyDrinkB[0]; for (int i = 1; i < n; ++i) { f[i][0] = max(f[i - 1][0] + energyDrinkA[i], f[i - 1][1]); f[i][1] = max(f[i - 1][1] + energyDrinkB[i], f[i - 1][0]); } return max(f[n - 1][0], f[n - 1][1]); } };
3,259
Maximum Energy Boost From Two Drinks
Medium
<p>You are given two integer arrays <code>energyDrinkA</code> and <code>energyDrinkB</code> of the same length <code>n</code> by a futuristic sports scientist. These arrays represent the energy boosts per hour provided by two different energy drinks, A and B, respectively.</p> <p>You want to <em>maximize</em> your total energy boost by drinking one energy drink <em>per hour</em>. However, if you want to switch from consuming one energy drink to the other, you need to wait for <em>one hour</em> to cleanse your system (meaning you won&#39;t get any energy boost in that hour).</p> <p>Return the <strong>maximum</strong> total energy boost you can gain in the next <code>n</code> hours.</p> <p><strong>Note</strong> that you can start consuming <em>either</em> of the two energy drinks.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> energyDrinkA<span class="example-io"> = [1,3,1], </span>energyDrinkB<span class="example-io"> = [3,1,1]</span></p> <p><strong>Output:</strong> <span class="example-io">5</span></p> <p><strong>Explanation:</strong></p> <p>To gain an energy boost of 5, drink only the energy drink A (or only B).</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> energyDrinkA<span class="example-io"> = [4,1,1], </span>energyDrinkB<span class="example-io"> = [1,1,3]</span></p> <p><strong>Output:</strong> <span class="example-io">7</span></p> <p><strong>Explanation:</strong></p> <p>To gain an energy boost of 7:</p> <ul> <li>Drink the energy drink A for the first hour.</li> <li>Switch to the energy drink B and we lose the energy boost of the second hour.</li> <li>Gain the energy boost of the drink B in the third hour.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>n == energyDrinkA.length == energyDrinkB.length</code></li> <li><code>3 &lt;= n &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= energyDrinkA[i], energyDrinkB[i] &lt;= 10<sup>5</sup></code></li> </ul>
Array; Dynamic Programming
Go
func maxEnergyBoost(energyDrinkA []int, energyDrinkB []int) int64 { n := len(energyDrinkA) f := make([][2]int64, n) f[0][0] = int64(energyDrinkA[0]) f[0][1] = int64(energyDrinkB[0]) for i := 1; i < n; i++ { f[i][0] = max(f[i-1][0]+int64(energyDrinkA[i]), f[i-1][1]) f[i][1] = max(f[i-1][1]+int64(energyDrinkB[i]), f[i-1][0]) } return max(f[n-1][0], f[n-1][1]) }
3,259
Maximum Energy Boost From Two Drinks
Medium
<p>You are given two integer arrays <code>energyDrinkA</code> and <code>energyDrinkB</code> of the same length <code>n</code> by a futuristic sports scientist. These arrays represent the energy boosts per hour provided by two different energy drinks, A and B, respectively.</p> <p>You want to <em>maximize</em> your total energy boost by drinking one energy drink <em>per hour</em>. However, if you want to switch from consuming one energy drink to the other, you need to wait for <em>one hour</em> to cleanse your system (meaning you won&#39;t get any energy boost in that hour).</p> <p>Return the <strong>maximum</strong> total energy boost you can gain in the next <code>n</code> hours.</p> <p><strong>Note</strong> that you can start consuming <em>either</em> of the two energy drinks.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> energyDrinkA<span class="example-io"> = [1,3,1], </span>energyDrinkB<span class="example-io"> = [3,1,1]</span></p> <p><strong>Output:</strong> <span class="example-io">5</span></p> <p><strong>Explanation:</strong></p> <p>To gain an energy boost of 5, drink only the energy drink A (or only B).</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> energyDrinkA<span class="example-io"> = [4,1,1], </span>energyDrinkB<span class="example-io"> = [1,1,3]</span></p> <p><strong>Output:</strong> <span class="example-io">7</span></p> <p><strong>Explanation:</strong></p> <p>To gain an energy boost of 7:</p> <ul> <li>Drink the energy drink A for the first hour.</li> <li>Switch to the energy drink B and we lose the energy boost of the second hour.</li> <li>Gain the energy boost of the drink B in the third hour.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>n == energyDrinkA.length == energyDrinkB.length</code></li> <li><code>3 &lt;= n &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= energyDrinkA[i], energyDrinkB[i] &lt;= 10<sup>5</sup></code></li> </ul>
Array; Dynamic Programming
Java
class Solution { public long maxEnergyBoost(int[] energyDrinkA, int[] energyDrinkB) { int n = energyDrinkA.length; long[][] f = new long[n][2]; f[0][0] = energyDrinkA[0]; f[0][1] = energyDrinkB[0]; for (int i = 1; i < n; ++i) { f[i][0] = Math.max(f[i - 1][0] + energyDrinkA[i], f[i - 1][1]); f[i][1] = Math.max(f[i - 1][1] + energyDrinkB[i], f[i - 1][0]); } return Math.max(f[n - 1][0], f[n - 1][1]); } }
3,259
Maximum Energy Boost From Two Drinks
Medium
<p>You are given two integer arrays <code>energyDrinkA</code> and <code>energyDrinkB</code> of the same length <code>n</code> by a futuristic sports scientist. These arrays represent the energy boosts per hour provided by two different energy drinks, A and B, respectively.</p> <p>You want to <em>maximize</em> your total energy boost by drinking one energy drink <em>per hour</em>. However, if you want to switch from consuming one energy drink to the other, you need to wait for <em>one hour</em> to cleanse your system (meaning you won&#39;t get any energy boost in that hour).</p> <p>Return the <strong>maximum</strong> total energy boost you can gain in the next <code>n</code> hours.</p> <p><strong>Note</strong> that you can start consuming <em>either</em> of the two energy drinks.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> energyDrinkA<span class="example-io"> = [1,3,1], </span>energyDrinkB<span class="example-io"> = [3,1,1]</span></p> <p><strong>Output:</strong> <span class="example-io">5</span></p> <p><strong>Explanation:</strong></p> <p>To gain an energy boost of 5, drink only the energy drink A (or only B).</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> energyDrinkA<span class="example-io"> = [4,1,1], </span>energyDrinkB<span class="example-io"> = [1,1,3]</span></p> <p><strong>Output:</strong> <span class="example-io">7</span></p> <p><strong>Explanation:</strong></p> <p>To gain an energy boost of 7:</p> <ul> <li>Drink the energy drink A for the first hour.</li> <li>Switch to the energy drink B and we lose the energy boost of the second hour.</li> <li>Gain the energy boost of the drink B in the third hour.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>n == energyDrinkA.length == energyDrinkB.length</code></li> <li><code>3 &lt;= n &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= energyDrinkA[i], energyDrinkB[i] &lt;= 10<sup>5</sup></code></li> </ul>
Array; Dynamic Programming
Python
class Solution: def maxEnergyBoost(self, energyDrinkA: List[int], energyDrinkB: List[int]) -> int: n = len(energyDrinkA) f = [[0] * 2 for _ in range(n)] f[0][0] = energyDrinkA[0] f[0][1] = energyDrinkB[0] for i in range(1, n): f[i][0] = max(f[i - 1][0] + energyDrinkA[i], f[i - 1][1]) f[i][1] = max(f[i - 1][1] + energyDrinkB[i], f[i - 1][0]) return max(f[n - 1])
3,259
Maximum Energy Boost From Two Drinks
Medium
<p>You are given two integer arrays <code>energyDrinkA</code> and <code>energyDrinkB</code> of the same length <code>n</code> by a futuristic sports scientist. These arrays represent the energy boosts per hour provided by two different energy drinks, A and B, respectively.</p> <p>You want to <em>maximize</em> your total energy boost by drinking one energy drink <em>per hour</em>. However, if you want to switch from consuming one energy drink to the other, you need to wait for <em>one hour</em> to cleanse your system (meaning you won&#39;t get any energy boost in that hour).</p> <p>Return the <strong>maximum</strong> total energy boost you can gain in the next <code>n</code> hours.</p> <p><strong>Note</strong> that you can start consuming <em>either</em> of the two energy drinks.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> energyDrinkA<span class="example-io"> = [1,3,1], </span>energyDrinkB<span class="example-io"> = [3,1,1]</span></p> <p><strong>Output:</strong> <span class="example-io">5</span></p> <p><strong>Explanation:</strong></p> <p>To gain an energy boost of 5, drink only the energy drink A (or only B).</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> energyDrinkA<span class="example-io"> = [4,1,1], </span>energyDrinkB<span class="example-io"> = [1,1,3]</span></p> <p><strong>Output:</strong> <span class="example-io">7</span></p> <p><strong>Explanation:</strong></p> <p>To gain an energy boost of 7:</p> <ul> <li>Drink the energy drink A for the first hour.</li> <li>Switch to the energy drink B and we lose the energy boost of the second hour.</li> <li>Gain the energy boost of the drink B in the third hour.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>n == energyDrinkA.length == energyDrinkB.length</code></li> <li><code>3 &lt;= n &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= energyDrinkA[i], energyDrinkB[i] &lt;= 10<sup>5</sup></code></li> </ul>
Array; Dynamic Programming
TypeScript
function maxEnergyBoost(energyDrinkA: number[], energyDrinkB: number[]): number { const n = energyDrinkA.length; const f: number[][] = Array.from({ length: n }, () => [0, 0]); f[0][0] = energyDrinkA[0]; f[0][1] = energyDrinkB[0]; for (let i = 1; i < n; i++) { f[i][0] = Math.max(f[i - 1][0] + energyDrinkA[i], f[i - 1][1]); f[i][1] = Math.max(f[i - 1][1] + energyDrinkB[i], f[i - 1][0]); } return Math.max(...f[n - 1]!); }
3,261
Count Substrings That Satisfy K-Constraint II
Hard
<p>You are given a <strong>binary</strong> string <code>s</code> and an integer <code>k</code>.</p> <p>You are also given a 2D integer array <code>queries</code>, where <code>queries[i] = [l<sub>i</sub>, r<sub>i</sub>]</code>.</p> <p>A <strong>binary string</strong> satisfies the <strong>k-constraint</strong> if <strong>either</strong> of the following conditions holds:</p> <ul> <li>The number of <code>0</code>&#39;s in the string is at most <code>k</code>.</li> <li>The number of <code>1</code>&#39;s in the string is at most <code>k</code>.</li> </ul> <p>Return an integer array <code>answer</code>, where <code>answer[i]</code> is the number of <span data-keyword="substring-nonempty">substrings</span> of <code>s[l<sub>i</sub>..r<sub>i</sub>]</code> that satisfy the <strong>k-constraint</strong>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;0001111&quot;, k = 2, queries = [[0,6]]</span></p> <p><strong>Output:</strong> <span class="example-io">[26]</span></p> <p><strong>Explanation:</strong></p> <p>For the query <code>[0, 6]</code>, all substrings of <code>s[0..6] = &quot;0001111&quot;</code> satisfy the k-constraint except for the substrings <code>s[0..5] = &quot;000111&quot;</code> and <code>s[0..6] = &quot;0001111&quot;</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;010101&quot;, k = 1, queries = [[0,5],[1,4],[2,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">[15,9,3]</span></p> <p><strong>Explanation:</strong></p> <p>The substrings of <code>s</code> with a length greater than 3 do not satisfy the k-constraint.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 10<sup>5</sup></code></li> <li><code>s[i]</code> is either <code>&#39;0&#39;</code> or <code>&#39;1&#39;</code>.</li> <li><code>1 &lt;= k &lt;= s.length</code></li> <li><code>1 &lt;= queries.length &lt;= 10<sup>5</sup></code></li> <li><code>queries[i] == [l<sub>i</sub>, r<sub>i</sub>]</code></li> <li><code>0 &lt;= l<sub>i</sub> &lt;= r<sub>i</sub> &lt; s.length</code></li> <li>All queries are distinct.</li> </ul>
Array; String; Binary Search; Prefix Sum; Sliding Window
C++
class Solution { public: vector<long long> countKConstraintSubstrings(string s, int k, vector<vector<int>>& queries) { int cnt[2]{}; int n = s.size(); vector<int> d(n, n); long long pre[n + 1]; pre[0] = 0; for (int i = 0, j = 0; j < n; ++j) { cnt[s[j] - '0']++; while (cnt[0] > k && cnt[1] > k) { d[i] = j; cnt[s[i++] - '0']--; } pre[j + 1] = pre[j] + j - i + 1; } vector<long long> ans; for (const auto& q : queries) { int l = q[0], r = q[1]; int p = min(r + 1, d[l]); long long a = (1LL + p - l) * (p - l) / 2; long long b = pre[r + 1] - pre[p]; ans.push_back(a + b); } return ans; } };
3,261
Count Substrings That Satisfy K-Constraint II
Hard
<p>You are given a <strong>binary</strong> string <code>s</code> and an integer <code>k</code>.</p> <p>You are also given a 2D integer array <code>queries</code>, where <code>queries[i] = [l<sub>i</sub>, r<sub>i</sub>]</code>.</p> <p>A <strong>binary string</strong> satisfies the <strong>k-constraint</strong> if <strong>either</strong> of the following conditions holds:</p> <ul> <li>The number of <code>0</code>&#39;s in the string is at most <code>k</code>.</li> <li>The number of <code>1</code>&#39;s in the string is at most <code>k</code>.</li> </ul> <p>Return an integer array <code>answer</code>, where <code>answer[i]</code> is the number of <span data-keyword="substring-nonempty">substrings</span> of <code>s[l<sub>i</sub>..r<sub>i</sub>]</code> that satisfy the <strong>k-constraint</strong>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;0001111&quot;, k = 2, queries = [[0,6]]</span></p> <p><strong>Output:</strong> <span class="example-io">[26]</span></p> <p><strong>Explanation:</strong></p> <p>For the query <code>[0, 6]</code>, all substrings of <code>s[0..6] = &quot;0001111&quot;</code> satisfy the k-constraint except for the substrings <code>s[0..5] = &quot;000111&quot;</code> and <code>s[0..6] = &quot;0001111&quot;</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;010101&quot;, k = 1, queries = [[0,5],[1,4],[2,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">[15,9,3]</span></p> <p><strong>Explanation:</strong></p> <p>The substrings of <code>s</code> with a length greater than 3 do not satisfy the k-constraint.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 10<sup>5</sup></code></li> <li><code>s[i]</code> is either <code>&#39;0&#39;</code> or <code>&#39;1&#39;</code>.</li> <li><code>1 &lt;= k &lt;= s.length</code></li> <li><code>1 &lt;= queries.length &lt;= 10<sup>5</sup></code></li> <li><code>queries[i] == [l<sub>i</sub>, r<sub>i</sub>]</code></li> <li><code>0 &lt;= l<sub>i</sub> &lt;= r<sub>i</sub> &lt; s.length</code></li> <li>All queries are distinct.</li> </ul>
Array; String; Binary Search; Prefix Sum; Sliding Window
Go
func countKConstraintSubstrings(s string, k int, queries [][]int) (ans []int64) { cnt := [2]int{} n := len(s) d := make([]int, n) for i := range d { d[i] = n } pre := make([]int, n+1) for i, j := 0, 0; j < n; j++ { cnt[s[j]-'0']++ for cnt[0] > k && cnt[1] > k { d[i] = j cnt[s[i]-'0']-- i++ } pre[j+1] = pre[j] + j - i + 1 } for _, q := range queries { l, r := q[0], q[1] p := min(r+1, d[l]) a := (1 + p - l) * (p - l) / 2 b := pre[r+1] - pre[p] ans = append(ans, int64(a+b)) } return }
3,261
Count Substrings That Satisfy K-Constraint II
Hard
<p>You are given a <strong>binary</strong> string <code>s</code> and an integer <code>k</code>.</p> <p>You are also given a 2D integer array <code>queries</code>, where <code>queries[i] = [l<sub>i</sub>, r<sub>i</sub>]</code>.</p> <p>A <strong>binary string</strong> satisfies the <strong>k-constraint</strong> if <strong>either</strong> of the following conditions holds:</p> <ul> <li>The number of <code>0</code>&#39;s in the string is at most <code>k</code>.</li> <li>The number of <code>1</code>&#39;s in the string is at most <code>k</code>.</li> </ul> <p>Return an integer array <code>answer</code>, where <code>answer[i]</code> is the number of <span data-keyword="substring-nonempty">substrings</span> of <code>s[l<sub>i</sub>..r<sub>i</sub>]</code> that satisfy the <strong>k-constraint</strong>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;0001111&quot;, k = 2, queries = [[0,6]]</span></p> <p><strong>Output:</strong> <span class="example-io">[26]</span></p> <p><strong>Explanation:</strong></p> <p>For the query <code>[0, 6]</code>, all substrings of <code>s[0..6] = &quot;0001111&quot;</code> satisfy the k-constraint except for the substrings <code>s[0..5] = &quot;000111&quot;</code> and <code>s[0..6] = &quot;0001111&quot;</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;010101&quot;, k = 1, queries = [[0,5],[1,4],[2,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">[15,9,3]</span></p> <p><strong>Explanation:</strong></p> <p>The substrings of <code>s</code> with a length greater than 3 do not satisfy the k-constraint.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 10<sup>5</sup></code></li> <li><code>s[i]</code> is either <code>&#39;0&#39;</code> or <code>&#39;1&#39;</code>.</li> <li><code>1 &lt;= k &lt;= s.length</code></li> <li><code>1 &lt;= queries.length &lt;= 10<sup>5</sup></code></li> <li><code>queries[i] == [l<sub>i</sub>, r<sub>i</sub>]</code></li> <li><code>0 &lt;= l<sub>i</sub> &lt;= r<sub>i</sub> &lt; s.length</code></li> <li>All queries are distinct.</li> </ul>
Array; String; Binary Search; Prefix Sum; Sliding Window
Java
class Solution { public long[] countKConstraintSubstrings(String s, int k, int[][] queries) { int[] cnt = new int[2]; int n = s.length(); int[] d = new int[n]; Arrays.fill(d, n); long[] pre = new long[n + 1]; for (int i = 0, j = 0; j < n; ++j) { cnt[s.charAt(j) - '0']++; while (cnt[0] > k && cnt[1] > k) { d[i] = j; cnt[s.charAt(i++) - '0']--; } pre[j + 1] = pre[j] + j - i + 1; } int m = queries.length; long[] ans = new long[m]; for (int i = 0; i < m; ++i) { int l = queries[i][0], r = queries[i][1]; int p = Math.min(r + 1, d[l]); long a = (1L + p - l) * (p - l) / 2; long b = pre[r + 1] - pre[p]; ans[i] = a + b; } return ans; } }
3,261
Count Substrings That Satisfy K-Constraint II
Hard
<p>You are given a <strong>binary</strong> string <code>s</code> and an integer <code>k</code>.</p> <p>You are also given a 2D integer array <code>queries</code>, where <code>queries[i] = [l<sub>i</sub>, r<sub>i</sub>]</code>.</p> <p>A <strong>binary string</strong> satisfies the <strong>k-constraint</strong> if <strong>either</strong> of the following conditions holds:</p> <ul> <li>The number of <code>0</code>&#39;s in the string is at most <code>k</code>.</li> <li>The number of <code>1</code>&#39;s in the string is at most <code>k</code>.</li> </ul> <p>Return an integer array <code>answer</code>, where <code>answer[i]</code> is the number of <span data-keyword="substring-nonempty">substrings</span> of <code>s[l<sub>i</sub>..r<sub>i</sub>]</code> that satisfy the <strong>k-constraint</strong>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;0001111&quot;, k = 2, queries = [[0,6]]</span></p> <p><strong>Output:</strong> <span class="example-io">[26]</span></p> <p><strong>Explanation:</strong></p> <p>For the query <code>[0, 6]</code>, all substrings of <code>s[0..6] = &quot;0001111&quot;</code> satisfy the k-constraint except for the substrings <code>s[0..5] = &quot;000111&quot;</code> and <code>s[0..6] = &quot;0001111&quot;</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;010101&quot;, k = 1, queries = [[0,5],[1,4],[2,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">[15,9,3]</span></p> <p><strong>Explanation:</strong></p> <p>The substrings of <code>s</code> with a length greater than 3 do not satisfy the k-constraint.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 10<sup>5</sup></code></li> <li><code>s[i]</code> is either <code>&#39;0&#39;</code> or <code>&#39;1&#39;</code>.</li> <li><code>1 &lt;= k &lt;= s.length</code></li> <li><code>1 &lt;= queries.length &lt;= 10<sup>5</sup></code></li> <li><code>queries[i] == [l<sub>i</sub>, r<sub>i</sub>]</code></li> <li><code>0 &lt;= l<sub>i</sub> &lt;= r<sub>i</sub> &lt; s.length</code></li> <li>All queries are distinct.</li> </ul>
Array; String; Binary Search; Prefix Sum; Sliding Window
Python
class Solution: def countKConstraintSubstrings( self, s: str, k: int, queries: List[List[int]] ) -> List[int]: cnt = [0, 0] i, n = 0, len(s) d = [n] * n pre = [0] * (n + 1) for j, x in enumerate(map(int, s)): cnt[x] += 1 while cnt[0] > k and cnt[1] > k: d[i] = j cnt[int(s[i])] -= 1 i += 1 pre[j + 1] = pre[j] + j - i + 1 ans = [] for l, r in queries: p = min(r + 1, d[l]) a = (1 + p - l) * (p - l) // 2 b = pre[r + 1] - pre[p] ans.append(a + b) return ans
3,261
Count Substrings That Satisfy K-Constraint II
Hard
<p>You are given a <strong>binary</strong> string <code>s</code> and an integer <code>k</code>.</p> <p>You are also given a 2D integer array <code>queries</code>, where <code>queries[i] = [l<sub>i</sub>, r<sub>i</sub>]</code>.</p> <p>A <strong>binary string</strong> satisfies the <strong>k-constraint</strong> if <strong>either</strong> of the following conditions holds:</p> <ul> <li>The number of <code>0</code>&#39;s in the string is at most <code>k</code>.</li> <li>The number of <code>1</code>&#39;s in the string is at most <code>k</code>.</li> </ul> <p>Return an integer array <code>answer</code>, where <code>answer[i]</code> is the number of <span data-keyword="substring-nonempty">substrings</span> of <code>s[l<sub>i</sub>..r<sub>i</sub>]</code> that satisfy the <strong>k-constraint</strong>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;0001111&quot;, k = 2, queries = [[0,6]]</span></p> <p><strong>Output:</strong> <span class="example-io">[26]</span></p> <p><strong>Explanation:</strong></p> <p>For the query <code>[0, 6]</code>, all substrings of <code>s[0..6] = &quot;0001111&quot;</code> satisfy the k-constraint except for the substrings <code>s[0..5] = &quot;000111&quot;</code> and <code>s[0..6] = &quot;0001111&quot;</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;010101&quot;, k = 1, queries = [[0,5],[1,4],[2,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">[15,9,3]</span></p> <p><strong>Explanation:</strong></p> <p>The substrings of <code>s</code> with a length greater than 3 do not satisfy the k-constraint.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 10<sup>5</sup></code></li> <li><code>s[i]</code> is either <code>&#39;0&#39;</code> or <code>&#39;1&#39;</code>.</li> <li><code>1 &lt;= k &lt;= s.length</code></li> <li><code>1 &lt;= queries.length &lt;= 10<sup>5</sup></code></li> <li><code>queries[i] == [l<sub>i</sub>, r<sub>i</sub>]</code></li> <li><code>0 &lt;= l<sub>i</sub> &lt;= r<sub>i</sub> &lt; s.length</code></li> <li>All queries are distinct.</li> </ul>
Array; String; Binary Search; Prefix Sum; Sliding Window
TypeScript
function countKConstraintSubstrings(s: string, k: number, queries: number[][]): number[] { const cnt: [number, number] = [0, 0]; const n = s.length; const d: number[] = Array(n).fill(n); const pre: number[] = Array(n + 1).fill(0); for (let i = 0, j = 0; j < n; ++j) { cnt[+s[j]]++; while (Math.min(cnt[0], cnt[1]) > k) { d[i] = j; cnt[+s[i++]]--; } pre[j + 1] = pre[j] + j - i + 1; } const ans: number[] = []; for (const [l, r] of queries) { const p = Math.min(r + 1, d[l]); const a = ((1 + p - l) * (p - l)) / 2; const b = pre[r + 1] - pre[p]; ans.push(a + b); } return ans; }
3,262
Find Overlapping Shifts
Medium
<p>Table: <code>EmployeeShifts</code></p> <pre> +------------------+---------+ | Column Name | Type | +------------------+---------+ | employee_id | int | | start_time | time | | end_time | time | +------------------+---------+ (employee_id, start_time) is the unique key for this table. This table contains information about the shifts worked by employees, including the start and end times on a specific date. </pre> <p>Write a solution to count the number of <strong>overlapping shifts</strong> for each employee. Two shifts are considered overlapping if one shift&rsquo;s <code>end_time</code> is <strong>later than</strong> another shift&rsquo;s <code>start_time</code>.</p> <p><em>Return the result table ordered by</em> <code>employee_id</code> <em>in <strong>ascending</strong> order</em>.</p> <p>The query result format is in the following example.</p> <p>&nbsp;</p> <p><strong class="example">Example:</strong></p> <div class="example-block"> <p><strong>Input:</strong></p> <p><code>EmployeeShifts</code> table:</p> <pre class="example-io"> +-------------+------------+----------+ | employee_id | start_time | end_time | +-------------+------------+----------+ | 1 | 08:00:00 | 12:00:00 | | 1 | 11:00:00 | 15:00:00 | | 1 | 14:00:00 | 18:00:00 | | 2 | 09:00:00 | 17:00:00 | | 2 | 16:00:00 | 20:00:00 | | 3 | 10:00:00 | 12:00:00 | | 3 | 13:00:00 | 15:00:00 | | 3 | 16:00:00 | 18:00:00 | | 4 | 08:00:00 | 10:00:00 | | 4 | 09:00:00 | 11:00:00 | +-------------+------------+----------+ </pre> <p><strong>Output:</strong></p> <pre class="example-io"> +-------------+--------------------+ | employee_id | overlapping_shifts | +-------------+--------------------+ | 1 | 2 | | 2 | 1 | | 4 | 1 | +-------------+--------------------+ </pre> <p><strong>Explanation:</strong></p> <ul> <li>Employee 1 has 3 shifts: <ul> <li>08:00:00 to 12:00:00</li> <li>11:00:00 to 15:00:00</li> <li>14:00:00 to 18:00:00</li> </ul> The first shift overlaps with the second, and the second overlaps with the third, resulting in 2 overlapping shifts.</li> <li>Employee 2 has 2 shifts: <ul> <li>09:00:00 to 17:00:00</li> <li>16:00:00 to 20:00:00</li> </ul> These shifts overlap with each other, resulting in 1 overlapping shift.</li> <li>Employee 3 has 3 shifts: <ul> <li>10:00:00 to 12:00:00</li> <li>13:00:00 to 15:00:00</li> <li>16:00:00 to 18:00:00</li> </ul> None of these shifts overlap, so Employee 3 is not included in the output.</li> <li>Employee 4 has 2 shifts: <ul> <li>08:00:00 to 10:00:00</li> <li>09:00:00 to 11:00:00</li> </ul> These shifts overlap with each other, resulting in 1 overlapping shift.</li> </ul> <p>The output shows the employee_id and the count of overlapping shifts for each employee who has at least one overlapping shift, ordered by employee_id in ascending order.</p> </div>
Database
Python
import pandas as pd def find_overlapping_shifts(employee_shifts: pd.DataFrame) -> pd.DataFrame: merged_shifts = employee_shifts.merge( employee_shifts, on="employee_id", suffixes=("_t1", "_t2") ) overlapping_shifts = merged_shifts[ (merged_shifts["start_time_t1"] < merged_shifts["start_time_t2"]) & (merged_shifts["end_time_t1"] > merged_shifts["start_time_t2"]) ] result = ( overlapping_shifts.groupby("employee_id") .size() .reset_index(name="overlapping_shifts") ) result = result[result["overlapping_shifts"] > 0] result = result.sort_values("employee_id").reset_index(drop=True) return result
3,262
Find Overlapping Shifts
Medium
<p>Table: <code>EmployeeShifts</code></p> <pre> +------------------+---------+ | Column Name | Type | +------------------+---------+ | employee_id | int | | start_time | time | | end_time | time | +------------------+---------+ (employee_id, start_time) is the unique key for this table. This table contains information about the shifts worked by employees, including the start and end times on a specific date. </pre> <p>Write a solution to count the number of <strong>overlapping shifts</strong> for each employee. Two shifts are considered overlapping if one shift&rsquo;s <code>end_time</code> is <strong>later than</strong> another shift&rsquo;s <code>start_time</code>.</p> <p><em>Return the result table ordered by</em> <code>employee_id</code> <em>in <strong>ascending</strong> order</em>.</p> <p>The query result format is in the following example.</p> <p>&nbsp;</p> <p><strong class="example">Example:</strong></p> <div class="example-block"> <p><strong>Input:</strong></p> <p><code>EmployeeShifts</code> table:</p> <pre class="example-io"> +-------------+------------+----------+ | employee_id | start_time | end_time | +-------------+------------+----------+ | 1 | 08:00:00 | 12:00:00 | | 1 | 11:00:00 | 15:00:00 | | 1 | 14:00:00 | 18:00:00 | | 2 | 09:00:00 | 17:00:00 | | 2 | 16:00:00 | 20:00:00 | | 3 | 10:00:00 | 12:00:00 | | 3 | 13:00:00 | 15:00:00 | | 3 | 16:00:00 | 18:00:00 | | 4 | 08:00:00 | 10:00:00 | | 4 | 09:00:00 | 11:00:00 | +-------------+------------+----------+ </pre> <p><strong>Output:</strong></p> <pre class="example-io"> +-------------+--------------------+ | employee_id | overlapping_shifts | +-------------+--------------------+ | 1 | 2 | | 2 | 1 | | 4 | 1 | +-------------+--------------------+ </pre> <p><strong>Explanation:</strong></p> <ul> <li>Employee 1 has 3 shifts: <ul> <li>08:00:00 to 12:00:00</li> <li>11:00:00 to 15:00:00</li> <li>14:00:00 to 18:00:00</li> </ul> The first shift overlaps with the second, and the second overlaps with the third, resulting in 2 overlapping shifts.</li> <li>Employee 2 has 2 shifts: <ul> <li>09:00:00 to 17:00:00</li> <li>16:00:00 to 20:00:00</li> </ul> These shifts overlap with each other, resulting in 1 overlapping shift.</li> <li>Employee 3 has 3 shifts: <ul> <li>10:00:00 to 12:00:00</li> <li>13:00:00 to 15:00:00</li> <li>16:00:00 to 18:00:00</li> </ul> None of these shifts overlap, so Employee 3 is not included in the output.</li> <li>Employee 4 has 2 shifts: <ul> <li>08:00:00 to 10:00:00</li> <li>09:00:00 to 11:00:00</li> </ul> These shifts overlap with each other, resulting in 1 overlapping shift.</li> </ul> <p>The output shows the employee_id and the count of overlapping shifts for each employee who has at least one overlapping shift, ordered by employee_id in ascending order.</p> </div>
Database
SQL
SELECT t1.employee_id, COUNT(*) AS overlapping_shifts FROM EmployeeShifts t1 JOIN EmployeeShifts t2 ON t1.employee_id = t2.employee_id AND t1.start_time < t2.start_time AND t1.end_time > t2.start_time GROUP BY 1 HAVING overlapping_shifts > 0 ORDER BY 1;
3,263
Convert Doubly Linked List to Array I
Easy
<p>You are given the <code>head</code> of a <strong>doubly linked list</strong>, which contains nodes that have a next pointer and a previous pointer.</p> <p>Return an integer array which contains the elements of the linked list <strong>in order</strong>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">head = [1,2,3,4,3,2,1]</span></p> <p><strong>Output:</strong> <span class="example-io">[1,2,3,4,3,2,1]</span></p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">head = [2,2,2,2,2]</span></p> <p><strong>Output:</strong> <span class="example-io">[2,2,2,2,2]</span></p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">head = [3,2,3,2,3,2]</span></p> <p><strong>Output:</strong> <span class="example-io">[3,2,3,2,3,2]</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li>The number of nodes in the given list is in the range <code>[1, 50]</code>.</li> <li><code>1 &lt;= Node.val &lt;= 50</code></li> </ul>
Array; Linked List; Doubly-Linked List
C++
/** * Definition for doubly-linked list. * class Node { * int val; * Node* prev; * Node* next; * Node() : val(0), next(nullptr), prev(nullptr) {} * Node(int x) : val(x), next(nullptr), prev(nullptr) {} * Node(int x, Node *prev, Node *next) : val(x), next(next), prev(prev) {} * }; */ class Solution { public: vector<int> toArray(Node* head) { vector<int> ans; for (; head; head = head->next) { ans.push_back(head->val); } return ans; } };
3,263
Convert Doubly Linked List to Array I
Easy
<p>You are given the <code>head</code> of a <strong>doubly linked list</strong>, which contains nodes that have a next pointer and a previous pointer.</p> <p>Return an integer array which contains the elements of the linked list <strong>in order</strong>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">head = [1,2,3,4,3,2,1]</span></p> <p><strong>Output:</strong> <span class="example-io">[1,2,3,4,3,2,1]</span></p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">head = [2,2,2,2,2]</span></p> <p><strong>Output:</strong> <span class="example-io">[2,2,2,2,2]</span></p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">head = [3,2,3,2,3,2]</span></p> <p><strong>Output:</strong> <span class="example-io">[3,2,3,2,3,2]</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li>The number of nodes in the given list is in the range <code>[1, 50]</code>.</li> <li><code>1 &lt;= Node.val &lt;= 50</code></li> </ul>
Array; Linked List; Doubly-Linked List
Go
/** * Definition for a Node. * type Node struct { * Val int * Next *Node * Prev *Node * } */ func toArray(head *Node) (ans []int) { for ; head != nil; head = head.Next { ans = append(ans, head.Val) } return }
3,263
Convert Doubly Linked List to Array I
Easy
<p>You are given the <code>head</code> of a <strong>doubly linked list</strong>, which contains nodes that have a next pointer and a previous pointer.</p> <p>Return an integer array which contains the elements of the linked list <strong>in order</strong>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">head = [1,2,3,4,3,2,1]</span></p> <p><strong>Output:</strong> <span class="example-io">[1,2,3,4,3,2,1]</span></p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">head = [2,2,2,2,2]</span></p> <p><strong>Output:</strong> <span class="example-io">[2,2,2,2,2]</span></p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">head = [3,2,3,2,3,2]</span></p> <p><strong>Output:</strong> <span class="example-io">[3,2,3,2,3,2]</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li>The number of nodes in the given list is in the range <code>[1, 50]</code>.</li> <li><code>1 &lt;= Node.val &lt;= 50</code></li> </ul>
Array; Linked List; Doubly-Linked List
Java
/* // Definition for a Node. class Node { public int val; public Node prev; public Node next; }; */ class Solution { public int[] toArray(Node head) { List<Integer> ans = new ArrayList<>(); for (; head != null; head = head.next) { ans.add(head.val); } return ans.stream().mapToInt(i -> i).toArray(); } }
3,263
Convert Doubly Linked List to Array I
Easy
<p>You are given the <code>head</code> of a <strong>doubly linked list</strong>, which contains nodes that have a next pointer and a previous pointer.</p> <p>Return an integer array which contains the elements of the linked list <strong>in order</strong>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">head = [1,2,3,4,3,2,1]</span></p> <p><strong>Output:</strong> <span class="example-io">[1,2,3,4,3,2,1]</span></p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">head = [2,2,2,2,2]</span></p> <p><strong>Output:</strong> <span class="example-io">[2,2,2,2,2]</span></p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">head = [3,2,3,2,3,2]</span></p> <p><strong>Output:</strong> <span class="example-io">[3,2,3,2,3,2]</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li>The number of nodes in the given list is in the range <code>[1, 50]</code>.</li> <li><code>1 &lt;= Node.val &lt;= 50</code></li> </ul>
Array; Linked List; Doubly-Linked List
Python
""" # Definition for a Node. class Node: def __init__(self, val, prev=None, next=None): self.val = val self.prev = prev self.next = next """ class Solution: def toArray(self, root: "Optional[Node]") -> List[int]: ans = [] while root: ans.append(root.val) root = root.next return ans
3,263
Convert Doubly Linked List to Array I
Easy
<p>You are given the <code>head</code> of a <strong>doubly linked list</strong>, which contains nodes that have a next pointer and a previous pointer.</p> <p>Return an integer array which contains the elements of the linked list <strong>in order</strong>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">head = [1,2,3,4,3,2,1]</span></p> <p><strong>Output:</strong> <span class="example-io">[1,2,3,4,3,2,1]</span></p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">head = [2,2,2,2,2]</span></p> <p><strong>Output:</strong> <span class="example-io">[2,2,2,2,2]</span></p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">head = [3,2,3,2,3,2]</span></p> <p><strong>Output:</strong> <span class="example-io">[3,2,3,2,3,2]</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li>The number of nodes in the given list is in the range <code>[1, 50]</code>.</li> <li><code>1 &lt;= Node.val &lt;= 50</code></li> </ul>
Array; Linked List; Doubly-Linked List
TypeScript
/** * Definition for _Node. * class _Node { * val: number * prev: _Node | null * next: _Node | null * * constructor(val?: number, prev? : _Node, next? : _Node) { * this.val = (val===undefined ? 0 : val); * this.prev = (prev===undefined ? null : prev); * this.next = (next===undefined ? null : next); * } * } */ function toArray(head: _Node | null): number[] { const ans: number[] = []; for (; head; head = head.next) { ans.push(head.val); } return ans; }
3,264
Final Array State After K Multiplication Operations I
Easy
<p>You are given an integer array <code>nums</code>, an integer <code>k</code>, and an integer <code>multiplier</code>.</p> <p>You need to perform <code>k</code> operations on <code>nums</code>. In each operation:</p> <ul> <li>Find the <strong>minimum</strong> value <code>x</code> in <code>nums</code>. If there are multiple occurrences of the minimum value, select the one that appears <strong>first</strong>.</li> <li>Replace the selected minimum value <code>x</code> with <code>x * multiplier</code>.</li> </ul> <p>Return an integer array denoting the <em>final state</em> of <code>nums</code> after performing all <code>k</code> operations.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,1,3,5,6], k = 5, multiplier = 2</span></p> <p><strong>Output:</strong> <span class="example-io">[8,4,6,5,6]</span></p> <p><strong>Explanation:</strong></p> <table> <tbody> <tr> <th>Operation</th> <th>Result</th> </tr> <tr> <td>After operation 1</td> <td>[2, 2, 3, 5, 6]</td> </tr> <tr> <td>After operation 2</td> <td>[4, 2, 3, 5, 6]</td> </tr> <tr> <td>After operation 3</td> <td>[4, 4, 3, 5, 6]</td> </tr> <tr> <td>After operation 4</td> <td>[4, 4, 6, 5, 6]</td> </tr> <tr> <td>After operation 5</td> <td>[8, 4, 6, 5, 6]</td> </tr> </tbody> </table> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,2], k = 3, multiplier = 4</span></p> <p><strong>Output:</strong> <span class="example-io">[16,8]</span></p> <p><strong>Explanation:</strong></p> <table> <tbody> <tr> <th>Operation</th> <th>Result</th> </tr> <tr> <td>After operation 1</td> <td>[4, 2]</td> </tr> <tr> <td>After operation 2</td> <td>[4, 8]</td> </tr> <tr> <td>After operation 3</td> <td>[16, 8]</td> </tr> </tbody> </table> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 100</code></li> <li><code>1 &lt;= nums[i] &lt;= 100</code></li> <li><code>1 &lt;= k &lt;= 10</code></li> <li><code>1 &lt;= multiplier &lt;= 5</code></li> </ul>
Array; Math; Simulation; Heap (Priority Queue)
C++
class Solution { public: vector<int> getFinalState(vector<int>& nums, int k, int multiplier) { auto cmp = [&nums](int i, int j) { return nums[i] == nums[j] ? i > j : nums[i] > nums[j]; }; priority_queue<int, vector<int>, decltype(cmp)> pq(cmp); for (int i = 0; i < nums.size(); ++i) { pq.push(i); } while (k--) { int i = pq.top(); pq.pop(); nums[i] *= multiplier; pq.push(i); } return nums; } };
3,264
Final Array State After K Multiplication Operations I
Easy
<p>You are given an integer array <code>nums</code>, an integer <code>k</code>, and an integer <code>multiplier</code>.</p> <p>You need to perform <code>k</code> operations on <code>nums</code>. In each operation:</p> <ul> <li>Find the <strong>minimum</strong> value <code>x</code> in <code>nums</code>. If there are multiple occurrences of the minimum value, select the one that appears <strong>first</strong>.</li> <li>Replace the selected minimum value <code>x</code> with <code>x * multiplier</code>.</li> </ul> <p>Return an integer array denoting the <em>final state</em> of <code>nums</code> after performing all <code>k</code> operations.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,1,3,5,6], k = 5, multiplier = 2</span></p> <p><strong>Output:</strong> <span class="example-io">[8,4,6,5,6]</span></p> <p><strong>Explanation:</strong></p> <table> <tbody> <tr> <th>Operation</th> <th>Result</th> </tr> <tr> <td>After operation 1</td> <td>[2, 2, 3, 5, 6]</td> </tr> <tr> <td>After operation 2</td> <td>[4, 2, 3, 5, 6]</td> </tr> <tr> <td>After operation 3</td> <td>[4, 4, 3, 5, 6]</td> </tr> <tr> <td>After operation 4</td> <td>[4, 4, 6, 5, 6]</td> </tr> <tr> <td>After operation 5</td> <td>[8, 4, 6, 5, 6]</td> </tr> </tbody> </table> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,2], k = 3, multiplier = 4</span></p> <p><strong>Output:</strong> <span class="example-io">[16,8]</span></p> <p><strong>Explanation:</strong></p> <table> <tbody> <tr> <th>Operation</th> <th>Result</th> </tr> <tr> <td>After operation 1</td> <td>[4, 2]</td> </tr> <tr> <td>After operation 2</td> <td>[4, 8]</td> </tr> <tr> <td>After operation 3</td> <td>[16, 8]</td> </tr> </tbody> </table> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 100</code></li> <li><code>1 &lt;= nums[i] &lt;= 100</code></li> <li><code>1 &lt;= k &lt;= 10</code></li> <li><code>1 &lt;= multiplier &lt;= 5</code></li> </ul>
Array; Math; Simulation; Heap (Priority Queue)
Go
func getFinalState(nums []int, k int, multiplier int) []int { h := &hp{nums: nums} for i := range nums { heap.Push(h, i) } for k > 0 { i := heap.Pop(h).(int) nums[i] *= multiplier heap.Push(h, i) k-- } return nums } type hp struct { sort.IntSlice nums []int } func (h *hp) Less(i, j int) bool { if h.nums[h.IntSlice[i]] == h.nums[h.IntSlice[j]] { return h.IntSlice[i] < h.IntSlice[j] } return h.nums[h.IntSlice[i]] < h.nums[h.IntSlice[j]] } func (h *hp) Pop() any { old := h.IntSlice n := len(old) x := old[n-1] h.IntSlice = old[:n-1] return x } func (h *hp) Push(x any) { h.IntSlice = append(h.IntSlice, x.(int)) }
3,264
Final Array State After K Multiplication Operations I
Easy
<p>You are given an integer array <code>nums</code>, an integer <code>k</code>, and an integer <code>multiplier</code>.</p> <p>You need to perform <code>k</code> operations on <code>nums</code>. In each operation:</p> <ul> <li>Find the <strong>minimum</strong> value <code>x</code> in <code>nums</code>. If there are multiple occurrences of the minimum value, select the one that appears <strong>first</strong>.</li> <li>Replace the selected minimum value <code>x</code> with <code>x * multiplier</code>.</li> </ul> <p>Return an integer array denoting the <em>final state</em> of <code>nums</code> after performing all <code>k</code> operations.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,1,3,5,6], k = 5, multiplier = 2</span></p> <p><strong>Output:</strong> <span class="example-io">[8,4,6,5,6]</span></p> <p><strong>Explanation:</strong></p> <table> <tbody> <tr> <th>Operation</th> <th>Result</th> </tr> <tr> <td>After operation 1</td> <td>[2, 2, 3, 5, 6]</td> </tr> <tr> <td>After operation 2</td> <td>[4, 2, 3, 5, 6]</td> </tr> <tr> <td>After operation 3</td> <td>[4, 4, 3, 5, 6]</td> </tr> <tr> <td>After operation 4</td> <td>[4, 4, 6, 5, 6]</td> </tr> <tr> <td>After operation 5</td> <td>[8, 4, 6, 5, 6]</td> </tr> </tbody> </table> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,2], k = 3, multiplier = 4</span></p> <p><strong>Output:</strong> <span class="example-io">[16,8]</span></p> <p><strong>Explanation:</strong></p> <table> <tbody> <tr> <th>Operation</th> <th>Result</th> </tr> <tr> <td>After operation 1</td> <td>[4, 2]</td> </tr> <tr> <td>After operation 2</td> <td>[4, 8]</td> </tr> <tr> <td>After operation 3</td> <td>[16, 8]</td> </tr> </tbody> </table> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 100</code></li> <li><code>1 &lt;= nums[i] &lt;= 100</code></li> <li><code>1 &lt;= k &lt;= 10</code></li> <li><code>1 &lt;= multiplier &lt;= 5</code></li> </ul>
Array; Math; Simulation; Heap (Priority Queue)
Java
class Solution { public int[] getFinalState(int[] nums, int k, int multiplier) { PriorityQueue<Integer> pq = new PriorityQueue<>((i, j) -> nums[i] - nums[j] == 0 ? i - j : nums[i] - nums[j]); for (int i = 0; i < nums.length; i++) { pq.offer(i); } while (k-- > 0) { int i = pq.poll(); nums[i] *= multiplier; pq.offer(i); } return nums; } }
3,264
Final Array State After K Multiplication Operations I
Easy
<p>You are given an integer array <code>nums</code>, an integer <code>k</code>, and an integer <code>multiplier</code>.</p> <p>You need to perform <code>k</code> operations on <code>nums</code>. In each operation:</p> <ul> <li>Find the <strong>minimum</strong> value <code>x</code> in <code>nums</code>. If there are multiple occurrences of the minimum value, select the one that appears <strong>first</strong>.</li> <li>Replace the selected minimum value <code>x</code> with <code>x * multiplier</code>.</li> </ul> <p>Return an integer array denoting the <em>final state</em> of <code>nums</code> after performing all <code>k</code> operations.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,1,3,5,6], k = 5, multiplier = 2</span></p> <p><strong>Output:</strong> <span class="example-io">[8,4,6,5,6]</span></p> <p><strong>Explanation:</strong></p> <table> <tbody> <tr> <th>Operation</th> <th>Result</th> </tr> <tr> <td>After operation 1</td> <td>[2, 2, 3, 5, 6]</td> </tr> <tr> <td>After operation 2</td> <td>[4, 2, 3, 5, 6]</td> </tr> <tr> <td>After operation 3</td> <td>[4, 4, 3, 5, 6]</td> </tr> <tr> <td>After operation 4</td> <td>[4, 4, 6, 5, 6]</td> </tr> <tr> <td>After operation 5</td> <td>[8, 4, 6, 5, 6]</td> </tr> </tbody> </table> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,2], k = 3, multiplier = 4</span></p> <p><strong>Output:</strong> <span class="example-io">[16,8]</span></p> <p><strong>Explanation:</strong></p> <table> <tbody> <tr> <th>Operation</th> <th>Result</th> </tr> <tr> <td>After operation 1</td> <td>[4, 2]</td> </tr> <tr> <td>After operation 2</td> <td>[4, 8]</td> </tr> <tr> <td>After operation 3</td> <td>[16, 8]</td> </tr> </tbody> </table> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 100</code></li> <li><code>1 &lt;= nums[i] &lt;= 100</code></li> <li><code>1 &lt;= k &lt;= 10</code></li> <li><code>1 &lt;= multiplier &lt;= 5</code></li> </ul>
Array; Math; Simulation; Heap (Priority Queue)
Python
class Solution: def getFinalState(self, nums: List[int], k: int, multiplier: int) -> List[int]: pq = [(x, i) for i, x in enumerate(nums)] heapify(pq) for _ in range(k): _, i = heappop(pq) nums[i] *= multiplier heappush(pq, (nums[i], i)) return nums
3,264
Final Array State After K Multiplication Operations I
Easy
<p>You are given an integer array <code>nums</code>, an integer <code>k</code>, and an integer <code>multiplier</code>.</p> <p>You need to perform <code>k</code> operations on <code>nums</code>. In each operation:</p> <ul> <li>Find the <strong>minimum</strong> value <code>x</code> in <code>nums</code>. If there are multiple occurrences of the minimum value, select the one that appears <strong>first</strong>.</li> <li>Replace the selected minimum value <code>x</code> with <code>x * multiplier</code>.</li> </ul> <p>Return an integer array denoting the <em>final state</em> of <code>nums</code> after performing all <code>k</code> operations.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,1,3,5,6], k = 5, multiplier = 2</span></p> <p><strong>Output:</strong> <span class="example-io">[8,4,6,5,6]</span></p> <p><strong>Explanation:</strong></p> <table> <tbody> <tr> <th>Operation</th> <th>Result</th> </tr> <tr> <td>After operation 1</td> <td>[2, 2, 3, 5, 6]</td> </tr> <tr> <td>After operation 2</td> <td>[4, 2, 3, 5, 6]</td> </tr> <tr> <td>After operation 3</td> <td>[4, 4, 3, 5, 6]</td> </tr> <tr> <td>After operation 4</td> <td>[4, 4, 6, 5, 6]</td> </tr> <tr> <td>After operation 5</td> <td>[8, 4, 6, 5, 6]</td> </tr> </tbody> </table> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,2], k = 3, multiplier = 4</span></p> <p><strong>Output:</strong> <span class="example-io">[16,8]</span></p> <p><strong>Explanation:</strong></p> <table> <tbody> <tr> <th>Operation</th> <th>Result</th> </tr> <tr> <td>After operation 1</td> <td>[4, 2]</td> </tr> <tr> <td>After operation 2</td> <td>[4, 8]</td> </tr> <tr> <td>After operation 3</td> <td>[16, 8]</td> </tr> </tbody> </table> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 100</code></li> <li><code>1 &lt;= nums[i] &lt;= 100</code></li> <li><code>1 &lt;= k &lt;= 10</code></li> <li><code>1 &lt;= multiplier &lt;= 5</code></li> </ul>
Array; Math; Simulation; Heap (Priority Queue)
TypeScript
function getFinalState(nums: number[], k: number, multiplier: number): number[] { const pq = new PriorityQueue({ compare: (i, j) => (nums[i] === nums[j] ? i - j : nums[i] - nums[j]), }); for (let i = 0; i < nums.length; ++i) { pq.enqueue(i); } while (k--) { const i = pq.dequeue()!; nums[i] *= multiplier; pq.enqueue(i); } return nums; }
3,265
Count Almost Equal Pairs I
Medium
<p>You are given an array <code>nums</code> consisting of positive integers.</p> <p>We call two integers <code>x</code> and <code>y</code> in this problem <strong>almost equal</strong> if both integers can become equal after performing the following operation <strong>at most once</strong>:</p> <ul> <li>Choose <strong>either</strong> <code>x</code> or <code>y</code> and swap any two digits within the chosen number.</li> </ul> <p>Return the number of indices <code>i</code> and <code>j</code> in <code>nums</code> where <code>i &lt; j</code> such that <code>nums[i]</code> and <code>nums[j]</code> are <strong>almost equal</strong>.</p> <p><strong>Note</strong> that it is allowed for an integer to have leading zeros after performing an operation.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [3,12,30,17,21]</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>The almost equal pairs of elements are:</p> <ul> <li>3 and 30. By swapping 3 and 0 in 30, you get 3.</li> <li>12 and 21. By swapping 1 and 2 in 12, you get 21.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,1,1,1,1]</span></p> <p><strong>Output:</strong> <span class="example-io">10</span></p> <p><strong>Explanation:</strong></p> <p>Every two elements in the array are almost equal.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [123,231]</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>We cannot swap any two digits of 123 or 231 to reach the other.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= nums.length &lt;= 100</code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>6</sup></code></li> </ul>
Array; Hash Table; Counting; Enumeration; Sorting
C++
class Solution { public: int countPairs(vector<int>& nums) { sort(nums.begin(), nums.end()); int ans = 0; unordered_map<int, int> cnt; for (int x : nums) { unordered_set<int> vis = {x}; string s = to_string(x); for (int j = 0; j < s.length(); ++j) { for (int i = 0; i < j; ++i) { swap(s[i], s[j]); vis.insert(stoi(s)); swap(s[i], s[j]); } } for (int y : vis) { ans += cnt[y]; } cnt[x]++; } return ans; } };
3,265
Count Almost Equal Pairs I
Medium
<p>You are given an array <code>nums</code> consisting of positive integers.</p> <p>We call two integers <code>x</code> and <code>y</code> in this problem <strong>almost equal</strong> if both integers can become equal after performing the following operation <strong>at most once</strong>:</p> <ul> <li>Choose <strong>either</strong> <code>x</code> or <code>y</code> and swap any two digits within the chosen number.</li> </ul> <p>Return the number of indices <code>i</code> and <code>j</code> in <code>nums</code> where <code>i &lt; j</code> such that <code>nums[i]</code> and <code>nums[j]</code> are <strong>almost equal</strong>.</p> <p><strong>Note</strong> that it is allowed for an integer to have leading zeros after performing an operation.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [3,12,30,17,21]</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>The almost equal pairs of elements are:</p> <ul> <li>3 and 30. By swapping 3 and 0 in 30, you get 3.</li> <li>12 and 21. By swapping 1 and 2 in 12, you get 21.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,1,1,1,1]</span></p> <p><strong>Output:</strong> <span class="example-io">10</span></p> <p><strong>Explanation:</strong></p> <p>Every two elements in the array are almost equal.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [123,231]</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>We cannot swap any two digits of 123 or 231 to reach the other.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= nums.length &lt;= 100</code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>6</sup></code></li> </ul>
Array; Hash Table; Counting; Enumeration; Sorting
Go
func countPairs(nums []int) (ans int) { sort.Ints(nums) cnt := make(map[int]int) for _, x := range nums { vis := make(map[int]struct{}) vis[x] = struct{}{} s := []rune(strconv.Itoa(x)) for j := 0; j < len(s); j++ { for i := 0; i < j; i++ { s[i], s[j] = s[j], s[i] y, _ := strconv.Atoi(string(s)) vis[y] = struct{}{} s[i], s[j] = s[j], s[i] } } for y := range vis { ans += cnt[y] } cnt[x]++ } return }
3,265
Count Almost Equal Pairs I
Medium
<p>You are given an array <code>nums</code> consisting of positive integers.</p> <p>We call two integers <code>x</code> and <code>y</code> in this problem <strong>almost equal</strong> if both integers can become equal after performing the following operation <strong>at most once</strong>:</p> <ul> <li>Choose <strong>either</strong> <code>x</code> or <code>y</code> and swap any two digits within the chosen number.</li> </ul> <p>Return the number of indices <code>i</code> and <code>j</code> in <code>nums</code> where <code>i &lt; j</code> such that <code>nums[i]</code> and <code>nums[j]</code> are <strong>almost equal</strong>.</p> <p><strong>Note</strong> that it is allowed for an integer to have leading zeros after performing an operation.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [3,12,30,17,21]</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>The almost equal pairs of elements are:</p> <ul> <li>3 and 30. By swapping 3 and 0 in 30, you get 3.</li> <li>12 and 21. By swapping 1 and 2 in 12, you get 21.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,1,1,1,1]</span></p> <p><strong>Output:</strong> <span class="example-io">10</span></p> <p><strong>Explanation:</strong></p> <p>Every two elements in the array are almost equal.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [123,231]</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>We cannot swap any two digits of 123 or 231 to reach the other.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= nums.length &lt;= 100</code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>6</sup></code></li> </ul>
Array; Hash Table; Counting; Enumeration; Sorting
Java
class Solution { public int countPairs(int[] nums) { Arrays.sort(nums); int ans = 0; Map<Integer, Integer> cnt = new HashMap<>(); for (int x : nums) { Set<Integer> vis = new HashSet<>(); vis.add(x); char[] s = String.valueOf(x).toCharArray(); for (int j = 0; j < s.length; ++j) { for (int i = 0; i < j; ++i) { swap(s, i, j); vis.add(Integer.parseInt(String.valueOf(s))); swap(s, i, j); } } for (int y : vis) { ans += cnt.getOrDefault(y, 0); } cnt.merge(x, 1, Integer::sum); } return ans; } private void swap(char[] s, int i, int j) { char t = s[i]; s[i] = s[j]; s[j] = t; } }
3,265
Count Almost Equal Pairs I
Medium
<p>You are given an array <code>nums</code> consisting of positive integers.</p> <p>We call two integers <code>x</code> and <code>y</code> in this problem <strong>almost equal</strong> if both integers can become equal after performing the following operation <strong>at most once</strong>:</p> <ul> <li>Choose <strong>either</strong> <code>x</code> or <code>y</code> and swap any two digits within the chosen number.</li> </ul> <p>Return the number of indices <code>i</code> and <code>j</code> in <code>nums</code> where <code>i &lt; j</code> such that <code>nums[i]</code> and <code>nums[j]</code> are <strong>almost equal</strong>.</p> <p><strong>Note</strong> that it is allowed for an integer to have leading zeros after performing an operation.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [3,12,30,17,21]</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>The almost equal pairs of elements are:</p> <ul> <li>3 and 30. By swapping 3 and 0 in 30, you get 3.</li> <li>12 and 21. By swapping 1 and 2 in 12, you get 21.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,1,1,1,1]</span></p> <p><strong>Output:</strong> <span class="example-io">10</span></p> <p><strong>Explanation:</strong></p> <p>Every two elements in the array are almost equal.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [123,231]</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>We cannot swap any two digits of 123 or 231 to reach the other.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= nums.length &lt;= 100</code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>6</sup></code></li> </ul>
Array; Hash Table; Counting; Enumeration; Sorting
Python
class Solution: def countPairs(self, nums: List[int]) -> int: nums.sort() ans = 0 cnt = defaultdict(int) for x in nums: vis = {x} s = list(str(x)) for j in range(len(s)): for i in range(j): s[i], s[j] = s[j], s[i] vis.add(int("".join(s))) s[i], s[j] = s[j], s[i] ans += sum(cnt[x] for x in vis) cnt[x] += 1 return ans
3,265
Count Almost Equal Pairs I
Medium
<p>You are given an array <code>nums</code> consisting of positive integers.</p> <p>We call two integers <code>x</code> and <code>y</code> in this problem <strong>almost equal</strong> if both integers can become equal after performing the following operation <strong>at most once</strong>:</p> <ul> <li>Choose <strong>either</strong> <code>x</code> or <code>y</code> and swap any two digits within the chosen number.</li> </ul> <p>Return the number of indices <code>i</code> and <code>j</code> in <code>nums</code> where <code>i &lt; j</code> such that <code>nums[i]</code> and <code>nums[j]</code> are <strong>almost equal</strong>.</p> <p><strong>Note</strong> that it is allowed for an integer to have leading zeros after performing an operation.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [3,12,30,17,21]</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>The almost equal pairs of elements are:</p> <ul> <li>3 and 30. By swapping 3 and 0 in 30, you get 3.</li> <li>12 and 21. By swapping 1 and 2 in 12, you get 21.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,1,1,1,1]</span></p> <p><strong>Output:</strong> <span class="example-io">10</span></p> <p><strong>Explanation:</strong></p> <p>Every two elements in the array are almost equal.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [123,231]</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>We cannot swap any two digits of 123 or 231 to reach the other.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= nums.length &lt;= 100</code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>6</sup></code></li> </ul>
Array; Hash Table; Counting; Enumeration; Sorting
TypeScript
function countPairs(nums: number[]): number { nums.sort((a, b) => a - b); let ans = 0; const cnt = new Map<number, number>(); for (const x of nums) { const vis = new Set<number>(); vis.add(x); const s = x.toString().split(''); for (let j = 0; j < s.length; j++) { for (let i = 0; i < j; i++) { [s[i], s[j]] = [s[j], s[i]]; vis.add(+s.join('')); [s[i], s[j]] = [s[j], s[i]]; } } for (const y of vis) { ans += cnt.get(y) || 0; } cnt.set(x, (cnt.get(x) || 0) + 1); } return ans; }
3,266
Final Array State After K Multiplication Operations II
Hard
<p>You are given an integer array <code>nums</code>, an integer <code>k</code>, and an integer <code>multiplier</code>.</p> <p>You need to perform <code>k</code> operations on <code>nums</code>. In each operation:</p> <ul> <li>Find the <strong>minimum</strong> value <code>x</code> in <code>nums</code>. If there are multiple occurrences of the minimum value, select the one that appears <strong>first</strong>.</li> <li>Replace the selected minimum value <code>x</code> with <code>x * multiplier</code>.</li> </ul> <p>After the <code>k</code> operations, apply <strong>modulo</strong> <code>10<sup>9</sup> + 7</code> to every value in <code>nums</code>.</p> <p>Return an integer array denoting the <em>final state</em> of <code>nums</code> after performing all <code>k</code> operations and then applying the modulo.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,1,3,5,6], k = 5, multiplier = 2</span></p> <p><strong>Output:</strong> <span class="example-io">[8,4,6,5,6]</span></p> <p><strong>Explanation:</strong></p> <table> <tbody> <tr> <th>Operation</th> <th>Result</th> </tr> <tr> <td>After operation 1</td> <td>[2, 2, 3, 5, 6]</td> </tr> <tr> <td>After operation 2</td> <td>[4, 2, 3, 5, 6]</td> </tr> <tr> <td>After operation 3</td> <td>[4, 4, 3, 5, 6]</td> </tr> <tr> <td>After operation 4</td> <td>[4, 4, 6, 5, 6]</td> </tr> <tr> <td>After operation 5</td> <td>[8, 4, 6, 5, 6]</td> </tr> <tr> <td>After applying modulo</td> <td>[8, 4, 6, 5, 6]</td> </tr> </tbody> </table> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [100000,2000], k = 2, multiplier = 1000000</span></p> <p><strong>Output:</strong> <span class="example-io">[999999307,999999993]</span></p> <p><strong>Explanation:</strong></p> <table> <tbody> <tr> <th>Operation</th> <th>Result</th> </tr> <tr> <td>After operation 1</td> <td>[100000, 2000000000]</td> </tr> <tr> <td>After operation 2</td> <td>[100000000000, 2000000000]</td> </tr> <tr> <td>After applying modulo</td> <td>[999999307, 999999993]</td> </tr> </tbody> </table> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 10<sup>4</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li><code>1 &lt;= k &lt;= 10<sup>9</sup></code></li> <li><code>1 &lt;= multiplier &lt;= 10<sup>6</sup></code></li> </ul>
Array; Simulation; Heap (Priority Queue)
C++
class Solution { public: vector<int> getFinalState(vector<int>& nums, int k, int multiplier) { if (multiplier == 1) { return nums; } using ll = long long; using pli = pair<ll, int>; auto cmp = [](const pli& a, const pli& b) { if (a.first == b.first) { return a.second > b.second; } return a.first > b.first; }; priority_queue<pli, vector<pli>, decltype(cmp)> pq(cmp); int n = nums.size(); int m = *max_element(nums.begin(), nums.end()); for (int i = 0; i < n; ++i) { pq.emplace(nums[i], i); } while (k > 0 && pq.top().first < m) { auto p = pq.top(); pq.pop(); p.first *= multiplier; pq.emplace(p); --k; } auto qpow = [&](ll a, ll n, ll mod) { ll ans = 1 % mod; a = a % mod; while (n > 0) { if (n & 1) { ans = ans * a % mod; } a = a * a % mod; n >>= 1; } return ans; }; const int mod = 1e9 + 7; for (int i = 0; i < n; ++i) { auto p = pq.top(); pq.pop(); long long x = p.first; int j = p.second; nums[j] = static_cast<int>((x % mod) * qpow(multiplier, k / n + (i < k % n ? 1 : 0), mod) % mod); } return nums; } };
3,266
Final Array State After K Multiplication Operations II
Hard
<p>You are given an integer array <code>nums</code>, an integer <code>k</code>, and an integer <code>multiplier</code>.</p> <p>You need to perform <code>k</code> operations on <code>nums</code>. In each operation:</p> <ul> <li>Find the <strong>minimum</strong> value <code>x</code> in <code>nums</code>. If there are multiple occurrences of the minimum value, select the one that appears <strong>first</strong>.</li> <li>Replace the selected minimum value <code>x</code> with <code>x * multiplier</code>.</li> </ul> <p>After the <code>k</code> operations, apply <strong>modulo</strong> <code>10<sup>9</sup> + 7</code> to every value in <code>nums</code>.</p> <p>Return an integer array denoting the <em>final state</em> of <code>nums</code> after performing all <code>k</code> operations and then applying the modulo.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,1,3,5,6], k = 5, multiplier = 2</span></p> <p><strong>Output:</strong> <span class="example-io">[8,4,6,5,6]</span></p> <p><strong>Explanation:</strong></p> <table> <tbody> <tr> <th>Operation</th> <th>Result</th> </tr> <tr> <td>After operation 1</td> <td>[2, 2, 3, 5, 6]</td> </tr> <tr> <td>After operation 2</td> <td>[4, 2, 3, 5, 6]</td> </tr> <tr> <td>After operation 3</td> <td>[4, 4, 3, 5, 6]</td> </tr> <tr> <td>After operation 4</td> <td>[4, 4, 6, 5, 6]</td> </tr> <tr> <td>After operation 5</td> <td>[8, 4, 6, 5, 6]</td> </tr> <tr> <td>After applying modulo</td> <td>[8, 4, 6, 5, 6]</td> </tr> </tbody> </table> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [100000,2000], k = 2, multiplier = 1000000</span></p> <p><strong>Output:</strong> <span class="example-io">[999999307,999999993]</span></p> <p><strong>Explanation:</strong></p> <table> <tbody> <tr> <th>Operation</th> <th>Result</th> </tr> <tr> <td>After operation 1</td> <td>[100000, 2000000000]</td> </tr> <tr> <td>After operation 2</td> <td>[100000000000, 2000000000]</td> </tr> <tr> <td>After applying modulo</td> <td>[999999307, 999999993]</td> </tr> </tbody> </table> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 10<sup>4</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li><code>1 &lt;= k &lt;= 10<sup>9</sup></code></li> <li><code>1 &lt;= multiplier &lt;= 10<sup>6</sup></code></li> </ul>
Array; Simulation; Heap (Priority Queue)
Go
func getFinalState(nums []int, k int, multiplier int) []int { if multiplier == 1 { return nums } n := len(nums) pq := make(hp, n) for i, x := range nums { pq[i] = pair{x, i} } heap.Init(&pq) m := slices.Max(nums) for ; k > 0 && pq[0].x < m; k-- { x := pq[0] heap.Pop(&pq) x.x *= multiplier heap.Push(&pq, x) } const mod int = 1e9 + 7 for i := range nums { p := heap.Pop(&pq).(pair) x, j := p.x, p.i power := k / n if i < k%n { power++ } nums[j] = (x % mod) * qpow(multiplier, power, mod) % mod } return nums } func qpow(a, n, mod int) int { ans := 1 % mod a = a % mod for n > 0 { if n&1 == 1 { ans = (ans * a) % mod } a = (a * a) % mod n >>= 1 } return int(ans) } type pair struct{ x, i int } type hp []pair func (h hp) Len() int { return len(h) } func (h hp) Less(i, j int) bool { return h[i].x < h[j].x || h[i].x == h[j].x && h[i].i < h[j].i } func (h hp) Swap(i, j int) { h[i], h[j] = h[j], h[i] } func (h *hp) Push(x any) { *h = append(*h, x.(pair)) } func (h *hp) Pop() (x any) { a := *h; x = a[len(a)-1]; *h = a[:len(a)-1]; return x }
3,266
Final Array State After K Multiplication Operations II
Hard
<p>You are given an integer array <code>nums</code>, an integer <code>k</code>, and an integer <code>multiplier</code>.</p> <p>You need to perform <code>k</code> operations on <code>nums</code>. In each operation:</p> <ul> <li>Find the <strong>minimum</strong> value <code>x</code> in <code>nums</code>. If there are multiple occurrences of the minimum value, select the one that appears <strong>first</strong>.</li> <li>Replace the selected minimum value <code>x</code> with <code>x * multiplier</code>.</li> </ul> <p>After the <code>k</code> operations, apply <strong>modulo</strong> <code>10<sup>9</sup> + 7</code> to every value in <code>nums</code>.</p> <p>Return an integer array denoting the <em>final state</em> of <code>nums</code> after performing all <code>k</code> operations and then applying the modulo.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,1,3,5,6], k = 5, multiplier = 2</span></p> <p><strong>Output:</strong> <span class="example-io">[8,4,6,5,6]</span></p> <p><strong>Explanation:</strong></p> <table> <tbody> <tr> <th>Operation</th> <th>Result</th> </tr> <tr> <td>After operation 1</td> <td>[2, 2, 3, 5, 6]</td> </tr> <tr> <td>After operation 2</td> <td>[4, 2, 3, 5, 6]</td> </tr> <tr> <td>After operation 3</td> <td>[4, 4, 3, 5, 6]</td> </tr> <tr> <td>After operation 4</td> <td>[4, 4, 6, 5, 6]</td> </tr> <tr> <td>After operation 5</td> <td>[8, 4, 6, 5, 6]</td> </tr> <tr> <td>After applying modulo</td> <td>[8, 4, 6, 5, 6]</td> </tr> </tbody> </table> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [100000,2000], k = 2, multiplier = 1000000</span></p> <p><strong>Output:</strong> <span class="example-io">[999999307,999999993]</span></p> <p><strong>Explanation:</strong></p> <table> <tbody> <tr> <th>Operation</th> <th>Result</th> </tr> <tr> <td>After operation 1</td> <td>[100000, 2000000000]</td> </tr> <tr> <td>After operation 2</td> <td>[100000000000, 2000000000]</td> </tr> <tr> <td>After applying modulo</td> <td>[999999307, 999999993]</td> </tr> </tbody> </table> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 10<sup>4</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li><code>1 &lt;= k &lt;= 10<sup>9</sup></code></li> <li><code>1 &lt;= multiplier &lt;= 10<sup>6</sup></code></li> </ul>
Array; Simulation; Heap (Priority Queue)
Java
class Solution { public int[] getFinalState(int[] nums, int k, int multiplier) { if (multiplier == 1) { return nums; } PriorityQueue<long[]> pq = new PriorityQueue<>( (a, b) -> a[0] == b[0] ? Long.compare(a[1], b[1]) : Long.compare(a[0], b[0])); int n = nums.length; int m = Arrays.stream(nums).max().getAsInt(); for (int i = 0; i < n; ++i) { pq.offer(new long[] {nums[i], i}); } for (; k > 0 && pq.peek()[0] < m; --k) { long[] p = pq.poll(); p[0] *= multiplier; pq.offer(p); } final int mod = (int) 1e9 + 7; for (int i = 0; i < n; ++i) { long[] p = pq.poll(); long x = p[0]; int j = (int) p[1]; nums[j] = (int) ((x % mod) * qpow(multiplier, k / n + (i < k % n ? 1 : 0), mod) % mod); } return nums; } private int qpow(long a, long n, long mod) { long ans = 1 % mod; for (; n > 0; n >>= 1) { if ((n & 1) == 1) { ans = ans * a % mod; } a = a * a % mod; } return (int) ans; } }
3,266
Final Array State After K Multiplication Operations II
Hard
<p>You are given an integer array <code>nums</code>, an integer <code>k</code>, and an integer <code>multiplier</code>.</p> <p>You need to perform <code>k</code> operations on <code>nums</code>. In each operation:</p> <ul> <li>Find the <strong>minimum</strong> value <code>x</code> in <code>nums</code>. If there are multiple occurrences of the minimum value, select the one that appears <strong>first</strong>.</li> <li>Replace the selected minimum value <code>x</code> with <code>x * multiplier</code>.</li> </ul> <p>After the <code>k</code> operations, apply <strong>modulo</strong> <code>10<sup>9</sup> + 7</code> to every value in <code>nums</code>.</p> <p>Return an integer array denoting the <em>final state</em> of <code>nums</code> after performing all <code>k</code> operations and then applying the modulo.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,1,3,5,6], k = 5, multiplier = 2</span></p> <p><strong>Output:</strong> <span class="example-io">[8,4,6,5,6]</span></p> <p><strong>Explanation:</strong></p> <table> <tbody> <tr> <th>Operation</th> <th>Result</th> </tr> <tr> <td>After operation 1</td> <td>[2, 2, 3, 5, 6]</td> </tr> <tr> <td>After operation 2</td> <td>[4, 2, 3, 5, 6]</td> </tr> <tr> <td>After operation 3</td> <td>[4, 4, 3, 5, 6]</td> </tr> <tr> <td>After operation 4</td> <td>[4, 4, 6, 5, 6]</td> </tr> <tr> <td>After operation 5</td> <td>[8, 4, 6, 5, 6]</td> </tr> <tr> <td>After applying modulo</td> <td>[8, 4, 6, 5, 6]</td> </tr> </tbody> </table> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [100000,2000], k = 2, multiplier = 1000000</span></p> <p><strong>Output:</strong> <span class="example-io">[999999307,999999993]</span></p> <p><strong>Explanation:</strong></p> <table> <tbody> <tr> <th>Operation</th> <th>Result</th> </tr> <tr> <td>After operation 1</td> <td>[100000, 2000000000]</td> </tr> <tr> <td>After operation 2</td> <td>[100000000000, 2000000000]</td> </tr> <tr> <td>After applying modulo</td> <td>[999999307, 999999993]</td> </tr> </tbody> </table> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 10<sup>4</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>9</sup></code></li> <li><code>1 &lt;= k &lt;= 10<sup>9</sup></code></li> <li><code>1 &lt;= multiplier &lt;= 10<sup>6</sup></code></li> </ul>
Array; Simulation; Heap (Priority Queue)
Python
class Solution: def getFinalState(self, nums: List[int], k: int, multiplier: int) -> List[int]: if multiplier == 1: return nums pq = [(x, i) for i, x in enumerate(nums)] heapify(pq) m = max(nums) while k and pq[0][0] < m: x, i = heappop(pq) heappush(pq, (x * multiplier, i)) k -= 1 n = len(nums) mod = 10**9 + 7 pq.sort() for i, (x, j) in enumerate(pq): nums[j] = x * pow(multiplier, k // n + int(i < k % n), mod) % mod return nums
3,267
Count Almost Equal Pairs II
Hard
<p><strong>Attention</strong>: In this version, the number of operations that can be performed, has been increased to <strong>twice</strong>.<!-- notionvc: 278e7cb2-3b05-42fa-8ae9-65f5fd6f7585 --></p> <p>You are given an array <code>nums</code> consisting of positive integers.</p> <p>We call two integers <code>x</code> and <code>y</code> <strong>almost equal</strong> if both integers can become equal after performing the following operation <strong>at most <u>twice</u></strong>:</p> <ul> <li>Choose <strong>either</strong> <code>x</code> or <code>y</code> and swap any two digits within the chosen number.</li> </ul> <p>Return the number of indices <code>i</code> and <code>j</code> in <code>nums</code> where <code>i &lt; j</code> such that <code>nums[i]</code> and <code>nums[j]</code> are <strong>almost equal</strong>.</p> <p><strong>Note</strong> that it is allowed for an integer to have leading zeros after performing an operation.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1023,2310,2130,213]</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <p>The almost equal pairs of elements are:</p> <ul> <li>1023 and 2310. By swapping the digits 1 and 2, and then the digits 0 and 3 in 1023, you get 2310.</li> <li>1023 and 213. By swapping the digits 1 and 0, and then the digits 1 and 2 in 1023, you get 0213, which is 213.</li> <li>2310 and 213. By swapping the digits 2 and 0, and then the digits 3 and 2 in 2310, you get 0213, which is 213.</li> <li>2310 and 2130. By swapping the digits 3 and 1 in 2310, you get 2130.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,10,100]</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></p> <p><strong>Explanation:</strong></p> <p>The almost equal pairs of elements are:</p> <ul> <li>1 and 10. By swapping the digits 1 and 0 in 10, you get 01 which is 1.</li> <li>1 and 100. By swapping the second 0 with the digit 1 in 100, you get 001, which is 1.</li> <li>10 and 100. By swapping the first 0 with the digit 1 in 100, you get 010, which is 10.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= nums.length &lt;= 5000</code></li> <li><code>1 &lt;= nums[i] &lt; 10<sup>7</sup></code></li> </ul>
Array; Hash Table; Counting; Enumeration; Sorting
C++
class Solution { public: int countPairs(vector<int>& nums) { sort(nums.begin(), nums.end()); int ans = 0; unordered_map<int, int> cnt; for (int x : nums) { unordered_set<int> vis = {x}; string s = to_string(x); for (int j = 0; j < s.length(); ++j) { for (int i = 0; i < j; ++i) { swap(s[i], s[j]); vis.insert(stoi(s)); for (int q = i + 1; q < s.length(); ++q) { for (int p = i + 1; p < q; ++p) { swap(s[p], s[q]); vis.insert(stoi(s)); swap(s[p], s[q]); } } swap(s[i], s[j]); } } for (int y : vis) { ans += cnt[y]; } cnt[x]++; } return ans; } };
3,267
Count Almost Equal Pairs II
Hard
<p><strong>Attention</strong>: In this version, the number of operations that can be performed, has been increased to <strong>twice</strong>.<!-- notionvc: 278e7cb2-3b05-42fa-8ae9-65f5fd6f7585 --></p> <p>You are given an array <code>nums</code> consisting of positive integers.</p> <p>We call two integers <code>x</code> and <code>y</code> <strong>almost equal</strong> if both integers can become equal after performing the following operation <strong>at most <u>twice</u></strong>:</p> <ul> <li>Choose <strong>either</strong> <code>x</code> or <code>y</code> and swap any two digits within the chosen number.</li> </ul> <p>Return the number of indices <code>i</code> and <code>j</code> in <code>nums</code> where <code>i &lt; j</code> such that <code>nums[i]</code> and <code>nums[j]</code> are <strong>almost equal</strong>.</p> <p><strong>Note</strong> that it is allowed for an integer to have leading zeros after performing an operation.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1023,2310,2130,213]</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <p>The almost equal pairs of elements are:</p> <ul> <li>1023 and 2310. By swapping the digits 1 and 2, and then the digits 0 and 3 in 1023, you get 2310.</li> <li>1023 and 213. By swapping the digits 1 and 0, and then the digits 1 and 2 in 1023, you get 0213, which is 213.</li> <li>2310 and 213. By swapping the digits 2 and 0, and then the digits 3 and 2 in 2310, you get 0213, which is 213.</li> <li>2310 and 2130. By swapping the digits 3 and 1 in 2310, you get 2130.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,10,100]</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></p> <p><strong>Explanation:</strong></p> <p>The almost equal pairs of elements are:</p> <ul> <li>1 and 10. By swapping the digits 1 and 0 in 10, you get 01 which is 1.</li> <li>1 and 100. By swapping the second 0 with the digit 1 in 100, you get 001, which is 1.</li> <li>10 and 100. By swapping the first 0 with the digit 1 in 100, you get 010, which is 10.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= nums.length &lt;= 5000</code></li> <li><code>1 &lt;= nums[i] &lt; 10<sup>7</sup></code></li> </ul>
Array; Hash Table; Counting; Enumeration; Sorting
Go
func countPairs(nums []int) (ans int) { sort.Ints(nums) cnt := make(map[int]int) for _, x := range nums { vis := make(map[int]struct{}) vis[x] = struct{}{} s := []rune(strconv.Itoa(x)) for j := 0; j < len(s); j++ { for i := 0; i < j; i++ { s[i], s[j] = s[j], s[i] y, _ := strconv.Atoi(string(s)) vis[y] = struct{}{} for q := i + 1; q < len(s); q++ { for p := i + 1; p < q; p++ { s[p], s[q] = s[q], s[p] z, _ := strconv.Atoi(string(s)) vis[z] = struct{}{} s[p], s[q] = s[q], s[p] } } s[i], s[j] = s[j], s[i] } } for y := range vis { ans += cnt[y] } cnt[x]++ } return }
3,267
Count Almost Equal Pairs II
Hard
<p><strong>Attention</strong>: In this version, the number of operations that can be performed, has been increased to <strong>twice</strong>.<!-- notionvc: 278e7cb2-3b05-42fa-8ae9-65f5fd6f7585 --></p> <p>You are given an array <code>nums</code> consisting of positive integers.</p> <p>We call two integers <code>x</code> and <code>y</code> <strong>almost equal</strong> if both integers can become equal after performing the following operation <strong>at most <u>twice</u></strong>:</p> <ul> <li>Choose <strong>either</strong> <code>x</code> or <code>y</code> and swap any two digits within the chosen number.</li> </ul> <p>Return the number of indices <code>i</code> and <code>j</code> in <code>nums</code> where <code>i &lt; j</code> such that <code>nums[i]</code> and <code>nums[j]</code> are <strong>almost equal</strong>.</p> <p><strong>Note</strong> that it is allowed for an integer to have leading zeros after performing an operation.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1023,2310,2130,213]</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <p>The almost equal pairs of elements are:</p> <ul> <li>1023 and 2310. By swapping the digits 1 and 2, and then the digits 0 and 3 in 1023, you get 2310.</li> <li>1023 and 213. By swapping the digits 1 and 0, and then the digits 1 and 2 in 1023, you get 0213, which is 213.</li> <li>2310 and 213. By swapping the digits 2 and 0, and then the digits 3 and 2 in 2310, you get 0213, which is 213.</li> <li>2310 and 2130. By swapping the digits 3 and 1 in 2310, you get 2130.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,10,100]</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></p> <p><strong>Explanation:</strong></p> <p>The almost equal pairs of elements are:</p> <ul> <li>1 and 10. By swapping the digits 1 and 0 in 10, you get 01 which is 1.</li> <li>1 and 100. By swapping the second 0 with the digit 1 in 100, you get 001, which is 1.</li> <li>10 and 100. By swapping the first 0 with the digit 1 in 100, you get 010, which is 10.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= nums.length &lt;= 5000</code></li> <li><code>1 &lt;= nums[i] &lt; 10<sup>7</sup></code></li> </ul>
Array; Hash Table; Counting; Enumeration; Sorting
Java
class Solution { public int countPairs(int[] nums) { Arrays.sort(nums); int ans = 0; Map<Integer, Integer> cnt = new HashMap<>(); for (int x : nums) { Set<Integer> vis = new HashSet<>(); vis.add(x); char[] s = String.valueOf(x).toCharArray(); for (int j = 0; j < s.length; ++j) { for (int i = 0; i < j; ++i) { swap(s, i, j); vis.add(Integer.parseInt(String.valueOf(s))); for (int q = i; q < s.length; ++q) { for (int p = i; p < q; ++p) { swap(s, p, q); vis.add(Integer.parseInt(String.valueOf(s))); swap(s, p, q); } } swap(s, i, j); } } for (int y : vis) { ans += cnt.getOrDefault(y, 0); } cnt.merge(x, 1, Integer::sum); } return ans; } private void swap(char[] s, int i, int j) { char t = s[i]; s[i] = s[j]; s[j] = t; } }
3,267
Count Almost Equal Pairs II
Hard
<p><strong>Attention</strong>: In this version, the number of operations that can be performed, has been increased to <strong>twice</strong>.<!-- notionvc: 278e7cb2-3b05-42fa-8ae9-65f5fd6f7585 --></p> <p>You are given an array <code>nums</code> consisting of positive integers.</p> <p>We call two integers <code>x</code> and <code>y</code> <strong>almost equal</strong> if both integers can become equal after performing the following operation <strong>at most <u>twice</u></strong>:</p> <ul> <li>Choose <strong>either</strong> <code>x</code> or <code>y</code> and swap any two digits within the chosen number.</li> </ul> <p>Return the number of indices <code>i</code> and <code>j</code> in <code>nums</code> where <code>i &lt; j</code> such that <code>nums[i]</code> and <code>nums[j]</code> are <strong>almost equal</strong>.</p> <p><strong>Note</strong> that it is allowed for an integer to have leading zeros after performing an operation.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1023,2310,2130,213]</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <p>The almost equal pairs of elements are:</p> <ul> <li>1023 and 2310. By swapping the digits 1 and 2, and then the digits 0 and 3 in 1023, you get 2310.</li> <li>1023 and 213. By swapping the digits 1 and 0, and then the digits 1 and 2 in 1023, you get 0213, which is 213.</li> <li>2310 and 213. By swapping the digits 2 and 0, and then the digits 3 and 2 in 2310, you get 0213, which is 213.</li> <li>2310 and 2130. By swapping the digits 3 and 1 in 2310, you get 2130.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,10,100]</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></p> <p><strong>Explanation:</strong></p> <p>The almost equal pairs of elements are:</p> <ul> <li>1 and 10. By swapping the digits 1 and 0 in 10, you get 01 which is 1.</li> <li>1 and 100. By swapping the second 0 with the digit 1 in 100, you get 001, which is 1.</li> <li>10 and 100. By swapping the first 0 with the digit 1 in 100, you get 010, which is 10.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= nums.length &lt;= 5000</code></li> <li><code>1 &lt;= nums[i] &lt; 10<sup>7</sup></code></li> </ul>
Array; Hash Table; Counting; Enumeration; Sorting
Python
class Solution: def countPairs(self, nums: List[int]) -> int: nums.sort() ans = 0 cnt = defaultdict(int) for x in nums: vis = {x} s = list(str(x)) m = len(s) for j in range(m): for i in range(j): s[i], s[j] = s[j], s[i] vis.add(int("".join(s))) for q in range(i + 1, m): for p in range(i + 1, q): s[p], s[q] = s[q], s[p] vis.add(int("".join(s))) s[p], s[q] = s[q], s[p] s[i], s[j] = s[j], s[i] ans += sum(cnt[x] for x in vis) cnt[x] += 1 return ans
3,267
Count Almost Equal Pairs II
Hard
<p><strong>Attention</strong>: In this version, the number of operations that can be performed, has been increased to <strong>twice</strong>.<!-- notionvc: 278e7cb2-3b05-42fa-8ae9-65f5fd6f7585 --></p> <p>You are given an array <code>nums</code> consisting of positive integers.</p> <p>We call two integers <code>x</code> and <code>y</code> <strong>almost equal</strong> if both integers can become equal after performing the following operation <strong>at most <u>twice</u></strong>:</p> <ul> <li>Choose <strong>either</strong> <code>x</code> or <code>y</code> and swap any two digits within the chosen number.</li> </ul> <p>Return the number of indices <code>i</code> and <code>j</code> in <code>nums</code> where <code>i &lt; j</code> such that <code>nums[i]</code> and <code>nums[j]</code> are <strong>almost equal</strong>.</p> <p><strong>Note</strong> that it is allowed for an integer to have leading zeros after performing an operation.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1023,2310,2130,213]</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <p>The almost equal pairs of elements are:</p> <ul> <li>1023 and 2310. By swapping the digits 1 and 2, and then the digits 0 and 3 in 1023, you get 2310.</li> <li>1023 and 213. By swapping the digits 1 and 0, and then the digits 1 and 2 in 1023, you get 0213, which is 213.</li> <li>2310 and 213. By swapping the digits 2 and 0, and then the digits 3 and 2 in 2310, you get 0213, which is 213.</li> <li>2310 and 2130. By swapping the digits 3 and 1 in 2310, you get 2130.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [1,10,100]</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></p> <p><strong>Explanation:</strong></p> <p>The almost equal pairs of elements are:</p> <ul> <li>1 and 10. By swapping the digits 1 and 0 in 10, you get 01 which is 1.</li> <li>1 and 100. By swapping the second 0 with the digit 1 in 100, you get 001, which is 1.</li> <li>10 and 100. By swapping the first 0 with the digit 1 in 100, you get 010, which is 10.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= nums.length &lt;= 5000</code></li> <li><code>1 &lt;= nums[i] &lt; 10<sup>7</sup></code></li> </ul>
Array; Hash Table; Counting; Enumeration; Sorting
TypeScript
function countPairs(nums: number[]): number { nums.sort((a, b) => a - b); let ans = 0; const cnt = new Map<number, number>(); for (const x of nums) { const vis = new Set<number>(); vis.add(x); const s = x.toString().split(''); for (let j = 0; j < s.length; j++) { for (let i = 0; i < j; i++) { [s[i], s[j]] = [s[j], s[i]]; vis.add(+s.join('')); for (let q = i + 1; q < s.length; ++q) { for (let p = i + 1; p < q; ++p) { [s[p], s[q]] = [s[q], s[p]]; vis.add(+s.join('')); [s[p], s[q]] = [s[q], s[p]]; } } [s[i], s[j]] = [s[j], s[i]]; } } for (const y of vis) { ans += cnt.get(y) || 0; } cnt.set(x, (cnt.get(x) || 0) + 1); } return ans; }
3,268
Find Overlapping Shifts II
Hard
<p>Table: <code>EmployeeShifts</code></p> <pre> +------------------+----------+ | Column Name | Type | +------------------+----------+ | employee_id | int | | start_time | datetime | | end_time | datetime | +------------------+----------+ (employee_id, start_time) is the unique key for this table. This table contains information about the shifts worked by employees, including the start time, and end time. </pre> <p>Write a solution to analyze overlapping shifts for each employee. Two shifts are considered overlapping if they occur on the <strong>same date</strong> and one shift&#39;s <code>end_time</code> is <strong>later than</strong> another shift&#39;s <code>start_time</code>.</p> <p>For <strong>each employee</strong>, calculate the following:</p> <ol> <li>The <strong>maximum</strong> number of shifts that <strong>overlap</strong> at any <strong>given time</strong>.</li> <li>The <strong>total duration</strong> of all overlaps in minutes.</li> </ol> <p><em>Return the result table ordered by</em> <code>employee_id</code> <em>in <strong>ascending</strong> order</em>.</p> <p>The query result format is in the following example.</p> <p>&nbsp;</p> <p><strong class="example">Example:</strong></p> <div class="example-block"> <p><strong>Input:</strong></p> <p><code>EmployeeShifts</code> table:</p> <pre class="example-io"> +-------------+---------------------+---------------------+ | employee_id | start_time | end_time | +-------------+---------------------+---------------------+ | 1 | 2023-10-01 09:00:00 | 2023-10-01 17:00:00 | | 1 | 2023-10-01 15:00:00 | 2023-10-01 23:00:00 | | 1 | 2023-10-01 16:00:00 | 2023-10-02 00:00:00 | | 2 | 2023-10-01 09:00:00 | 2023-10-01 17:00:00 | | 2 | 2023-10-01 11:00:00 | 2023-10-01 19:00:00 | | 3 | 2023-10-01 09:00:00 | 2023-10-01 17:00:00 | +-------------+---------------------+---------------------+ </pre> <p><strong>Output:</strong></p> <pre class="example-io"> +-------------+---------------------------+------------------------+ | employee_id | max_overlapping_shifts | total_overlap_duration | +-------------+---------------------------+------------------------+ | 1 | 3 | 600 | | 2 | 2 | 360 | | 3 | 1 | 0 | +-------------+---------------------------+------------------------+ </pre> <p><strong>Explanation:</strong></p> <ul> <li>Employee 1 has 3 shifts: <ul> <li>2023-10-01 09:00:00 to 2023-10-01 17:00:00</li> <li>2023-10-01 15:00:00 to 2023-10-01 23:00:00</li> <li>2023-10-01 16:00:00 to 2023-10-02 00:00:00</li> </ul> The maximum number of overlapping shifts is 3 (from 16:00 to 17:00). The total overlap duration is: - 2 hours (15:00-17:00) between 1st and 2nd shifts - 1 hour (16:00-17:00) between 1st and 3rd shifts - 7 hours (16:00-23:00) between 2nd and 3rd shifts Total: 10 hours = 600 minutes</li> <li>Employee 2 has 2 shifts: <ul> <li>2023-10-01 09:00:00 to 2023-10-01 17:00:00</li> <li>2023-10-01 11:00:00 to 2023-10-01 19:00:00</li> </ul> The maximum number of overlapping shifts is 2. The total overlap duration is 6 hours (11:00-17:00) = 360 minutes.</li> <li>Employee 3 has only 1 shift, so there are no overlaps.</li> </ul> <p>The output table contains the employee_id, the maximum number of simultaneous overlaps, and the total overlap duration in minutes for each employee, ordered by employee_id in ascending order.</p> </div>
Database
SQL
WITH T AS ( SELECT DISTINCT employee_id, start_time AS st FROM EmployeeShifts UNION DISTINCT SELECT DISTINCT employee_id, end_time AS st FROM EmployeeShifts ), P AS ( SELECT *, LEAD(st) OVER ( PARTITION BY employee_id ORDER BY st ) AS ed FROM T ), S AS ( SELECT P.*, COUNT(1) AS concurrent_count FROM P INNER JOIN EmployeeShifts USING (employee_id) WHERE P.st >= EmployeeShifts.start_time AND P.ed <= EmployeeShifts.end_time GROUP BY 1, 2, 3 ), U AS ( SELECT t1.employee_id, SUM( TIMESTAMPDIFF(MINUTE, t2.start_time, LEAST(t1.end_time, t2.end_time)) ) total_overlap_duration FROM EmployeeShifts t1 JOIN EmployeeShifts t2 ON t1.employee_id = t2.employee_id AND t1.start_time < t2.start_time AND t1.end_time > t2.start_time GROUP BY 1 ) SELECT employee_id, MAX(concurrent_count) max_overlapping_shifts, IFNULL(AVG(total_overlap_duration), 0) total_overlap_duration FROM S LEFT JOIN U USING (employee_id) GROUP BY 1 ORDER BY 1;
3,269
Constructing Two Increasing Arrays
Hard
<p>Given 2 integer arrays <code>nums1</code> and <code>nums2</code> consisting only of 0 and 1, your task is to calculate the <strong>minimum</strong> possible <strong>largest</strong> number in arrays <code>nums1</code> and <code>nums2</code>, after doing the following.</p> <p>Replace every 0 with an <em>even positive integer</em> and every 1 with an <em>odd positive integer</em>. After replacement, both arrays should be <strong>increasing</strong> and each integer should be used <strong>at most</strong> once.</p> <p>Return the <em>minimum possible largest number</em> after applying the changes.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums1 = [], nums2 = [1,0,1,1]</span></p> <p><strong>Output:</strong> <span class="example-io">5</span></p> <p><strong>Explanation:</strong></p> <p>After replacing, <code>nums1 = []</code>, and <code>nums2 = [1, 2, 3, 5]</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums1 = [0,1,0,1], nums2 = [1,0,0,1]</span></p> <p><strong>Output:</strong> <span class="example-io">9</span></p> <p><strong>Explanation:</strong></p> <p>One way to replace, having 9 as the largest element is <code>nums1 = [2, 3, 8, 9]</code>, and <code>nums2 = [1, 4, 6, 7]</code>.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums1 = [0,1,0,0,1], nums2 = [0,0,0,1]</span></p> <p><strong>Output:</strong> <span class="example-io">13</span></p> <p><strong>Explanation:</strong></p> <p>One way to replace, having 13 as the largest element is <code>nums1 = [2, 3, 4, 6, 7]</code>, and <code>nums2 = [8, 10, 12, 13]</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>0 &lt;= nums1.length &lt;= 1000</code></li> <li><code>1 &lt;= nums2.length &lt;= 1000</code></li> <li><code>nums1</code> and <code>nums2</code> consist only of 0 and 1.</li> </ul>
Array; Dynamic Programming
C++
class Solution { public: int minLargest(vector<int>& nums1, vector<int>& nums2) { int m = nums1.size(), n = nums2.size(); int f[m + 1][n + 1]; memset(f, 0, sizeof(f)); auto nxt = [](int x, int y) -> int { return (x & 1 ^ y) == 1 ? x + 1 : x + 2; }; for (int i = 1; i <= m; ++i) { f[i][0] = nxt(f[i - 1][0], nums1[i - 1]); } for (int j = 1; j <= n; ++j) { f[0][j] = nxt(f[0][j - 1], nums2[j - 1]); } for (int i = 1; i <= m; ++i) { for (int j = 1; j <= n; ++j) { int x = nxt(f[i - 1][j], nums1[i - 1]); int y = nxt(f[i][j - 1], nums2[j - 1]); f[i][j] = min(x, y); } } return f[m][n]; } };
3,269
Constructing Two Increasing Arrays
Hard
<p>Given 2 integer arrays <code>nums1</code> and <code>nums2</code> consisting only of 0 and 1, your task is to calculate the <strong>minimum</strong> possible <strong>largest</strong> number in arrays <code>nums1</code> and <code>nums2</code>, after doing the following.</p> <p>Replace every 0 with an <em>even positive integer</em> and every 1 with an <em>odd positive integer</em>. After replacement, both arrays should be <strong>increasing</strong> and each integer should be used <strong>at most</strong> once.</p> <p>Return the <em>minimum possible largest number</em> after applying the changes.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums1 = [], nums2 = [1,0,1,1]</span></p> <p><strong>Output:</strong> <span class="example-io">5</span></p> <p><strong>Explanation:</strong></p> <p>After replacing, <code>nums1 = []</code>, and <code>nums2 = [1, 2, 3, 5]</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums1 = [0,1,0,1], nums2 = [1,0,0,1]</span></p> <p><strong>Output:</strong> <span class="example-io">9</span></p> <p><strong>Explanation:</strong></p> <p>One way to replace, having 9 as the largest element is <code>nums1 = [2, 3, 8, 9]</code>, and <code>nums2 = [1, 4, 6, 7]</code>.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums1 = [0,1,0,0,1], nums2 = [0,0,0,1]</span></p> <p><strong>Output:</strong> <span class="example-io">13</span></p> <p><strong>Explanation:</strong></p> <p>One way to replace, having 13 as the largest element is <code>nums1 = [2, 3, 4, 6, 7]</code>, and <code>nums2 = [8, 10, 12, 13]</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>0 &lt;= nums1.length &lt;= 1000</code></li> <li><code>1 &lt;= nums2.length &lt;= 1000</code></li> <li><code>nums1</code> and <code>nums2</code> consist only of 0 and 1.</li> </ul>
Array; Dynamic Programming
Go
func minLargest(nums1 []int, nums2 []int) int { m, n := len(nums1), len(nums2) f := make([][]int, m+1) for i := range f { f[i] = make([]int, n+1) } nxt := func(x, y int) int { if (x&1 ^ y) == 1 { return x + 1 } return x + 2 } for i := 1; i <= m; i++ { f[i][0] = nxt(f[i-1][0], nums1[i-1]) } for j := 1; j <= n; j++ { f[0][j] = nxt(f[0][j-1], nums2[j-1]) } for i := 1; i <= m; i++ { for j := 1; j <= n; j++ { x := nxt(f[i-1][j], nums1[i-1]) y := nxt(f[i][j-1], nums2[j-1]) f[i][j] = min(x, y) } } return f[m][n] }
3,269
Constructing Two Increasing Arrays
Hard
<p>Given 2 integer arrays <code>nums1</code> and <code>nums2</code> consisting only of 0 and 1, your task is to calculate the <strong>minimum</strong> possible <strong>largest</strong> number in arrays <code>nums1</code> and <code>nums2</code>, after doing the following.</p> <p>Replace every 0 with an <em>even positive integer</em> and every 1 with an <em>odd positive integer</em>. After replacement, both arrays should be <strong>increasing</strong> and each integer should be used <strong>at most</strong> once.</p> <p>Return the <em>minimum possible largest number</em> after applying the changes.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums1 = [], nums2 = [1,0,1,1]</span></p> <p><strong>Output:</strong> <span class="example-io">5</span></p> <p><strong>Explanation:</strong></p> <p>After replacing, <code>nums1 = []</code>, and <code>nums2 = [1, 2, 3, 5]</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums1 = [0,1,0,1], nums2 = [1,0,0,1]</span></p> <p><strong>Output:</strong> <span class="example-io">9</span></p> <p><strong>Explanation:</strong></p> <p>One way to replace, having 9 as the largest element is <code>nums1 = [2, 3, 8, 9]</code>, and <code>nums2 = [1, 4, 6, 7]</code>.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums1 = [0,1,0,0,1], nums2 = [0,0,0,1]</span></p> <p><strong>Output:</strong> <span class="example-io">13</span></p> <p><strong>Explanation:</strong></p> <p>One way to replace, having 13 as the largest element is <code>nums1 = [2, 3, 4, 6, 7]</code>, and <code>nums2 = [8, 10, 12, 13]</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>0 &lt;= nums1.length &lt;= 1000</code></li> <li><code>1 &lt;= nums2.length &lt;= 1000</code></li> <li><code>nums1</code> and <code>nums2</code> consist only of 0 and 1.</li> </ul>
Array; Dynamic Programming
Java
class Solution { public int minLargest(int[] nums1, int[] nums2) { int m = nums1.length, n = nums2.length; int[][] f = new int[m + 1][n + 1]; for (int i = 1; i <= m; ++i) { f[i][0] = nxt(f[i - 1][0], nums1[i - 1]); } for (int j = 1; j <= n; ++j) { f[0][j] = nxt(f[0][j - 1], nums2[j - 1]); } for (int i = 1; i <= m; ++i) { for (int j = 1; j <= n; ++j) { int x = nxt(f[i - 1][j], nums1[i - 1]); int y = nxt(f[i][j - 1], nums2[j - 1]); f[i][j] = Math.min(x, y); } } return f[m][n]; } private int nxt(int x, int y) { return (x & 1 ^ y) == 1 ? x + 1 : x + 2; } }
3,269
Constructing Two Increasing Arrays
Hard
<p>Given 2 integer arrays <code>nums1</code> and <code>nums2</code> consisting only of 0 and 1, your task is to calculate the <strong>minimum</strong> possible <strong>largest</strong> number in arrays <code>nums1</code> and <code>nums2</code>, after doing the following.</p> <p>Replace every 0 with an <em>even positive integer</em> and every 1 with an <em>odd positive integer</em>. After replacement, both arrays should be <strong>increasing</strong> and each integer should be used <strong>at most</strong> once.</p> <p>Return the <em>minimum possible largest number</em> after applying the changes.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums1 = [], nums2 = [1,0,1,1]</span></p> <p><strong>Output:</strong> <span class="example-io">5</span></p> <p><strong>Explanation:</strong></p> <p>After replacing, <code>nums1 = []</code>, and <code>nums2 = [1, 2, 3, 5]</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums1 = [0,1,0,1], nums2 = [1,0,0,1]</span></p> <p><strong>Output:</strong> <span class="example-io">9</span></p> <p><strong>Explanation:</strong></p> <p>One way to replace, having 9 as the largest element is <code>nums1 = [2, 3, 8, 9]</code>, and <code>nums2 = [1, 4, 6, 7]</code>.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums1 = [0,1,0,0,1], nums2 = [0,0,0,1]</span></p> <p><strong>Output:</strong> <span class="example-io">13</span></p> <p><strong>Explanation:</strong></p> <p>One way to replace, having 13 as the largest element is <code>nums1 = [2, 3, 4, 6, 7]</code>, and <code>nums2 = [8, 10, 12, 13]</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>0 &lt;= nums1.length &lt;= 1000</code></li> <li><code>1 &lt;= nums2.length &lt;= 1000</code></li> <li><code>nums1</code> and <code>nums2</code> consist only of 0 and 1.</li> </ul>
Array; Dynamic Programming
Python
class Solution: def minLargest(self, nums1: List[int], nums2: List[int]) -> int: def nxt(x: int, y: int) -> int: return x + 1 if (x & 1 ^ y) == 1 else x + 2 m, n = len(nums1), len(nums2) f = [[0] * (n + 1) for _ in range(m + 1)] for i, x in enumerate(nums1, 1): f[i][0] = nxt(f[i - 1][0], x) for j, y in enumerate(nums2, 1): f[0][j] = nxt(f[0][j - 1], y) for i, x in enumerate(nums1, 1): for j, y in enumerate(nums2, 1): f[i][j] = min(nxt(f[i - 1][j], x), nxt(f[i][j - 1], y)) return f[m][n]
3,269
Constructing Two Increasing Arrays
Hard
<p>Given 2 integer arrays <code>nums1</code> and <code>nums2</code> consisting only of 0 and 1, your task is to calculate the <strong>minimum</strong> possible <strong>largest</strong> number in arrays <code>nums1</code> and <code>nums2</code>, after doing the following.</p> <p>Replace every 0 with an <em>even positive integer</em> and every 1 with an <em>odd positive integer</em>. After replacement, both arrays should be <strong>increasing</strong> and each integer should be used <strong>at most</strong> once.</p> <p>Return the <em>minimum possible largest number</em> after applying the changes.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums1 = [], nums2 = [1,0,1,1]</span></p> <p><strong>Output:</strong> <span class="example-io">5</span></p> <p><strong>Explanation:</strong></p> <p>After replacing, <code>nums1 = []</code>, and <code>nums2 = [1, 2, 3, 5]</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums1 = [0,1,0,1], nums2 = [1,0,0,1]</span></p> <p><strong>Output:</strong> <span class="example-io">9</span></p> <p><strong>Explanation:</strong></p> <p>One way to replace, having 9 as the largest element is <code>nums1 = [2, 3, 8, 9]</code>, and <code>nums2 = [1, 4, 6, 7]</code>.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums1 = [0,1,0,0,1], nums2 = [0,0,0,1]</span></p> <p><strong>Output:</strong> <span class="example-io">13</span></p> <p><strong>Explanation:</strong></p> <p>One way to replace, having 13 as the largest element is <code>nums1 = [2, 3, 4, 6, 7]</code>, and <code>nums2 = [8, 10, 12, 13]</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>0 &lt;= nums1.length &lt;= 1000</code></li> <li><code>1 &lt;= nums2.length &lt;= 1000</code></li> <li><code>nums1</code> and <code>nums2</code> consist only of 0 and 1.</li> </ul>
Array; Dynamic Programming
TypeScript
function minLargest(nums1: number[], nums2: number[]): number { const m = nums1.length; const n = nums2.length; const f: number[][] = Array.from({ length: m + 1 }, () => Array(n + 1).fill(0)); const nxt = (x: number, y: number): number => { return (x & 1) ^ y ? x + 1 : x + 2; }; for (let i = 1; i <= m; ++i) { f[i][0] = nxt(f[i - 1][0], nums1[i - 1]); } for (let j = 1; j <= n; ++j) { f[0][j] = nxt(f[0][j - 1], nums2[j - 1]); } for (let i = 1; i <= m; ++i) { for (let j = 1; j <= n; ++j) { f[i][j] = Math.min(nxt(f[i - 1][j], nums1[i - 1]), nxt(f[i][j - 1], nums2[j - 1])); } } return f[m][n]; }
3,270
Find the Key of the Numbers
Easy
<p>You are given three <strong>positive</strong> integers <code>num1</code>, <code>num2</code>, and <code>num3</code>.</p> <p>The <code>key</code> of <code>num1</code>, <code>num2</code>, and <code>num3</code> is defined as a four-digit number such that:</p> <ul> <li>Initially, if any number has <strong>less than</strong> four digits, it is padded with <strong>leading zeros</strong>.</li> <li>The <code>i<sup>th</sup></code> digit (<code>1 &lt;= i &lt;= 4</code>) of the <code>key</code> is generated by taking the <strong>smallest</strong> digit among the <code>i<sup>th</sup></code> digits of <code>num1</code>, <code>num2</code>, and <code>num3</code>.</li> </ul> <p>Return the <code>key</code> of the three numbers <strong>without</strong> leading zeros (<em>if any</em>).</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">num1 = 1, num2 = 10, num3 = 1000</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>On padding, <code>num1</code> becomes <code>&quot;0001&quot;</code>, <code>num2</code> becomes <code>&quot;0010&quot;</code>, and <code>num3</code> remains <code>&quot;1000&quot;</code>.</p> <ul> <li>The <code>1<sup>st</sup></code> digit of the <code>key</code> is <code>min(0, 0, 1)</code>.</li> <li>The <code>2<sup>nd</sup></code> digit of the <code>key</code> is <code>min(0, 0, 0)</code>.</li> <li>The <code>3<sup>rd</sup></code> digit of the <code>key</code> is <code>min(0, 1, 0)</code>.</li> <li>The <code>4<sup>th</sup></code> digit of the <code>key</code> is <code>min(1, 0, 0)</code>.</li> </ul> <p>Hence, the <code>key</code> is <code>&quot;0000&quot;</code>, i.e. 0.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">num1 = 987, num2 = 879, num3 = 798</span></p> <p><strong>Output:</strong> <span class="example-io">777</span></p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">num1 = 1, num2 = 2, num3 = 3</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= num1, num2, num3 &lt;= 9999</code></li> </ul>
Math
C++
class Solution { public: int generateKey(int num1, int num2, int num3) { int ans = 0, k = 1; for (int i = 0; i < 4; ++i) { int x = min({num1 / k % 10, num2 / k % 10, num3 / k % 10}); ans += x * k; k *= 10; } return ans; } };
3,270
Find the Key of the Numbers
Easy
<p>You are given three <strong>positive</strong> integers <code>num1</code>, <code>num2</code>, and <code>num3</code>.</p> <p>The <code>key</code> of <code>num1</code>, <code>num2</code>, and <code>num3</code> is defined as a four-digit number such that:</p> <ul> <li>Initially, if any number has <strong>less than</strong> four digits, it is padded with <strong>leading zeros</strong>.</li> <li>The <code>i<sup>th</sup></code> digit (<code>1 &lt;= i &lt;= 4</code>) of the <code>key</code> is generated by taking the <strong>smallest</strong> digit among the <code>i<sup>th</sup></code> digits of <code>num1</code>, <code>num2</code>, and <code>num3</code>.</li> </ul> <p>Return the <code>key</code> of the three numbers <strong>without</strong> leading zeros (<em>if any</em>).</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">num1 = 1, num2 = 10, num3 = 1000</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>On padding, <code>num1</code> becomes <code>&quot;0001&quot;</code>, <code>num2</code> becomes <code>&quot;0010&quot;</code>, and <code>num3</code> remains <code>&quot;1000&quot;</code>.</p> <ul> <li>The <code>1<sup>st</sup></code> digit of the <code>key</code> is <code>min(0, 0, 1)</code>.</li> <li>The <code>2<sup>nd</sup></code> digit of the <code>key</code> is <code>min(0, 0, 0)</code>.</li> <li>The <code>3<sup>rd</sup></code> digit of the <code>key</code> is <code>min(0, 1, 0)</code>.</li> <li>The <code>4<sup>th</sup></code> digit of the <code>key</code> is <code>min(1, 0, 0)</code>.</li> </ul> <p>Hence, the <code>key</code> is <code>&quot;0000&quot;</code>, i.e. 0.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">num1 = 987, num2 = 879, num3 = 798</span></p> <p><strong>Output:</strong> <span class="example-io">777</span></p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">num1 = 1, num2 = 2, num3 = 3</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= num1, num2, num3 &lt;= 9999</code></li> </ul>
Math
Go
func generateKey(num1 int, num2 int, num3 int) (ans int) { k := 1 for i := 0; i < 4; i++ { x := min(min(num1/k%10, num2/k%10), num3/k%10) ans += x * k k *= 10 } return }
3,270
Find the Key of the Numbers
Easy
<p>You are given three <strong>positive</strong> integers <code>num1</code>, <code>num2</code>, and <code>num3</code>.</p> <p>The <code>key</code> of <code>num1</code>, <code>num2</code>, and <code>num3</code> is defined as a four-digit number such that:</p> <ul> <li>Initially, if any number has <strong>less than</strong> four digits, it is padded with <strong>leading zeros</strong>.</li> <li>The <code>i<sup>th</sup></code> digit (<code>1 &lt;= i &lt;= 4</code>) of the <code>key</code> is generated by taking the <strong>smallest</strong> digit among the <code>i<sup>th</sup></code> digits of <code>num1</code>, <code>num2</code>, and <code>num3</code>.</li> </ul> <p>Return the <code>key</code> of the three numbers <strong>without</strong> leading zeros (<em>if any</em>).</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">num1 = 1, num2 = 10, num3 = 1000</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>On padding, <code>num1</code> becomes <code>&quot;0001&quot;</code>, <code>num2</code> becomes <code>&quot;0010&quot;</code>, and <code>num3</code> remains <code>&quot;1000&quot;</code>.</p> <ul> <li>The <code>1<sup>st</sup></code> digit of the <code>key</code> is <code>min(0, 0, 1)</code>.</li> <li>The <code>2<sup>nd</sup></code> digit of the <code>key</code> is <code>min(0, 0, 0)</code>.</li> <li>The <code>3<sup>rd</sup></code> digit of the <code>key</code> is <code>min(0, 1, 0)</code>.</li> <li>The <code>4<sup>th</sup></code> digit of the <code>key</code> is <code>min(1, 0, 0)</code>.</li> </ul> <p>Hence, the <code>key</code> is <code>&quot;0000&quot;</code>, i.e. 0.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">num1 = 987, num2 = 879, num3 = 798</span></p> <p><strong>Output:</strong> <span class="example-io">777</span></p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">num1 = 1, num2 = 2, num3 = 3</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= num1, num2, num3 &lt;= 9999</code></li> </ul>
Math
Java
class Solution { public int generateKey(int num1, int num2, int num3) { int ans = 0, k = 1; for (int i = 0; i < 4; ++i) { int x = Math.min(Math.min(num1 / k % 10, num2 / k % 10), num3 / k % 10); ans += x * k; k *= 10; } return ans; } }
3,270
Find the Key of the Numbers
Easy
<p>You are given three <strong>positive</strong> integers <code>num1</code>, <code>num2</code>, and <code>num3</code>.</p> <p>The <code>key</code> of <code>num1</code>, <code>num2</code>, and <code>num3</code> is defined as a four-digit number such that:</p> <ul> <li>Initially, if any number has <strong>less than</strong> four digits, it is padded with <strong>leading zeros</strong>.</li> <li>The <code>i<sup>th</sup></code> digit (<code>1 &lt;= i &lt;= 4</code>) of the <code>key</code> is generated by taking the <strong>smallest</strong> digit among the <code>i<sup>th</sup></code> digits of <code>num1</code>, <code>num2</code>, and <code>num3</code>.</li> </ul> <p>Return the <code>key</code> of the three numbers <strong>without</strong> leading zeros (<em>if any</em>).</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">num1 = 1, num2 = 10, num3 = 1000</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>On padding, <code>num1</code> becomes <code>&quot;0001&quot;</code>, <code>num2</code> becomes <code>&quot;0010&quot;</code>, and <code>num3</code> remains <code>&quot;1000&quot;</code>.</p> <ul> <li>The <code>1<sup>st</sup></code> digit of the <code>key</code> is <code>min(0, 0, 1)</code>.</li> <li>The <code>2<sup>nd</sup></code> digit of the <code>key</code> is <code>min(0, 0, 0)</code>.</li> <li>The <code>3<sup>rd</sup></code> digit of the <code>key</code> is <code>min(0, 1, 0)</code>.</li> <li>The <code>4<sup>th</sup></code> digit of the <code>key</code> is <code>min(1, 0, 0)</code>.</li> </ul> <p>Hence, the <code>key</code> is <code>&quot;0000&quot;</code>, i.e. 0.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">num1 = 987, num2 = 879, num3 = 798</span></p> <p><strong>Output:</strong> <span class="example-io">777</span></p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">num1 = 1, num2 = 2, num3 = 3</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= num1, num2, num3 &lt;= 9999</code></li> </ul>
Math
Python
class Solution: def generateKey(self, num1: int, num2: int, num3: int) -> int: ans, k = 0, 1 for _ in range(4): x = min(num1 // k % 10, num2 // k % 10, num3 // k % 10) ans += x * k k *= 10 return ans
3,270
Find the Key of the Numbers
Easy
<p>You are given three <strong>positive</strong> integers <code>num1</code>, <code>num2</code>, and <code>num3</code>.</p> <p>The <code>key</code> of <code>num1</code>, <code>num2</code>, and <code>num3</code> is defined as a four-digit number such that:</p> <ul> <li>Initially, if any number has <strong>less than</strong> four digits, it is padded with <strong>leading zeros</strong>.</li> <li>The <code>i<sup>th</sup></code> digit (<code>1 &lt;= i &lt;= 4</code>) of the <code>key</code> is generated by taking the <strong>smallest</strong> digit among the <code>i<sup>th</sup></code> digits of <code>num1</code>, <code>num2</code>, and <code>num3</code>.</li> </ul> <p>Return the <code>key</code> of the three numbers <strong>without</strong> leading zeros (<em>if any</em>).</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">num1 = 1, num2 = 10, num3 = 1000</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>On padding, <code>num1</code> becomes <code>&quot;0001&quot;</code>, <code>num2</code> becomes <code>&quot;0010&quot;</code>, and <code>num3</code> remains <code>&quot;1000&quot;</code>.</p> <ul> <li>The <code>1<sup>st</sup></code> digit of the <code>key</code> is <code>min(0, 0, 1)</code>.</li> <li>The <code>2<sup>nd</sup></code> digit of the <code>key</code> is <code>min(0, 0, 0)</code>.</li> <li>The <code>3<sup>rd</sup></code> digit of the <code>key</code> is <code>min(0, 1, 0)</code>.</li> <li>The <code>4<sup>th</sup></code> digit of the <code>key</code> is <code>min(1, 0, 0)</code>.</li> </ul> <p>Hence, the <code>key</code> is <code>&quot;0000&quot;</code>, i.e. 0.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">num1 = 987, num2 = 879, num3 = 798</span></p> <p><strong>Output:</strong> <span class="example-io">777</span></p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">num1 = 1, num2 = 2, num3 = 3</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= num1, num2, num3 &lt;= 9999</code></li> </ul>
Math
TypeScript
function generateKey(num1: number, num2: number, num3: number): number { let [ans, k] = [0, 1]; for (let i = 0; i < 4; ++i) { const x = Math.min(((num1 / k) | 0) % 10, ((num2 / k) | 0) % 10, ((num3 / k) | 0) % 10); ans += x * k; k *= 10; } return ans; }
3,271
Hash Divided String
Medium
<p>You are given a string <code>s</code> of length <code>n</code> and an integer <code>k</code>, where <code>n</code> is a <strong>multiple</strong> of <code>k</code>. Your task is to hash the string <code>s</code> into a new string called <code>result</code>, which has a length of <code>n / k</code>.</p> <p>First, divide <code>s</code> into <code>n / k</code> <strong><span data-keyword="substring-nonempty">substrings</span></strong>, each with a length of <code>k</code>. Then, initialize <code>result</code> as an <strong>empty</strong> string.</p> <p>For each <strong>substring</strong> in order from the beginning:</p> <ul> <li>The <strong>hash value</strong> of a character is the index of that characte<!-- notionvc: 4b67483a-fa95-40b6-870d-2eacd9bc18d8 -->r in the <strong>English alphabet</strong> (e.g., <code>&#39;a&#39; &rarr;<!-- notionvc: d3f8e4c2-23cd-41ad-a14b-101dfe4c5aba --> 0</code>, <code>&#39;b&#39; &rarr;<!-- notionvc: d3f8e4c2-23cd-41ad-a14b-101dfe4c5aba --> 1</code>, ..., <code>&#39;z&#39; &rarr;<!-- notionvc: d3f8e4c2-23cd-41ad-a14b-101dfe4c5aba --> 25</code>).</li> <li>Calculate the <em>sum</em> of all the <strong>hash values</strong> of the characters in the substring.</li> <li>Find the remainder of this sum when divided by 26, which is called <code>hashedChar</code>.</li> <li>Identify the character in the English lowercase alphabet that corresponds to <code>hashedChar</code>.</li> <li>Append that character to the end of <code>result</code>.</li> </ul> <p>Return <code>result</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;abcd&quot;, k = 2</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;bf&quot;</span></p> <p><strong>Explanation:</strong></p> <p>First substring: <code>&quot;ab&quot;</code>, <code>0 + 1 = 1</code>, <code>1 % 26 = 1</code>, <code>result[0] = &#39;b&#39;</code>.</p> <p>Second substring: <code>&quot;cd&quot;</code>, <code>2 + 3 = 5</code>, <code>5 % 26 = 5</code>, <code>result[1] = &#39;f&#39;</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;mxz&quot;, k = 3</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;i&quot;</span></p> <p><strong>Explanation:</strong></p> <p>The only substring: <code>&quot;mxz&quot;</code>, <code>12 + 23 + 25 = 60</code>, <code>60 % 26 = 8</code>, <code>result[0] = &#39;i&#39;</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= k &lt;= 100</code></li> <li><code>k &lt;= s.length &lt;= 1000</code></li> <li><code>s.length</code> is divisible by <code>k</code>.</li> <li><code>s</code> consists only of lowercase English letters.</li> </ul>
String; Simulation
C++
class Solution { public: string stringHash(string s, int k) { string ans; int n = s.length(); for (int i = 0; i < n; i += k) { int t = 0; for (int j = i; j < i + k; ++j) { t += s[j] - 'a'; } int hashedChar = t % 26; ans += ('a' + hashedChar); } return ans; } };
3,271
Hash Divided String
Medium
<p>You are given a string <code>s</code> of length <code>n</code> and an integer <code>k</code>, where <code>n</code> is a <strong>multiple</strong> of <code>k</code>. Your task is to hash the string <code>s</code> into a new string called <code>result</code>, which has a length of <code>n / k</code>.</p> <p>First, divide <code>s</code> into <code>n / k</code> <strong><span data-keyword="substring-nonempty">substrings</span></strong>, each with a length of <code>k</code>. Then, initialize <code>result</code> as an <strong>empty</strong> string.</p> <p>For each <strong>substring</strong> in order from the beginning:</p> <ul> <li>The <strong>hash value</strong> of a character is the index of that characte<!-- notionvc: 4b67483a-fa95-40b6-870d-2eacd9bc18d8 -->r in the <strong>English alphabet</strong> (e.g., <code>&#39;a&#39; &rarr;<!-- notionvc: d3f8e4c2-23cd-41ad-a14b-101dfe4c5aba --> 0</code>, <code>&#39;b&#39; &rarr;<!-- notionvc: d3f8e4c2-23cd-41ad-a14b-101dfe4c5aba --> 1</code>, ..., <code>&#39;z&#39; &rarr;<!-- notionvc: d3f8e4c2-23cd-41ad-a14b-101dfe4c5aba --> 25</code>).</li> <li>Calculate the <em>sum</em> of all the <strong>hash values</strong> of the characters in the substring.</li> <li>Find the remainder of this sum when divided by 26, which is called <code>hashedChar</code>.</li> <li>Identify the character in the English lowercase alphabet that corresponds to <code>hashedChar</code>.</li> <li>Append that character to the end of <code>result</code>.</li> </ul> <p>Return <code>result</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;abcd&quot;, k = 2</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;bf&quot;</span></p> <p><strong>Explanation:</strong></p> <p>First substring: <code>&quot;ab&quot;</code>, <code>0 + 1 = 1</code>, <code>1 % 26 = 1</code>, <code>result[0] = &#39;b&#39;</code>.</p> <p>Second substring: <code>&quot;cd&quot;</code>, <code>2 + 3 = 5</code>, <code>5 % 26 = 5</code>, <code>result[1] = &#39;f&#39;</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;mxz&quot;, k = 3</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;i&quot;</span></p> <p><strong>Explanation:</strong></p> <p>The only substring: <code>&quot;mxz&quot;</code>, <code>12 + 23 + 25 = 60</code>, <code>60 % 26 = 8</code>, <code>result[0] = &#39;i&#39;</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= k &lt;= 100</code></li> <li><code>k &lt;= s.length &lt;= 1000</code></li> <li><code>s.length</code> is divisible by <code>k</code>.</li> <li><code>s</code> consists only of lowercase English letters.</li> </ul>
String; Simulation
Go
func stringHash(s string, k int) string { n := len(s) ans := make([]byte, 0, n/k) for i := 0; i < n; i += k { t := 0 for j := i; j < i+k; j++ { t += int(s[j] - 'a') } hashedChar := t % 26 ans = append(ans, 'a'+byte(hashedChar)) } return string(ans) }
3,271
Hash Divided String
Medium
<p>You are given a string <code>s</code> of length <code>n</code> and an integer <code>k</code>, where <code>n</code> is a <strong>multiple</strong> of <code>k</code>. Your task is to hash the string <code>s</code> into a new string called <code>result</code>, which has a length of <code>n / k</code>.</p> <p>First, divide <code>s</code> into <code>n / k</code> <strong><span data-keyword="substring-nonempty">substrings</span></strong>, each with a length of <code>k</code>. Then, initialize <code>result</code> as an <strong>empty</strong> string.</p> <p>For each <strong>substring</strong> in order from the beginning:</p> <ul> <li>The <strong>hash value</strong> of a character is the index of that characte<!-- notionvc: 4b67483a-fa95-40b6-870d-2eacd9bc18d8 -->r in the <strong>English alphabet</strong> (e.g., <code>&#39;a&#39; &rarr;<!-- notionvc: d3f8e4c2-23cd-41ad-a14b-101dfe4c5aba --> 0</code>, <code>&#39;b&#39; &rarr;<!-- notionvc: d3f8e4c2-23cd-41ad-a14b-101dfe4c5aba --> 1</code>, ..., <code>&#39;z&#39; &rarr;<!-- notionvc: d3f8e4c2-23cd-41ad-a14b-101dfe4c5aba --> 25</code>).</li> <li>Calculate the <em>sum</em> of all the <strong>hash values</strong> of the characters in the substring.</li> <li>Find the remainder of this sum when divided by 26, which is called <code>hashedChar</code>.</li> <li>Identify the character in the English lowercase alphabet that corresponds to <code>hashedChar</code>.</li> <li>Append that character to the end of <code>result</code>.</li> </ul> <p>Return <code>result</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;abcd&quot;, k = 2</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;bf&quot;</span></p> <p><strong>Explanation:</strong></p> <p>First substring: <code>&quot;ab&quot;</code>, <code>0 + 1 = 1</code>, <code>1 % 26 = 1</code>, <code>result[0] = &#39;b&#39;</code>.</p> <p>Second substring: <code>&quot;cd&quot;</code>, <code>2 + 3 = 5</code>, <code>5 % 26 = 5</code>, <code>result[1] = &#39;f&#39;</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;mxz&quot;, k = 3</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;i&quot;</span></p> <p><strong>Explanation:</strong></p> <p>The only substring: <code>&quot;mxz&quot;</code>, <code>12 + 23 + 25 = 60</code>, <code>60 % 26 = 8</code>, <code>result[0] = &#39;i&#39;</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= k &lt;= 100</code></li> <li><code>k &lt;= s.length &lt;= 1000</code></li> <li><code>s.length</code> is divisible by <code>k</code>.</li> <li><code>s</code> consists only of lowercase English letters.</li> </ul>
String; Simulation
Java
class Solution { public String stringHash(String s, int k) { StringBuilder ans = new StringBuilder(); int n = s.length(); for (int i = 0; i < n; i += k) { int t = 0; for (int j = i; j < i + k; ++j) { t += s.charAt(j) - 'a'; } int hashedChar = t % 26; ans.append((char) ('a' + hashedChar)); } return ans.toString(); } }
3,271
Hash Divided String
Medium
<p>You are given a string <code>s</code> of length <code>n</code> and an integer <code>k</code>, where <code>n</code> is a <strong>multiple</strong> of <code>k</code>. Your task is to hash the string <code>s</code> into a new string called <code>result</code>, which has a length of <code>n / k</code>.</p> <p>First, divide <code>s</code> into <code>n / k</code> <strong><span data-keyword="substring-nonempty">substrings</span></strong>, each with a length of <code>k</code>. Then, initialize <code>result</code> as an <strong>empty</strong> string.</p> <p>For each <strong>substring</strong> in order from the beginning:</p> <ul> <li>The <strong>hash value</strong> of a character is the index of that characte<!-- notionvc: 4b67483a-fa95-40b6-870d-2eacd9bc18d8 -->r in the <strong>English alphabet</strong> (e.g., <code>&#39;a&#39; &rarr;<!-- notionvc: d3f8e4c2-23cd-41ad-a14b-101dfe4c5aba --> 0</code>, <code>&#39;b&#39; &rarr;<!-- notionvc: d3f8e4c2-23cd-41ad-a14b-101dfe4c5aba --> 1</code>, ..., <code>&#39;z&#39; &rarr;<!-- notionvc: d3f8e4c2-23cd-41ad-a14b-101dfe4c5aba --> 25</code>).</li> <li>Calculate the <em>sum</em> of all the <strong>hash values</strong> of the characters in the substring.</li> <li>Find the remainder of this sum when divided by 26, which is called <code>hashedChar</code>.</li> <li>Identify the character in the English lowercase alphabet that corresponds to <code>hashedChar</code>.</li> <li>Append that character to the end of <code>result</code>.</li> </ul> <p>Return <code>result</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;abcd&quot;, k = 2</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;bf&quot;</span></p> <p><strong>Explanation:</strong></p> <p>First substring: <code>&quot;ab&quot;</code>, <code>0 + 1 = 1</code>, <code>1 % 26 = 1</code>, <code>result[0] = &#39;b&#39;</code>.</p> <p>Second substring: <code>&quot;cd&quot;</code>, <code>2 + 3 = 5</code>, <code>5 % 26 = 5</code>, <code>result[1] = &#39;f&#39;</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;mxz&quot;, k = 3</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;i&quot;</span></p> <p><strong>Explanation:</strong></p> <p>The only substring: <code>&quot;mxz&quot;</code>, <code>12 + 23 + 25 = 60</code>, <code>60 % 26 = 8</code>, <code>result[0] = &#39;i&#39;</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= k &lt;= 100</code></li> <li><code>k &lt;= s.length &lt;= 1000</code></li> <li><code>s.length</code> is divisible by <code>k</code>.</li> <li><code>s</code> consists only of lowercase English letters.</li> </ul>
String; Simulation
Python
class Solution: def stringHash(self, s: str, k: int) -> str: ans = [] for i in range(0, len(s), k): t = 0 for j in range(i, i + k): t += ord(s[j]) - ord("a") hashedChar = t % 26 ans.append(chr(ord("a") + hashedChar)) return "".join(ans)
3,271
Hash Divided String
Medium
<p>You are given a string <code>s</code> of length <code>n</code> and an integer <code>k</code>, where <code>n</code> is a <strong>multiple</strong> of <code>k</code>. Your task is to hash the string <code>s</code> into a new string called <code>result</code>, which has a length of <code>n / k</code>.</p> <p>First, divide <code>s</code> into <code>n / k</code> <strong><span data-keyword="substring-nonempty">substrings</span></strong>, each with a length of <code>k</code>. Then, initialize <code>result</code> as an <strong>empty</strong> string.</p> <p>For each <strong>substring</strong> in order from the beginning:</p> <ul> <li>The <strong>hash value</strong> of a character is the index of that characte<!-- notionvc: 4b67483a-fa95-40b6-870d-2eacd9bc18d8 -->r in the <strong>English alphabet</strong> (e.g., <code>&#39;a&#39; &rarr;<!-- notionvc: d3f8e4c2-23cd-41ad-a14b-101dfe4c5aba --> 0</code>, <code>&#39;b&#39; &rarr;<!-- notionvc: d3f8e4c2-23cd-41ad-a14b-101dfe4c5aba --> 1</code>, ..., <code>&#39;z&#39; &rarr;<!-- notionvc: d3f8e4c2-23cd-41ad-a14b-101dfe4c5aba --> 25</code>).</li> <li>Calculate the <em>sum</em> of all the <strong>hash values</strong> of the characters in the substring.</li> <li>Find the remainder of this sum when divided by 26, which is called <code>hashedChar</code>.</li> <li>Identify the character in the English lowercase alphabet that corresponds to <code>hashedChar</code>.</li> <li>Append that character to the end of <code>result</code>.</li> </ul> <p>Return <code>result</code>.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;abcd&quot;, k = 2</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;bf&quot;</span></p> <p><strong>Explanation:</strong></p> <p>First substring: <code>&quot;ab&quot;</code>, <code>0 + 1 = 1</code>, <code>1 % 26 = 1</code>, <code>result[0] = &#39;b&#39;</code>.</p> <p>Second substring: <code>&quot;cd&quot;</code>, <code>2 + 3 = 5</code>, <code>5 % 26 = 5</code>, <code>result[1] = &#39;f&#39;</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">s = &quot;mxz&quot;, k = 3</span></p> <p><strong>Output:</strong> <span class="example-io">&quot;i&quot;</span></p> <p><strong>Explanation:</strong></p> <p>The only substring: <code>&quot;mxz&quot;</code>, <code>12 + 23 + 25 = 60</code>, <code>60 % 26 = 8</code>, <code>result[0] = &#39;i&#39;</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= k &lt;= 100</code></li> <li><code>k &lt;= s.length &lt;= 1000</code></li> <li><code>s.length</code> is divisible by <code>k</code>.</li> <li><code>s</code> consists only of lowercase English letters.</li> </ul>
String; Simulation
TypeScript
function stringHash(s: string, k: number): string { const ans: string[] = []; const n: number = s.length; for (let i = 0; i < n; i += k) { let t: number = 0; for (let j = i; j < i + k; j++) { t += s.charCodeAt(j) - 97; } const hashedChar: number = t % 26; ans.push(String.fromCharCode(97 + hashedChar)); } return ans.join(''); }
3,272
Find the Count of Good Integers
Hard
<p>You are given two <strong>positive</strong> integers <code>n</code> and <code>k</code>.</p> <p>An integer <code>x</code> is called <strong>k-palindromic</strong> if:</p> <ul> <li><code>x</code> is a <span data-keyword="palindrome-integer">palindrome</span>.</li> <li><code>x</code> is divisible by <code>k</code>.</li> </ul> <p>An integer is called <strong>good</strong> if its digits can be <em>rearranged</em> to form a <strong>k-palindromic</strong> integer. For example, for <code>k = 2</code>, 2020 can be rearranged to form the <em>k-palindromic</em> integer 2002, whereas 1010 cannot be rearranged to form a <em>k-palindromic</em> integer.</p> <p>Return the count of <strong>good</strong> integers containing <code>n</code> digits.</p> <p><strong>Note</strong> that <em>any</em> integer must <strong>not</strong> have leading zeros, <strong>neither</strong> before <strong>nor</strong> after rearrangement. For example, 1010 <em>cannot</em> be rearranged to form 101.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 3, k = 5</span></p> <p><strong>Output:</strong> <span class="example-io">27</span></p> <p><strong>Explanation:</strong></p> <p><em>Some</em> of the good integers are:</p> <ul> <li>551 because it can be rearranged to form 515.</li> <li>525 because it is already k-palindromic.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 1, k = 4</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>The two good integers are 4 and 8.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 5, k = 6</span></p> <p><strong>Output:</strong> <span class="example-io">2468</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n &lt;= 10</code></li> <li><code>1 &lt;= k &lt;= 9</code></li> </ul>
Hash Table; Math; Combinatorics; Enumeration
C++
class Solution { public: long long countGoodIntegers(int n, int k) { vector<long long> fac(n + 1, 1); for (int i = 1; i <= n; ++i) { fac[i] = fac[i - 1] * i; } long long ans = 0; unordered_set<string> vis; int base = pow(10, (n - 1) / 2); for (int i = base; i < base * 10; ++i) { string s = to_string(i); string rev = s; reverse(rev.begin(), rev.end()); s += rev.substr(n % 2); if (stoll(s) % k) { continue; } string t = s; sort(t.begin(), t.end()); if (vis.count(t)) { continue; } vis.insert(t); vector<int> cnt(10); for (char c : t) { cnt[c - '0']++; } long long res = (n - cnt[0]) * fac[n - 1]; for (int x : cnt) { res /= fac[x]; } ans += res; } return ans; } };
3,272
Find the Count of Good Integers
Hard
<p>You are given two <strong>positive</strong> integers <code>n</code> and <code>k</code>.</p> <p>An integer <code>x</code> is called <strong>k-palindromic</strong> if:</p> <ul> <li><code>x</code> is a <span data-keyword="palindrome-integer">palindrome</span>.</li> <li><code>x</code> is divisible by <code>k</code>.</li> </ul> <p>An integer is called <strong>good</strong> if its digits can be <em>rearranged</em> to form a <strong>k-palindromic</strong> integer. For example, for <code>k = 2</code>, 2020 can be rearranged to form the <em>k-palindromic</em> integer 2002, whereas 1010 cannot be rearranged to form a <em>k-palindromic</em> integer.</p> <p>Return the count of <strong>good</strong> integers containing <code>n</code> digits.</p> <p><strong>Note</strong> that <em>any</em> integer must <strong>not</strong> have leading zeros, <strong>neither</strong> before <strong>nor</strong> after rearrangement. For example, 1010 <em>cannot</em> be rearranged to form 101.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 3, k = 5</span></p> <p><strong>Output:</strong> <span class="example-io">27</span></p> <p><strong>Explanation:</strong></p> <p><em>Some</em> of the good integers are:</p> <ul> <li>551 because it can be rearranged to form 515.</li> <li>525 because it is already k-palindromic.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 1, k = 4</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>The two good integers are 4 and 8.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 5, k = 6</span></p> <p><strong>Output:</strong> <span class="example-io">2468</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n &lt;= 10</code></li> <li><code>1 &lt;= k &lt;= 9</code></li> </ul>
Hash Table; Math; Combinatorics; Enumeration
Go
func factorial(n int) []int64 { fac := make([]int64, n+1) fac[0] = 1 for i := 1; i <= n; i++ { fac[i] = fac[i-1] * int64(i) } return fac } func countGoodIntegers(n int, k int) (ans int64) { fac := factorial(n) vis := make(map[string]bool) base := int(math.Pow(10, float64((n-1)/2))) for i := base; i < base*10; i++ { s := strconv.Itoa(i) rev := reverseString(s) s += rev[n%2:] num, _ := strconv.ParseInt(s, 10, 64) if num%int64(k) != 0 { continue } bs := []byte(s) slices.Sort(bs) t := string(bs) if vis[t] { continue } vis[t] = true cnt := make([]int, 10) for _, c := range t { cnt[c-'0']++ } res := (int64(n) - int64(cnt[0])) * fac[n-1] for _, x := range cnt { res /= fac[x] } ans += res } return } func reverseString(s string) string { t := []byte(s) for i, j := 0, len(t)-1; i < j; i, j = i+1, j-1 { t[i], t[j] = t[j], t[i] } return string(t) }
3,272
Find the Count of Good Integers
Hard
<p>You are given two <strong>positive</strong> integers <code>n</code> and <code>k</code>.</p> <p>An integer <code>x</code> is called <strong>k-palindromic</strong> if:</p> <ul> <li><code>x</code> is a <span data-keyword="palindrome-integer">palindrome</span>.</li> <li><code>x</code> is divisible by <code>k</code>.</li> </ul> <p>An integer is called <strong>good</strong> if its digits can be <em>rearranged</em> to form a <strong>k-palindromic</strong> integer. For example, for <code>k = 2</code>, 2020 can be rearranged to form the <em>k-palindromic</em> integer 2002, whereas 1010 cannot be rearranged to form a <em>k-palindromic</em> integer.</p> <p>Return the count of <strong>good</strong> integers containing <code>n</code> digits.</p> <p><strong>Note</strong> that <em>any</em> integer must <strong>not</strong> have leading zeros, <strong>neither</strong> before <strong>nor</strong> after rearrangement. For example, 1010 <em>cannot</em> be rearranged to form 101.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 3, k = 5</span></p> <p><strong>Output:</strong> <span class="example-io">27</span></p> <p><strong>Explanation:</strong></p> <p><em>Some</em> of the good integers are:</p> <ul> <li>551 because it can be rearranged to form 515.</li> <li>525 because it is already k-palindromic.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 1, k = 4</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>The two good integers are 4 and 8.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 5, k = 6</span></p> <p><strong>Output:</strong> <span class="example-io">2468</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n &lt;= 10</code></li> <li><code>1 &lt;= k &lt;= 9</code></li> </ul>
Hash Table; Math; Combinatorics; Enumeration
Java
class Solution { public long countGoodIntegers(int n, int k) { long[] fac = new long[n + 1]; fac[0] = 1; for (int i = 1; i <= n; i++) { fac[i] = fac[i - 1] * i; } long ans = 0; Set<String> vis = new HashSet<>(); int base = (int) Math.pow(10, (n - 1) / 2); for (int i = base; i < base * 10; i++) { String s = String.valueOf(i); StringBuilder sb = new StringBuilder(s).reverse(); s += sb.substring(n % 2); if (Long.parseLong(s) % k != 0) { continue; } char[] arr = s.toCharArray(); Arrays.sort(arr); String t = new String(arr); if (vis.contains(t)) { continue; } vis.add(t); int[] cnt = new int[10]; for (char c : arr) { cnt[c - '0']++; } long res = (n - cnt[0]) * fac[n - 1]; for (int x : cnt) { res /= fac[x]; } ans += res; } return ans; } }
3,272
Find the Count of Good Integers
Hard
<p>You are given two <strong>positive</strong> integers <code>n</code> and <code>k</code>.</p> <p>An integer <code>x</code> is called <strong>k-palindromic</strong> if:</p> <ul> <li><code>x</code> is a <span data-keyword="palindrome-integer">palindrome</span>.</li> <li><code>x</code> is divisible by <code>k</code>.</li> </ul> <p>An integer is called <strong>good</strong> if its digits can be <em>rearranged</em> to form a <strong>k-palindromic</strong> integer. For example, for <code>k = 2</code>, 2020 can be rearranged to form the <em>k-palindromic</em> integer 2002, whereas 1010 cannot be rearranged to form a <em>k-palindromic</em> integer.</p> <p>Return the count of <strong>good</strong> integers containing <code>n</code> digits.</p> <p><strong>Note</strong> that <em>any</em> integer must <strong>not</strong> have leading zeros, <strong>neither</strong> before <strong>nor</strong> after rearrangement. For example, 1010 <em>cannot</em> be rearranged to form 101.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 3, k = 5</span></p> <p><strong>Output:</strong> <span class="example-io">27</span></p> <p><strong>Explanation:</strong></p> <p><em>Some</em> of the good integers are:</p> <ul> <li>551 because it can be rearranged to form 515.</li> <li>525 because it is already k-palindromic.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 1, k = 4</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>The two good integers are 4 and 8.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 5, k = 6</span></p> <p><strong>Output:</strong> <span class="example-io">2468</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n &lt;= 10</code></li> <li><code>1 &lt;= k &lt;= 9</code></li> </ul>
Hash Table; Math; Combinatorics; Enumeration
JavaScript
/** * @param {number} n * @param {number} k * @return {number} */ var countGoodIntegers = function (n, k) { const fac = factorial(n); let ans = 0; const vis = new Set(); const base = Math.pow(10, Math.floor((n - 1) / 2)); for (let i = base; i < base * 10; i++) { let s = String(i); const rev = reverseString(s); if (n % 2 === 1) { s += rev.substring(1); } else { s += rev; } if (parseInt(s, 10) % k !== 0) { continue; } const bs = Array.from(s).sort(); const t = bs.join(''); if (vis.has(t)) { continue; } vis.add(t); const cnt = Array(10).fill(0); for (const c of t) { cnt[parseInt(c, 10)]++; } let res = (n - cnt[0]) * fac[n - 1]; for (const x of cnt) { res /= fac[x]; } ans += res; } return ans; }; function factorial(n) { const fac = Array(n + 1).fill(1); for (let i = 1; i <= n; i++) { fac[i] = fac[i - 1] * i; } return fac; } function reverseString(s) { return s.split('').reverse().join(''); }
3,272
Find the Count of Good Integers
Hard
<p>You are given two <strong>positive</strong> integers <code>n</code> and <code>k</code>.</p> <p>An integer <code>x</code> is called <strong>k-palindromic</strong> if:</p> <ul> <li><code>x</code> is a <span data-keyword="palindrome-integer">palindrome</span>.</li> <li><code>x</code> is divisible by <code>k</code>.</li> </ul> <p>An integer is called <strong>good</strong> if its digits can be <em>rearranged</em> to form a <strong>k-palindromic</strong> integer. For example, for <code>k = 2</code>, 2020 can be rearranged to form the <em>k-palindromic</em> integer 2002, whereas 1010 cannot be rearranged to form a <em>k-palindromic</em> integer.</p> <p>Return the count of <strong>good</strong> integers containing <code>n</code> digits.</p> <p><strong>Note</strong> that <em>any</em> integer must <strong>not</strong> have leading zeros, <strong>neither</strong> before <strong>nor</strong> after rearrangement. For example, 1010 <em>cannot</em> be rearranged to form 101.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 3, k = 5</span></p> <p><strong>Output:</strong> <span class="example-io">27</span></p> <p><strong>Explanation:</strong></p> <p><em>Some</em> of the good integers are:</p> <ul> <li>551 because it can be rearranged to form 515.</li> <li>525 because it is already k-palindromic.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 1, k = 4</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>The two good integers are 4 and 8.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 5, k = 6</span></p> <p><strong>Output:</strong> <span class="example-io">2468</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n &lt;= 10</code></li> <li><code>1 &lt;= k &lt;= 9</code></li> </ul>
Hash Table; Math; Combinatorics; Enumeration
Python
class Solution: def countGoodIntegers(self, n: int, k: int) -> int: fac = [factorial(i) for i in range(n + 1)] ans = 0 vis = set() base = 10 ** ((n - 1) // 2) for i in range(base, base * 10): s = str(i) s += s[::-1][n % 2 :] if int(s) % k: continue t = "".join(sorted(s)) if t in vis: continue vis.add(t) cnt = Counter(t) res = (n - cnt["0"]) * fac[n - 1] for x in cnt.values(): res //= fac[x] ans += res return ans
3,272
Find the Count of Good Integers
Hard
<p>You are given two <strong>positive</strong> integers <code>n</code> and <code>k</code>.</p> <p>An integer <code>x</code> is called <strong>k-palindromic</strong> if:</p> <ul> <li><code>x</code> is a <span data-keyword="palindrome-integer">palindrome</span>.</li> <li><code>x</code> is divisible by <code>k</code>.</li> </ul> <p>An integer is called <strong>good</strong> if its digits can be <em>rearranged</em> to form a <strong>k-palindromic</strong> integer. For example, for <code>k = 2</code>, 2020 can be rearranged to form the <em>k-palindromic</em> integer 2002, whereas 1010 cannot be rearranged to form a <em>k-palindromic</em> integer.</p> <p>Return the count of <strong>good</strong> integers containing <code>n</code> digits.</p> <p><strong>Note</strong> that <em>any</em> integer must <strong>not</strong> have leading zeros, <strong>neither</strong> before <strong>nor</strong> after rearrangement. For example, 1010 <em>cannot</em> be rearranged to form 101.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 3, k = 5</span></p> <p><strong>Output:</strong> <span class="example-io">27</span></p> <p><strong>Explanation:</strong></p> <p><em>Some</em> of the good integers are:</p> <ul> <li>551 because it can be rearranged to form 515.</li> <li>525 because it is already k-palindromic.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 1, k = 4</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>The two good integers are 4 and 8.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 5, k = 6</span></p> <p><strong>Output:</strong> <span class="example-io">2468</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n &lt;= 10</code></li> <li><code>1 &lt;= k &lt;= 9</code></li> </ul>
Hash Table; Math; Combinatorics; Enumeration
Rust
impl Solution { pub fn count_good_integers(n: i32, k: i32) -> i64 { use std::collections::HashSet; let n = n as usize; let k = k as i64; let mut fac = vec![1_i64; n + 1]; for i in 1..=n { fac[i] = fac[i - 1] * i as i64; } let mut ans = 0; let mut vis = HashSet::new(); let base = 10_i64.pow(((n - 1) / 2) as u32); for i in base..base * 10 { let s = i.to_string(); let rev: String = s.chars().rev().collect(); let full_s = if n % 2 == 0 { format!("{}{}", s, rev) } else { format!("{}{}", s, &rev[1..]) }; let num: i64 = full_s.parse().unwrap(); if num % k != 0 { continue; } let mut arr: Vec<char> = full_s.chars().collect(); arr.sort_unstable(); let t: String = arr.iter().collect(); if vis.contains(&t) { continue; } vis.insert(t); let mut cnt = vec![0; 10]; for c in arr { cnt[c as usize - '0' as usize] += 1; } let mut res = (n - cnt[0]) as i64 * fac[n - 1]; for &x in &cnt { if x > 0 { res /= fac[x]; } } ans += res; } ans } }
3,272
Find the Count of Good Integers
Hard
<p>You are given two <strong>positive</strong> integers <code>n</code> and <code>k</code>.</p> <p>An integer <code>x</code> is called <strong>k-palindromic</strong> if:</p> <ul> <li><code>x</code> is a <span data-keyword="palindrome-integer">palindrome</span>.</li> <li><code>x</code> is divisible by <code>k</code>.</li> </ul> <p>An integer is called <strong>good</strong> if its digits can be <em>rearranged</em> to form a <strong>k-palindromic</strong> integer. For example, for <code>k = 2</code>, 2020 can be rearranged to form the <em>k-palindromic</em> integer 2002, whereas 1010 cannot be rearranged to form a <em>k-palindromic</em> integer.</p> <p>Return the count of <strong>good</strong> integers containing <code>n</code> digits.</p> <p><strong>Note</strong> that <em>any</em> integer must <strong>not</strong> have leading zeros, <strong>neither</strong> before <strong>nor</strong> after rearrangement. For example, 1010 <em>cannot</em> be rearranged to form 101.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 3, k = 5</span></p> <p><strong>Output:</strong> <span class="example-io">27</span></p> <p><strong>Explanation:</strong></p> <p><em>Some</em> of the good integers are:</p> <ul> <li>551 because it can be rearranged to form 515.</li> <li>525 because it is already k-palindromic.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 1, k = 4</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>The two good integers are 4 and 8.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 5, k = 6</span></p> <p><strong>Output:</strong> <span class="example-io">2468</span></p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n &lt;= 10</code></li> <li><code>1 &lt;= k &lt;= 9</code></li> </ul>
Hash Table; Math; Combinatorics; Enumeration
TypeScript
function countGoodIntegers(n: number, k: number): number { const fac = factorial(n); let ans = 0; const vis = new Set<string>(); const base = Math.pow(10, Math.floor((n - 1) / 2)); for (let i = base; i < base * 10; i++) { let s = `${i}`; const rev = reverseString(s); if (n % 2 === 1) { s += rev.substring(1); } else { s += rev; } if (+s % k !== 0) { continue; } const bs = Array.from(s).sort(); const t = bs.join(''); if (vis.has(t)) { continue; } vis.add(t); const cnt = Array(10).fill(0); for (const c of t) { cnt[+c]++; } let res = (n - cnt[0]) * fac[n - 1]; for (const x of cnt) { res /= fac[x]; } ans += res; } return ans; } function factorial(n: number): number[] { const fac = Array(n + 1).fill(1); for (let i = 1; i <= n; i++) { fac[i] = fac[i - 1] * i; } return fac; } function reverseString(s: string): string { return s.split('').reverse().join(''); }
3,274
Check if Two Chessboard Squares Have the Same Color
Easy
<p>You are given two strings, <code>coordinate1</code> and <code>coordinate2</code>, representing the coordinates of a square on an <code>8 x 8</code> chessboard.</p> <p>Below is the chessboard for reference.</p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3200-3299/3274.Check%20if%20Two%20Chessboard%20Squares%20Have%20the%20Same%20Color/images/screenshot-2021-02-20-at-22159-pm.png" style="width: 400px; height: 396px;" /></p> <p>Return <code>true</code> if these two squares have the same color and <code>false</code> otherwise.</p> <p>The coordinate will always represent a valid chessboard square. The coordinate will always have the letter first (indicating its column), and the number second (indicating its row).</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">coordinate1 = &quot;a1&quot;, coordinate2 = &quot;c3&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">true</span></p> <p><strong>Explanation:</strong></p> <p>Both squares are black.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">coordinate1 = &quot;a1&quot;, coordinate2 = &quot;h3&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p>Square <code>&quot;a1&quot;</code> is black and <code>&quot;h3&quot;</code> is white.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>coordinate1.length == coordinate2.length == 2</code></li> <li><code>&#39;a&#39; &lt;= coordinate1[0], coordinate2[0] &lt;= &#39;h&#39;</code></li> <li><code>&#39;1&#39; &lt;= coordinate1[1], coordinate2[1] &lt;= &#39;8&#39;</code></li> </ul>
Math; String
C++
class Solution { public: bool checkTwoChessboards(string coordinate1, string coordinate2) { int x = coordinate1[0] - coordinate2[0]; int y = coordinate1[1] - coordinate2[1]; return (x + y) % 2 == 0; } };
3,274
Check if Two Chessboard Squares Have the Same Color
Easy
<p>You are given two strings, <code>coordinate1</code> and <code>coordinate2</code>, representing the coordinates of a square on an <code>8 x 8</code> chessboard.</p> <p>Below is the chessboard for reference.</p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3200-3299/3274.Check%20if%20Two%20Chessboard%20Squares%20Have%20the%20Same%20Color/images/screenshot-2021-02-20-at-22159-pm.png" style="width: 400px; height: 396px;" /></p> <p>Return <code>true</code> if these two squares have the same color and <code>false</code> otherwise.</p> <p>The coordinate will always represent a valid chessboard square. The coordinate will always have the letter first (indicating its column), and the number second (indicating its row).</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">coordinate1 = &quot;a1&quot;, coordinate2 = &quot;c3&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">true</span></p> <p><strong>Explanation:</strong></p> <p>Both squares are black.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">coordinate1 = &quot;a1&quot;, coordinate2 = &quot;h3&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p>Square <code>&quot;a1&quot;</code> is black and <code>&quot;h3&quot;</code> is white.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>coordinate1.length == coordinate2.length == 2</code></li> <li><code>&#39;a&#39; &lt;= coordinate1[0], coordinate2[0] &lt;= &#39;h&#39;</code></li> <li><code>&#39;1&#39; &lt;= coordinate1[1], coordinate2[1] &lt;= &#39;8&#39;</code></li> </ul>
Math; String
Go
func checkTwoChessboards(coordinate1 string, coordinate2 string) bool { x := coordinate1[0] - coordinate2[0] y := coordinate1[1] - coordinate2[1] return (x+y)%2 == 0 }