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3,133
Minimum Array End
Medium
<p>You are given two integers <code>n</code> and <code>x</code>. You have to construct an array of <strong>positive</strong> integers <code>nums</code> of size <code>n</code> where for every <code>0 &lt;= i &lt; n - 1</code>, <code>nums[i + 1]</code> is <strong>greater than</strong> <code>nums[i]</code>, and the result of the bitwise <code>AND</code> operation between all elements of <code>nums</code> is <code>x</code>.</p> <p>Return the <strong>minimum</strong> possible value of <code>nums[n - 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">n = 3, x = 4</span></p> <p><strong>Output:</strong> <span class="example-io">6</span></p> <p><strong>Explanation:</strong></p> <p><code>nums</code> can be <code>[4,5,6]</code> and its last element is 6.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 2, x = 7</span></p> <p><strong>Output:</strong> <span class="example-io">15</span></p> <p><strong>Explanation:</strong></p> <p><code>nums</code> can be <code>[7,15]</code> and its last element is 15.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n, x &lt;= 10<sup>8</sup></code></li> </ul>
Bit Manipulation
C++
class Solution { public: long long minEnd(int n, int x) { --n; long long ans = x; for (int i = 0; i < 31; ++i) { if (x >> i & 1 ^ 1) { ans |= (n & 1) << i; n >>= 1; } } ans |= (1LL * n) << 31; return ans; } };
3,133
Minimum Array End
Medium
<p>You are given two integers <code>n</code> and <code>x</code>. You have to construct an array of <strong>positive</strong> integers <code>nums</code> of size <code>n</code> where for every <code>0 &lt;= i &lt; n - 1</code>, <code>nums[i + 1]</code> is <strong>greater than</strong> <code>nums[i]</code>, and the result of the bitwise <code>AND</code> operation between all elements of <code>nums</code> is <code>x</code>.</p> <p>Return the <strong>minimum</strong> possible value of <code>nums[n - 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">n = 3, x = 4</span></p> <p><strong>Output:</strong> <span class="example-io">6</span></p> <p><strong>Explanation:</strong></p> <p><code>nums</code> can be <code>[4,5,6]</code> and its last element is 6.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 2, x = 7</span></p> <p><strong>Output:</strong> <span class="example-io">15</span></p> <p><strong>Explanation:</strong></p> <p><code>nums</code> can be <code>[7,15]</code> and its last element is 15.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n, x &lt;= 10<sup>8</sup></code></li> </ul>
Bit Manipulation
Go
func minEnd(n int, x int) (ans int64) { n-- ans = int64(x) for i := 0; i < 31; i++ { if x>>i&1 == 0 { ans |= int64((n & 1) << i) n >>= 1 } } ans |= int64(n) << 31 return }
3,133
Minimum Array End
Medium
<p>You are given two integers <code>n</code> and <code>x</code>. You have to construct an array of <strong>positive</strong> integers <code>nums</code> of size <code>n</code> where for every <code>0 &lt;= i &lt; n - 1</code>, <code>nums[i + 1]</code> is <strong>greater than</strong> <code>nums[i]</code>, and the result of the bitwise <code>AND</code> operation between all elements of <code>nums</code> is <code>x</code>.</p> <p>Return the <strong>minimum</strong> possible value of <code>nums[n - 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">n = 3, x = 4</span></p> <p><strong>Output:</strong> <span class="example-io">6</span></p> <p><strong>Explanation:</strong></p> <p><code>nums</code> can be <code>[4,5,6]</code> and its last element is 6.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 2, x = 7</span></p> <p><strong>Output:</strong> <span class="example-io">15</span></p> <p><strong>Explanation:</strong></p> <p><code>nums</code> can be <code>[7,15]</code> and its last element is 15.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n, x &lt;= 10<sup>8</sup></code></li> </ul>
Bit Manipulation
Java
class Solution { public long minEnd(int n, int x) { --n; long ans = x; for (int i = 0; i < 31; ++i) { if ((x >> i & 1) == 0) { ans |= (n & 1) << i; n >>= 1; } } ans |= (long) n << 31; return ans; } }
3,133
Minimum Array End
Medium
<p>You are given two integers <code>n</code> and <code>x</code>. You have to construct an array of <strong>positive</strong> integers <code>nums</code> of size <code>n</code> where for every <code>0 &lt;= i &lt; n - 1</code>, <code>nums[i + 1]</code> is <strong>greater than</strong> <code>nums[i]</code>, and the result of the bitwise <code>AND</code> operation between all elements of <code>nums</code> is <code>x</code>.</p> <p>Return the <strong>minimum</strong> possible value of <code>nums[n - 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">n = 3, x = 4</span></p> <p><strong>Output:</strong> <span class="example-io">6</span></p> <p><strong>Explanation:</strong></p> <p><code>nums</code> can be <code>[4,5,6]</code> and its last element is 6.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 2, x = 7</span></p> <p><strong>Output:</strong> <span class="example-io">15</span></p> <p><strong>Explanation:</strong></p> <p><code>nums</code> can be <code>[7,15]</code> and its last element is 15.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n, x &lt;= 10<sup>8</sup></code></li> </ul>
Bit Manipulation
Python
class Solution: def minEnd(self, n: int, x: int) -> int: n -= 1 ans = x for i in range(31): if x >> i & 1 ^ 1: ans |= (n & 1) << i n >>= 1 ans |= n << 31 return ans
3,133
Minimum Array End
Medium
<p>You are given two integers <code>n</code> and <code>x</code>. You have to construct an array of <strong>positive</strong> integers <code>nums</code> of size <code>n</code> where for every <code>0 &lt;= i &lt; n - 1</code>, <code>nums[i + 1]</code> is <strong>greater than</strong> <code>nums[i]</code>, and the result of the bitwise <code>AND</code> operation between all elements of <code>nums</code> is <code>x</code>.</p> <p>Return the <strong>minimum</strong> possible value of <code>nums[n - 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">n = 3, x = 4</span></p> <p><strong>Output:</strong> <span class="example-io">6</span></p> <p><strong>Explanation:</strong></p> <p><code>nums</code> can be <code>[4,5,6]</code> and its last element is 6.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">n = 2, x = 7</span></p> <p><strong>Output:</strong> <span class="example-io">15</span></p> <p><strong>Explanation:</strong></p> <p><code>nums</code> can be <code>[7,15]</code> and its last element is 15.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n, x &lt;= 10<sup>8</sup></code></li> </ul>
Bit Manipulation
TypeScript
function minEnd(n: number, x: number): number { --n; let ans: bigint = BigInt(x); for (let i = 0; i < 31; ++i) { if (((x >> i) & 1) ^ 1) { ans |= BigInt(n & 1) << BigInt(i); n >>= 1; } } ans |= BigInt(n) << BigInt(31); return Number(ans); }
3,134
Find the Median of the Uniqueness Array
Hard
<p>You are given an integer array <code>nums</code>. The <strong>uniqueness array</strong> of <code>nums</code> is the sorted array that contains the number of distinct elements of all the <span data-keyword="subarray-nonempty">subarrays</span> of <code>nums</code>. In other words, it is a sorted array consisting of <code>distinct(nums[i..j])</code>, for all <code>0 &lt;= i &lt;= j &lt; nums.length</code>.</p> <p>Here, <code>distinct(nums[i..j])</code> denotes the number of distinct elements in the subarray that starts at index <code>i</code> and ends at index <code>j</code>.</p> <p>Return the <strong>median</strong> of the <strong>uniqueness array</strong> of <code>nums</code>.</p> <p><strong>Note</strong> that the <strong>median</strong> of an array is defined as the middle element of the array when it is sorted in non-decreasing order. If there are two choices for a median, the <strong>smaller</strong> of the two values is taken.<!-- notionvc: 7e0f5178-4273-4a82-95ce-3395297921dc --></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]</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <p>The uniqueness array of <code>nums</code> is <code>[distinct(nums[0..0]), distinct(nums[1..1]), distinct(nums[2..2]), distinct(nums[0..1]), distinct(nums[1..2]), distinct(nums[0..2])]</code> which is equal to <code>[1, 1, 1, 2, 2, 3]</code>. The uniqueness array has a median of 1. Therefore, the answer is 1.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [3,4,3,4,5]</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>The uniqueness array of <code>nums</code> is <code>[1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3]</code>. The uniqueness array has a median of 2. Therefore, the answer is 2.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [4,3,5,4]</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>The uniqueness array of <code>nums</code> is <code>[1, 1, 1, 1, 2, 2, 2, 3, 3, 3]</code>. The uniqueness array has a median of 2. Therefore, the answer is 2.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>5</sup></code></li> </ul>
Array; Hash Table; Binary Search; Sliding Window
C++
class Solution { public: int medianOfUniquenessArray(vector<int>& nums) { int n = nums.size(); using ll = long long; ll m = (1LL + n) * n / 2; int l = 0, r = n; auto check = [&](int mx) -> bool { unordered_map<int, int> cnt; ll k = 0; for (int l = 0, r = 0; r < n; ++r) { int x = nums[r]; ++cnt[x]; while (cnt.size() > mx) { int y = nums[l++]; if (--cnt[y] == 0) { cnt.erase(y); } } k += r - l + 1; if (k >= (m + 1) / 2) { return true; } } return false; }; while (l < r) { int mid = (l + r) >> 1; if (check(mid)) { r = mid; } else { l = mid + 1; } } return l; } };
3,134
Find the Median of the Uniqueness Array
Hard
<p>You are given an integer array <code>nums</code>. The <strong>uniqueness array</strong> of <code>nums</code> is the sorted array that contains the number of distinct elements of all the <span data-keyword="subarray-nonempty">subarrays</span> of <code>nums</code>. In other words, it is a sorted array consisting of <code>distinct(nums[i..j])</code>, for all <code>0 &lt;= i &lt;= j &lt; nums.length</code>.</p> <p>Here, <code>distinct(nums[i..j])</code> denotes the number of distinct elements in the subarray that starts at index <code>i</code> and ends at index <code>j</code>.</p> <p>Return the <strong>median</strong> of the <strong>uniqueness array</strong> of <code>nums</code>.</p> <p><strong>Note</strong> that the <strong>median</strong> of an array is defined as the middle element of the array when it is sorted in non-decreasing order. If there are two choices for a median, the <strong>smaller</strong> of the two values is taken.<!-- notionvc: 7e0f5178-4273-4a82-95ce-3395297921dc --></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]</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <p>The uniqueness array of <code>nums</code> is <code>[distinct(nums[0..0]), distinct(nums[1..1]), distinct(nums[2..2]), distinct(nums[0..1]), distinct(nums[1..2]), distinct(nums[0..2])]</code> which is equal to <code>[1, 1, 1, 2, 2, 3]</code>. The uniqueness array has a median of 1. Therefore, the answer is 1.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [3,4,3,4,5]</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>The uniqueness array of <code>nums</code> is <code>[1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3]</code>. The uniqueness array has a median of 2. Therefore, the answer is 2.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [4,3,5,4]</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>The uniqueness array of <code>nums</code> is <code>[1, 1, 1, 1, 2, 2, 2, 3, 3, 3]</code>. The uniqueness array has a median of 2. Therefore, the answer is 2.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>5</sup></code></li> </ul>
Array; Hash Table; Binary Search; Sliding Window
Go
func medianOfUniquenessArray(nums []int) int { n := len(nums) m := (1 + n) * n / 2 return sort.Search(n, func(mx int) bool { cnt := map[int]int{} l, k := 0, 0 for r, x := range nums { cnt[x]++ for len(cnt) > mx { y := nums[l] cnt[y]-- if cnt[y] == 0 { delete(cnt, y) } l++ } k += r - l + 1 if k >= (m+1)/2 { return true } } return false }) }
3,134
Find the Median of the Uniqueness Array
Hard
<p>You are given an integer array <code>nums</code>. The <strong>uniqueness array</strong> of <code>nums</code> is the sorted array that contains the number of distinct elements of all the <span data-keyword="subarray-nonempty">subarrays</span> of <code>nums</code>. In other words, it is a sorted array consisting of <code>distinct(nums[i..j])</code>, for all <code>0 &lt;= i &lt;= j &lt; nums.length</code>.</p> <p>Here, <code>distinct(nums[i..j])</code> denotes the number of distinct elements in the subarray that starts at index <code>i</code> and ends at index <code>j</code>.</p> <p>Return the <strong>median</strong> of the <strong>uniqueness array</strong> of <code>nums</code>.</p> <p><strong>Note</strong> that the <strong>median</strong> of an array is defined as the middle element of the array when it is sorted in non-decreasing order. If there are two choices for a median, the <strong>smaller</strong> of the two values is taken.<!-- notionvc: 7e0f5178-4273-4a82-95ce-3395297921dc --></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]</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <p>The uniqueness array of <code>nums</code> is <code>[distinct(nums[0..0]), distinct(nums[1..1]), distinct(nums[2..2]), distinct(nums[0..1]), distinct(nums[1..2]), distinct(nums[0..2])]</code> which is equal to <code>[1, 1, 1, 2, 2, 3]</code>. The uniqueness array has a median of 1. Therefore, the answer is 1.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [3,4,3,4,5]</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>The uniqueness array of <code>nums</code> is <code>[1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3]</code>. The uniqueness array has a median of 2. Therefore, the answer is 2.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [4,3,5,4]</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>The uniqueness array of <code>nums</code> is <code>[1, 1, 1, 1, 2, 2, 2, 3, 3, 3]</code>. The uniqueness array has a median of 2. Therefore, the answer is 2.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>5</sup></code></li> </ul>
Array; Hash Table; Binary Search; Sliding Window
Java
class Solution { private long m; private int[] nums; public int medianOfUniquenessArray(int[] nums) { int n = nums.length; this.nums = nums; m = (1L + n) * n / 2; int l = 0, r = n; while (l < r) { int mid = (l + r) >> 1; if (check(mid)) { r = mid; } else { l = mid + 1; } } return l; } private boolean check(int mx) { Map<Integer, Integer> cnt = new HashMap<>(); long k = 0; for (int l = 0, r = 0; r < nums.length; ++r) { int x = nums[r]; cnt.merge(x, 1, Integer::sum); while (cnt.size() > mx) { int y = nums[l++]; if (cnt.merge(y, -1, Integer::sum) == 0) { cnt.remove(y); } } k += r - l + 1; if (k >= (m + 1) / 2) { return true; } } return false; } }
3,134
Find the Median of the Uniqueness Array
Hard
<p>You are given an integer array <code>nums</code>. The <strong>uniqueness array</strong> of <code>nums</code> is the sorted array that contains the number of distinct elements of all the <span data-keyword="subarray-nonempty">subarrays</span> of <code>nums</code>. In other words, it is a sorted array consisting of <code>distinct(nums[i..j])</code>, for all <code>0 &lt;= i &lt;= j &lt; nums.length</code>.</p> <p>Here, <code>distinct(nums[i..j])</code> denotes the number of distinct elements in the subarray that starts at index <code>i</code> and ends at index <code>j</code>.</p> <p>Return the <strong>median</strong> of the <strong>uniqueness array</strong> of <code>nums</code>.</p> <p><strong>Note</strong> that the <strong>median</strong> of an array is defined as the middle element of the array when it is sorted in non-decreasing order. If there are two choices for a median, the <strong>smaller</strong> of the two values is taken.<!-- notionvc: 7e0f5178-4273-4a82-95ce-3395297921dc --></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]</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <p>The uniqueness array of <code>nums</code> is <code>[distinct(nums[0..0]), distinct(nums[1..1]), distinct(nums[2..2]), distinct(nums[0..1]), distinct(nums[1..2]), distinct(nums[0..2])]</code> which is equal to <code>[1, 1, 1, 2, 2, 3]</code>. The uniqueness array has a median of 1. Therefore, the answer is 1.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [3,4,3,4,5]</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>The uniqueness array of <code>nums</code> is <code>[1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3]</code>. The uniqueness array has a median of 2. Therefore, the answer is 2.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [4,3,5,4]</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>The uniqueness array of <code>nums</code> is <code>[1, 1, 1, 1, 2, 2, 2, 3, 3, 3]</code>. The uniqueness array has a median of 2. Therefore, the answer is 2.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>5</sup></code></li> </ul>
Array; Hash Table; Binary Search; Sliding Window
Python
class Solution: def medianOfUniquenessArray(self, nums: List[int]) -> int: def check(mx: int) -> bool: cnt = defaultdict(int) k = l = 0 for r, x in enumerate(nums): cnt[x] += 1 while len(cnt) > mx: y = nums[l] cnt[y] -= 1 if cnt[y] == 0: cnt.pop(y) l += 1 k += r - l + 1 if k >= (m + 1) // 2: return True return False n = len(nums) m = (1 + n) * n // 2 return bisect_left(range(n), True, key=check)
3,134
Find the Median of the Uniqueness Array
Hard
<p>You are given an integer array <code>nums</code>. The <strong>uniqueness array</strong> of <code>nums</code> is the sorted array that contains the number of distinct elements of all the <span data-keyword="subarray-nonempty">subarrays</span> of <code>nums</code>. In other words, it is a sorted array consisting of <code>distinct(nums[i..j])</code>, for all <code>0 &lt;= i &lt;= j &lt; nums.length</code>.</p> <p>Here, <code>distinct(nums[i..j])</code> denotes the number of distinct elements in the subarray that starts at index <code>i</code> and ends at index <code>j</code>.</p> <p>Return the <strong>median</strong> of the <strong>uniqueness array</strong> of <code>nums</code>.</p> <p><strong>Note</strong> that the <strong>median</strong> of an array is defined as the middle element of the array when it is sorted in non-decreasing order. If there are two choices for a median, the <strong>smaller</strong> of the two values is taken.<!-- notionvc: 7e0f5178-4273-4a82-95ce-3395297921dc --></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]</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <p>The uniqueness array of <code>nums</code> is <code>[distinct(nums[0..0]), distinct(nums[1..1]), distinct(nums[2..2]), distinct(nums[0..1]), distinct(nums[1..2]), distinct(nums[0..2])]</code> which is equal to <code>[1, 1, 1, 2, 2, 3]</code>. The uniqueness array has a median of 1. Therefore, the answer is 1.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [3,4,3,4,5]</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>The uniqueness array of <code>nums</code> is <code>[1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3]</code>. The uniqueness array has a median of 2. Therefore, the answer is 2.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [4,3,5,4]</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>The uniqueness array of <code>nums</code> is <code>[1, 1, 1, 1, 2, 2, 2, 3, 3, 3]</code>. The uniqueness array has a median of 2. Therefore, the answer is 2.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>5</sup></code></li> </ul>
Array; Hash Table; Binary Search; Sliding Window
TypeScript
function medianOfUniquenessArray(nums: number[]): number { const n = nums.length; const m = Math.floor(((1 + n) * n) / 2); let [l, r] = [0, n]; const check = (mx: number): boolean => { const cnt = new Map<number, number>(); let [l, k] = [0, 0]; for (let r = 0; r < n; ++r) { const x = nums[r]; cnt.set(x, (cnt.get(x) || 0) + 1); while (cnt.size > mx) { const y = nums[l++]; cnt.set(y, cnt.get(y)! - 1); if (cnt.get(y) === 0) { cnt.delete(y); } } k += r - l + 1; if (k >= Math.floor((m + 1) / 2)) { return true; } } return false; }; while (l < r) { const mid = (l + r) >> 1; if (check(mid)) { r = mid; } else { l = mid + 1; } } return l; }
3,135
Equalize Strings by Adding or Removing Characters at Ends
Medium
<p>Given two strings <code>initial</code> and <code>target</code>, your task is to modify <code>initial</code> by performing a series of operations to make it equal to <code>target</code>.</p> <p>In one operation, you can add or remove <strong>one character</strong> only at the <em>beginning</em> or the <em>end</em> of the string <code>initial</code>.</p> <p>Return the <strong>minimum</strong> number of operations required to <em>transform</em> <code>initial</code> into <code>target</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">initial = &quot;abcde&quot;, target = &quot;cdef&quot;</span></p> <p><strong>Output:</strong> 3</p> <p><strong>Explanation:</strong></p> <p>Remove <code>&#39;a&#39;</code> and <code>&#39;b&#39;</code> from the beginning of <code>initial</code>, then add <code>&#39;f&#39;</code> to the end.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">initial = &quot;axxy&quot;, target = &quot;yabx&quot;</span></p> <p><strong>Output:</strong> 6</p> <p><strong>Explanation:</strong></p> <table border="1"> <tbody> <tr> <th>Operation</th> <th>Resulting String</th> </tr> <tr> <td>Add <code>&#39;y&#39;</code> to the beginning</td> <td><code>&quot;yaxxy&quot;</code></td> </tr> <tr> <td>Remove from end</td> <td><code>&quot;yaxx&quot;</code></td> </tr> <tr> <td>Remove from end</td> <td><code>&quot;yax&quot;</code></td> </tr> <tr> <td>Remove from end</td> <td><code>&quot;ya&quot;</code></td> </tr> <tr> <td>Add <code>&#39;b&#39;</code> to the end</td> <td><code>&quot;yab&quot;</code></td> </tr> <tr> <td>Add <code>&#39;x&#39;</code> to the end</td> <td><code>&quot;yabx&quot;</code></td> </tr> </tbody> </table> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">initial = &quot;xyz&quot;, target = &quot;xyz&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>No operations are needed as the strings are already equal.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= initial.length, target.length &lt;= 1000</code></li> <li><code>initial</code> and <code>target</code> consist only of lowercase English letters.</li> </ul>
String; Binary Search; Dynamic Programming; Sliding Window; Hash Function
C++
class Solution { public: int minOperations(string initial, string target) { int m = initial.size(), n = target.size(); int f[m + 1][n + 1]; memset(f, 0, sizeof(f)); int mx = 0; for (int i = 1; i <= m; ++i) { for (int j = 1; j <= n; ++j) { if (initial[i - 1] == target[j - 1]) { f[i][j] = f[i - 1][j - 1] + 1; mx = max(mx, f[i][j]); } } } return m + n - 2 * mx; } };
3,135
Equalize Strings by Adding or Removing Characters at Ends
Medium
<p>Given two strings <code>initial</code> and <code>target</code>, your task is to modify <code>initial</code> by performing a series of operations to make it equal to <code>target</code>.</p> <p>In one operation, you can add or remove <strong>one character</strong> only at the <em>beginning</em> or the <em>end</em> of the string <code>initial</code>.</p> <p>Return the <strong>minimum</strong> number of operations required to <em>transform</em> <code>initial</code> into <code>target</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">initial = &quot;abcde&quot;, target = &quot;cdef&quot;</span></p> <p><strong>Output:</strong> 3</p> <p><strong>Explanation:</strong></p> <p>Remove <code>&#39;a&#39;</code> and <code>&#39;b&#39;</code> from the beginning of <code>initial</code>, then add <code>&#39;f&#39;</code> to the end.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">initial = &quot;axxy&quot;, target = &quot;yabx&quot;</span></p> <p><strong>Output:</strong> 6</p> <p><strong>Explanation:</strong></p> <table border="1"> <tbody> <tr> <th>Operation</th> <th>Resulting String</th> </tr> <tr> <td>Add <code>&#39;y&#39;</code> to the beginning</td> <td><code>&quot;yaxxy&quot;</code></td> </tr> <tr> <td>Remove from end</td> <td><code>&quot;yaxx&quot;</code></td> </tr> <tr> <td>Remove from end</td> <td><code>&quot;yax&quot;</code></td> </tr> <tr> <td>Remove from end</td> <td><code>&quot;ya&quot;</code></td> </tr> <tr> <td>Add <code>&#39;b&#39;</code> to the end</td> <td><code>&quot;yab&quot;</code></td> </tr> <tr> <td>Add <code>&#39;x&#39;</code> to the end</td> <td><code>&quot;yabx&quot;</code></td> </tr> </tbody> </table> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">initial = &quot;xyz&quot;, target = &quot;xyz&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>No operations are needed as the strings are already equal.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= initial.length, target.length &lt;= 1000</code></li> <li><code>initial</code> and <code>target</code> consist only of lowercase English letters.</li> </ul>
String; Binary Search; Dynamic Programming; Sliding Window; Hash Function
Go
func minOperations(initial string, target string) int { m, n := len(initial), len(target) f := make([][]int, m+1) for i := range f { f[i] = make([]int, n+1) } mx := 0 for i, a := range initial { for j, b := range target { if a == b { f[i+1][j+1] = f[i][j] + 1 mx = max(mx, f[i+1][j+1]) } } } return m + n - 2*mx }
3,135
Equalize Strings by Adding or Removing Characters at Ends
Medium
<p>Given two strings <code>initial</code> and <code>target</code>, your task is to modify <code>initial</code> by performing a series of operations to make it equal to <code>target</code>.</p> <p>In one operation, you can add or remove <strong>one character</strong> only at the <em>beginning</em> or the <em>end</em> of the string <code>initial</code>.</p> <p>Return the <strong>minimum</strong> number of operations required to <em>transform</em> <code>initial</code> into <code>target</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">initial = &quot;abcde&quot;, target = &quot;cdef&quot;</span></p> <p><strong>Output:</strong> 3</p> <p><strong>Explanation:</strong></p> <p>Remove <code>&#39;a&#39;</code> and <code>&#39;b&#39;</code> from the beginning of <code>initial</code>, then add <code>&#39;f&#39;</code> to the end.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">initial = &quot;axxy&quot;, target = &quot;yabx&quot;</span></p> <p><strong>Output:</strong> 6</p> <p><strong>Explanation:</strong></p> <table border="1"> <tbody> <tr> <th>Operation</th> <th>Resulting String</th> </tr> <tr> <td>Add <code>&#39;y&#39;</code> to the beginning</td> <td><code>&quot;yaxxy&quot;</code></td> </tr> <tr> <td>Remove from end</td> <td><code>&quot;yaxx&quot;</code></td> </tr> <tr> <td>Remove from end</td> <td><code>&quot;yax&quot;</code></td> </tr> <tr> <td>Remove from end</td> <td><code>&quot;ya&quot;</code></td> </tr> <tr> <td>Add <code>&#39;b&#39;</code> to the end</td> <td><code>&quot;yab&quot;</code></td> </tr> <tr> <td>Add <code>&#39;x&#39;</code> to the end</td> <td><code>&quot;yabx&quot;</code></td> </tr> </tbody> </table> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">initial = &quot;xyz&quot;, target = &quot;xyz&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>No operations are needed as the strings are already equal.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= initial.length, target.length &lt;= 1000</code></li> <li><code>initial</code> and <code>target</code> consist only of lowercase English letters.</li> </ul>
String; Binary Search; Dynamic Programming; Sliding Window; Hash Function
Java
class Solution { public int minOperations(String initial, String target) { int m = initial.length(), n = target.length(); int[][] f = new int[m + 1][n + 1]; int mx = 0; for (int i = 1; i <= m; ++i) { for (int j = 1; j <= n; ++j) { if (initial.charAt(i - 1) == target.charAt(j - 1)) { f[i][j] = f[i - 1][j - 1] + 1; mx = Math.max(mx, f[i][j]); } } } return m + n - 2 * mx; } }
3,135
Equalize Strings by Adding or Removing Characters at Ends
Medium
<p>Given two strings <code>initial</code> and <code>target</code>, your task is to modify <code>initial</code> by performing a series of operations to make it equal to <code>target</code>.</p> <p>In one operation, you can add or remove <strong>one character</strong> only at the <em>beginning</em> or the <em>end</em> of the string <code>initial</code>.</p> <p>Return the <strong>minimum</strong> number of operations required to <em>transform</em> <code>initial</code> into <code>target</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">initial = &quot;abcde&quot;, target = &quot;cdef&quot;</span></p> <p><strong>Output:</strong> 3</p> <p><strong>Explanation:</strong></p> <p>Remove <code>&#39;a&#39;</code> and <code>&#39;b&#39;</code> from the beginning of <code>initial</code>, then add <code>&#39;f&#39;</code> to the end.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">initial = &quot;axxy&quot;, target = &quot;yabx&quot;</span></p> <p><strong>Output:</strong> 6</p> <p><strong>Explanation:</strong></p> <table border="1"> <tbody> <tr> <th>Operation</th> <th>Resulting String</th> </tr> <tr> <td>Add <code>&#39;y&#39;</code> to the beginning</td> <td><code>&quot;yaxxy&quot;</code></td> </tr> <tr> <td>Remove from end</td> <td><code>&quot;yaxx&quot;</code></td> </tr> <tr> <td>Remove from end</td> <td><code>&quot;yax&quot;</code></td> </tr> <tr> <td>Remove from end</td> <td><code>&quot;ya&quot;</code></td> </tr> <tr> <td>Add <code>&#39;b&#39;</code> to the end</td> <td><code>&quot;yab&quot;</code></td> </tr> <tr> <td>Add <code>&#39;x&#39;</code> to the end</td> <td><code>&quot;yabx&quot;</code></td> </tr> </tbody> </table> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">initial = &quot;xyz&quot;, target = &quot;xyz&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>No operations are needed as the strings are already equal.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= initial.length, target.length &lt;= 1000</code></li> <li><code>initial</code> and <code>target</code> consist only of lowercase English letters.</li> </ul>
String; Binary Search; Dynamic Programming; Sliding Window; Hash Function
Python
class Solution: def minOperations(self, initial: str, target: str) -> int: m, n = len(initial), len(target) f = [[0] * (n + 1) for _ in range(m + 1)] mx = 0 for i, a in enumerate(initial, 1): for j, b in enumerate(target, 1): if a == b: f[i][j] = f[i - 1][j - 1] + 1 mx = max(mx, f[i][j]) return m + n - mx * 2
3,135
Equalize Strings by Adding or Removing Characters at Ends
Medium
<p>Given two strings <code>initial</code> and <code>target</code>, your task is to modify <code>initial</code> by performing a series of operations to make it equal to <code>target</code>.</p> <p>In one operation, you can add or remove <strong>one character</strong> only at the <em>beginning</em> or the <em>end</em> of the string <code>initial</code>.</p> <p>Return the <strong>minimum</strong> number of operations required to <em>transform</em> <code>initial</code> into <code>target</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">initial = &quot;abcde&quot;, target = &quot;cdef&quot;</span></p> <p><strong>Output:</strong> 3</p> <p><strong>Explanation:</strong></p> <p>Remove <code>&#39;a&#39;</code> and <code>&#39;b&#39;</code> from the beginning of <code>initial</code>, then add <code>&#39;f&#39;</code> to the end.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">initial = &quot;axxy&quot;, target = &quot;yabx&quot;</span></p> <p><strong>Output:</strong> 6</p> <p><strong>Explanation:</strong></p> <table border="1"> <tbody> <tr> <th>Operation</th> <th>Resulting String</th> </tr> <tr> <td>Add <code>&#39;y&#39;</code> to the beginning</td> <td><code>&quot;yaxxy&quot;</code></td> </tr> <tr> <td>Remove from end</td> <td><code>&quot;yaxx&quot;</code></td> </tr> <tr> <td>Remove from end</td> <td><code>&quot;yax&quot;</code></td> </tr> <tr> <td>Remove from end</td> <td><code>&quot;ya&quot;</code></td> </tr> <tr> <td>Add <code>&#39;b&#39;</code> to the end</td> <td><code>&quot;yab&quot;</code></td> </tr> <tr> <td>Add <code>&#39;x&#39;</code> to the end</td> <td><code>&quot;yabx&quot;</code></td> </tr> </tbody> </table> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">initial = &quot;xyz&quot;, target = &quot;xyz&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>No operations are needed as the strings are already equal.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= initial.length, target.length &lt;= 1000</code></li> <li><code>initial</code> and <code>target</code> consist only of lowercase English letters.</li> </ul>
String; Binary Search; Dynamic Programming; Sliding Window; Hash Function
TypeScript
function minOperations(initial: string, target: string): number { const m = initial.length; const n = target.length; const f: number[][] = Array.from({ length: m + 1 }, () => Array(n + 1).fill(0)); let mx: number = 0; for (let i = 1; i <= m; ++i) { for (let j = 1; j <= n; ++j) { if (initial[i - 1] === target[j - 1]) { f[i][j] = f[i - 1][j - 1] + 1; mx = Math.max(mx, f[i][j]); } } } return m + n - 2 * mx; }
3,136
Valid Word
Easy
<p>A word is considered <strong>valid</strong> if:</p> <ul> <li>It contains a <strong>minimum</strong> of 3 characters.</li> <li>It contains only digits (0-9), and English letters (uppercase and lowercase).</li> <li>It includes <strong>at least</strong> one <strong>vowel</strong>.</li> <li>It includes <strong>at least</strong> one <strong>consonant</strong>.</li> </ul> <p>You are given a string <code>word</code>.</p> <p>Return <code>true</code> if <code>word</code> is valid, otherwise, return <code>false</code>.</p> <p><strong>Notes:</strong></p> <ul> <li><code>&#39;a&#39;</code>, <code>&#39;e&#39;</code>, <code>&#39;i&#39;</code>, <code>&#39;o&#39;</code>, <code>&#39;u&#39;</code>, and their uppercases are <strong>vowels</strong>.</li> <li>A <strong>consonant</strong> is an English letter that is not a vowel.</li> </ul> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">word = &quot;234Adas&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">true</span></p> <p><strong>Explanation:</strong></p> <p>This word satisfies the conditions.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">word = &quot;b3&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p>The length of this word is fewer than 3, and does not have a vowel.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">word = &quot;a3$e&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p>This word contains a <code>&#39;$&#39;</code> character and does not have a consonant.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= word.length &lt;= 20</code></li> <li><code>word</code> consists of English uppercase and lowercase letters, digits, <code>&#39;@&#39;</code>, <code>&#39;#&#39;</code>, and <code>&#39;$&#39;</code>.</li> </ul>
String
C++
class Solution { public: bool isValid(string word) { if (word.size() < 3) { return false; } bool has_vowel = false, has_consonant = false; bool vs[26]{}; string vowels = "aeiou"; for (char c : vowels) { vs[c - 'a'] = true; } for (char c : word) { if (isalpha(c)) { if (vs[tolower(c) - 'a']) { has_vowel = true; } else { has_consonant = true; } } else if (!isdigit(c)) { return false; } } return has_vowel && has_consonant; } };
3,136
Valid Word
Easy
<p>A word is considered <strong>valid</strong> if:</p> <ul> <li>It contains a <strong>minimum</strong> of 3 characters.</li> <li>It contains only digits (0-9), and English letters (uppercase and lowercase).</li> <li>It includes <strong>at least</strong> one <strong>vowel</strong>.</li> <li>It includes <strong>at least</strong> one <strong>consonant</strong>.</li> </ul> <p>You are given a string <code>word</code>.</p> <p>Return <code>true</code> if <code>word</code> is valid, otherwise, return <code>false</code>.</p> <p><strong>Notes:</strong></p> <ul> <li><code>&#39;a&#39;</code>, <code>&#39;e&#39;</code>, <code>&#39;i&#39;</code>, <code>&#39;o&#39;</code>, <code>&#39;u&#39;</code>, and their uppercases are <strong>vowels</strong>.</li> <li>A <strong>consonant</strong> is an English letter that is not a vowel.</li> </ul> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">word = &quot;234Adas&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">true</span></p> <p><strong>Explanation:</strong></p> <p>This word satisfies the conditions.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">word = &quot;b3&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p>The length of this word is fewer than 3, and does not have a vowel.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">word = &quot;a3$e&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p>This word contains a <code>&#39;$&#39;</code> character and does not have a consonant.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= word.length &lt;= 20</code></li> <li><code>word</code> consists of English uppercase and lowercase letters, digits, <code>&#39;@&#39;</code>, <code>&#39;#&#39;</code>, and <code>&#39;$&#39;</code>.</li> </ul>
String
C#
public class Solution { public bool IsValid(string word) { if (word.Length < 3) { return false; } bool hasVowel = false, hasConsonant = false; bool[] vs = new bool[26]; foreach (char c in "aeiou") { vs[c - 'a'] = true; } foreach (char c in word) { if (char.IsLetter(c)) { char lower = char.ToLower(c); if (vs[lower - 'a']) { hasVowel = true; } else { hasConsonant = true; } } else if (!char.IsDigit(c)) { return false; } } return hasVowel && hasConsonant; } }
3,136
Valid Word
Easy
<p>A word is considered <strong>valid</strong> if:</p> <ul> <li>It contains a <strong>minimum</strong> of 3 characters.</li> <li>It contains only digits (0-9), and English letters (uppercase and lowercase).</li> <li>It includes <strong>at least</strong> one <strong>vowel</strong>.</li> <li>It includes <strong>at least</strong> one <strong>consonant</strong>.</li> </ul> <p>You are given a string <code>word</code>.</p> <p>Return <code>true</code> if <code>word</code> is valid, otherwise, return <code>false</code>.</p> <p><strong>Notes:</strong></p> <ul> <li><code>&#39;a&#39;</code>, <code>&#39;e&#39;</code>, <code>&#39;i&#39;</code>, <code>&#39;o&#39;</code>, <code>&#39;u&#39;</code>, and their uppercases are <strong>vowels</strong>.</li> <li>A <strong>consonant</strong> is an English letter that is not a vowel.</li> </ul> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">word = &quot;234Adas&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">true</span></p> <p><strong>Explanation:</strong></p> <p>This word satisfies the conditions.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">word = &quot;b3&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p>The length of this word is fewer than 3, and does not have a vowel.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">word = &quot;a3$e&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p>This word contains a <code>&#39;$&#39;</code> character and does not have a consonant.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= word.length &lt;= 20</code></li> <li><code>word</code> consists of English uppercase and lowercase letters, digits, <code>&#39;@&#39;</code>, <code>&#39;#&#39;</code>, and <code>&#39;$&#39;</code>.</li> </ul>
String
Go
func isValid(word string) bool { if len(word) < 3 { return false } hasVowel := false hasConsonant := false vs := make([]bool, 26) for _, c := range "aeiou" { vs[c-'a'] = true } for _, c := range word { if unicode.IsLetter(c) { if vs[unicode.ToLower(c)-'a'] { hasVowel = true } else { hasConsonant = true } } else if !unicode.IsDigit(c) { return false } } return hasVowel && hasConsonant }
3,136
Valid Word
Easy
<p>A word is considered <strong>valid</strong> if:</p> <ul> <li>It contains a <strong>minimum</strong> of 3 characters.</li> <li>It contains only digits (0-9), and English letters (uppercase and lowercase).</li> <li>It includes <strong>at least</strong> one <strong>vowel</strong>.</li> <li>It includes <strong>at least</strong> one <strong>consonant</strong>.</li> </ul> <p>You are given a string <code>word</code>.</p> <p>Return <code>true</code> if <code>word</code> is valid, otherwise, return <code>false</code>.</p> <p><strong>Notes:</strong></p> <ul> <li><code>&#39;a&#39;</code>, <code>&#39;e&#39;</code>, <code>&#39;i&#39;</code>, <code>&#39;o&#39;</code>, <code>&#39;u&#39;</code>, and their uppercases are <strong>vowels</strong>.</li> <li>A <strong>consonant</strong> is an English letter that is not a vowel.</li> </ul> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">word = &quot;234Adas&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">true</span></p> <p><strong>Explanation:</strong></p> <p>This word satisfies the conditions.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">word = &quot;b3&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p>The length of this word is fewer than 3, and does not have a vowel.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">word = &quot;a3$e&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p>This word contains a <code>&#39;$&#39;</code> character and does not have a consonant.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= word.length &lt;= 20</code></li> <li><code>word</code> consists of English uppercase and lowercase letters, digits, <code>&#39;@&#39;</code>, <code>&#39;#&#39;</code>, and <code>&#39;$&#39;</code>.</li> </ul>
String
Java
class Solution { public boolean isValid(String word) { if (word.length() < 3) { return false; } boolean hasVowel = false, hasConsonant = false; boolean[] vs = new boolean[26]; for (char c : "aeiou".toCharArray()) { vs[c - 'a'] = true; } for (char c : word.toCharArray()) { if (Character.isAlphabetic(c)) { if (vs[Character.toLowerCase(c) - 'a']) { hasVowel = true; } else { hasConsonant = true; } } else if (!Character.isDigit(c)) { return false; } } return hasVowel && hasConsonant; } }
3,136
Valid Word
Easy
<p>A word is considered <strong>valid</strong> if:</p> <ul> <li>It contains a <strong>minimum</strong> of 3 characters.</li> <li>It contains only digits (0-9), and English letters (uppercase and lowercase).</li> <li>It includes <strong>at least</strong> one <strong>vowel</strong>.</li> <li>It includes <strong>at least</strong> one <strong>consonant</strong>.</li> </ul> <p>You are given a string <code>word</code>.</p> <p>Return <code>true</code> if <code>word</code> is valid, otherwise, return <code>false</code>.</p> <p><strong>Notes:</strong></p> <ul> <li><code>&#39;a&#39;</code>, <code>&#39;e&#39;</code>, <code>&#39;i&#39;</code>, <code>&#39;o&#39;</code>, <code>&#39;u&#39;</code>, and their uppercases are <strong>vowels</strong>.</li> <li>A <strong>consonant</strong> is an English letter that is not a vowel.</li> </ul> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">word = &quot;234Adas&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">true</span></p> <p><strong>Explanation:</strong></p> <p>This word satisfies the conditions.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">word = &quot;b3&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p>The length of this word is fewer than 3, and does not have a vowel.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">word = &quot;a3$e&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p>This word contains a <code>&#39;$&#39;</code> character and does not have a consonant.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= word.length &lt;= 20</code></li> <li><code>word</code> consists of English uppercase and lowercase letters, digits, <code>&#39;@&#39;</code>, <code>&#39;#&#39;</code>, and <code>&#39;$&#39;</code>.</li> </ul>
String
Python
class Solution: def isValid(self, word: str) -> bool: if len(word) < 3: return False has_vowel = has_consonant = False vs = set("aeiouAEIOU") for c in word: if not c.isalnum(): return False if c.isalpha(): if c in vs: has_vowel = True else: has_consonant = True return has_vowel and has_consonant
3,136
Valid Word
Easy
<p>A word is considered <strong>valid</strong> if:</p> <ul> <li>It contains a <strong>minimum</strong> of 3 characters.</li> <li>It contains only digits (0-9), and English letters (uppercase and lowercase).</li> <li>It includes <strong>at least</strong> one <strong>vowel</strong>.</li> <li>It includes <strong>at least</strong> one <strong>consonant</strong>.</li> </ul> <p>You are given a string <code>word</code>.</p> <p>Return <code>true</code> if <code>word</code> is valid, otherwise, return <code>false</code>.</p> <p><strong>Notes:</strong></p> <ul> <li><code>&#39;a&#39;</code>, <code>&#39;e&#39;</code>, <code>&#39;i&#39;</code>, <code>&#39;o&#39;</code>, <code>&#39;u&#39;</code>, and their uppercases are <strong>vowels</strong>.</li> <li>A <strong>consonant</strong> is an English letter that is not a vowel.</li> </ul> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">word = &quot;234Adas&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">true</span></p> <p><strong>Explanation:</strong></p> <p>This word satisfies the conditions.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">word = &quot;b3&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p>The length of this word is fewer than 3, and does not have a vowel.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">word = &quot;a3$e&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p>This word contains a <code>&#39;$&#39;</code> character and does not have a consonant.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= word.length &lt;= 20</code></li> <li><code>word</code> consists of English uppercase and lowercase letters, digits, <code>&#39;@&#39;</code>, <code>&#39;#&#39;</code>, and <code>&#39;$&#39;</code>.</li> </ul>
String
Rust
impl Solution { pub fn is_valid(word: String) -> bool { if word.len() < 3 { return false; } let mut has_vowel = false; let mut has_consonant = false; let vowels = ['a', 'e', 'i', 'o', 'u']; for c in word.chars() { if !c.is_alphanumeric() { return false; } if c.is_alphabetic() { let lower_c = c.to_ascii_lowercase(); if vowels.contains(&lower_c) { has_vowel = true; } else { has_consonant = true; } } } has_vowel && has_consonant } }
3,136
Valid Word
Easy
<p>A word is considered <strong>valid</strong> if:</p> <ul> <li>It contains a <strong>minimum</strong> of 3 characters.</li> <li>It contains only digits (0-9), and English letters (uppercase and lowercase).</li> <li>It includes <strong>at least</strong> one <strong>vowel</strong>.</li> <li>It includes <strong>at least</strong> one <strong>consonant</strong>.</li> </ul> <p>You are given a string <code>word</code>.</p> <p>Return <code>true</code> if <code>word</code> is valid, otherwise, return <code>false</code>.</p> <p><strong>Notes:</strong></p> <ul> <li><code>&#39;a&#39;</code>, <code>&#39;e&#39;</code>, <code>&#39;i&#39;</code>, <code>&#39;o&#39;</code>, <code>&#39;u&#39;</code>, and their uppercases are <strong>vowels</strong>.</li> <li>A <strong>consonant</strong> is an English letter that is not a vowel.</li> </ul> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">word = &quot;234Adas&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">true</span></p> <p><strong>Explanation:</strong></p> <p>This word satisfies the conditions.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">word = &quot;b3&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p>The length of this word is fewer than 3, and does not have a vowel.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">word = &quot;a3$e&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p>This word contains a <code>&#39;$&#39;</code> character and does not have a consonant.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= word.length &lt;= 20</code></li> <li><code>word</code> consists of English uppercase and lowercase letters, digits, <code>&#39;@&#39;</code>, <code>&#39;#&#39;</code>, and <code>&#39;$&#39;</code>.</li> </ul>
String
TypeScript
function isValid(word: string): boolean { if (word.length < 3) { return false; } let hasVowel: boolean = false; let hasConsonant: boolean = false; const vowels: Set<string> = new Set(['a', 'e', 'i', 'o', 'u', 'A', 'E', 'I', 'O', 'U']); for (const c of word) { if (!c.match(/[a-zA-Z0-9]/)) { return false; } if (/[a-zA-Z]/.test(c)) { if (vowels.has(c)) { hasVowel = true; } else { hasConsonant = true; } } } return hasVowel && hasConsonant; }
3,137
Minimum Number of Operations to Make Word K-Periodic
Medium
<p>You are given a string <code>word</code> of size <code>n</code>, and an integer <code>k</code> such that <code>k</code> divides <code>n</code>.</p> <p>In one operation, you can pick any two indices <code>i</code> and <code>j</code>, that are divisible by <code>k</code>, then replace the <span data-keyword="substring">substring</span> of length <code>k</code> starting at <code>i</code> with the substring of length <code>k</code> starting at <code>j</code>. That is, replace the substring <code>word[i..i + k - 1]</code> with the substring <code>word[j..j + k - 1]</code>.<!-- notionvc: 49ac84f7-0724-452a-ab43-0c5e53f1db33 --></p> <p>Return <em>the <strong>minimum</strong> number of operations required to make</em> <code>word</code> <em><strong>k-periodic</strong></em>.</p> <p>We say that <code>word</code> is <strong>k-periodic</strong> if there is some string <code>s</code> of length <code>k</code> such that <code>word</code> can be obtained by concatenating <code>s</code> an arbitrary number of times. For example, if <code>word == &ldquo;ababab&rdquo;</code>, then <code>word</code> is 2-periodic for <code>s = &quot;ab&quot;</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" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; ">word = &quot;leetcodeleet&quot;, k = 4</span></p> <p><strong>Output:</strong> <span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; ">1</span></p> <p><strong>Explanation:</strong></p> <p>We can obtain a 4-periodic string by picking i = 4 and j = 0. After this operation, word becomes equal to &quot;leetleetleet&quot;.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; ">word = &quot;</span>leetcoleet<span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; ">&quot;, k = 2</span></p> <p><strong>Output:</strong> 3</p> <p><strong>Explanation:</strong></p> <p>We can obtain a 2-periodic string by applying the operations in the table below.</p> <table border="1" bordercolor="#ccc" cellpadding="5" cellspacing="0" height="146" style="border-collapse:collapse; text-align: center; vertical-align: middle;"> <tbody> <tr> <th>i</th> <th>j</th> <th>word</th> </tr> <tr> <td style="padding: 5px 15px;">0</td> <td style="padding: 5px 15px;">2</td> <td style="padding: 5px 15px;">etetcoleet</td> </tr> <tr> <td style="padding: 5px 15px;">4</td> <td style="padding: 5px 15px;">0</td> <td style="padding: 5px 15px;">etetetleet</td> </tr> <tr> <td style="padding: 5px 15px;">6</td> <td style="padding: 5px 15px;">0</td> <td style="padding: 5px 15px;">etetetetet</td> </tr> </tbody> </table> </div> <div id="gtx-trans" style="position: absolute; left: 107px; top: 238.5px;"> <div class="gtx-trans-icon">&nbsp;</div> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == word.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= k &lt;= word.length</code></li> <li><code>k</code> divides <code>word.length</code>.</li> <li><code>word</code> consists only of lowercase English letters.</li> </ul>
Hash Table; String; Counting
C++
class Solution { public: int minimumOperationsToMakeKPeriodic(string word, int k) { unordered_map<string, int> cnt; int n = word.size(); int mx = 0; for (int i = 0; i < n; i += k) { mx = max(mx, ++cnt[word.substr(i, k)]); } return n / k - mx; } };
3,137
Minimum Number of Operations to Make Word K-Periodic
Medium
<p>You are given a string <code>word</code> of size <code>n</code>, and an integer <code>k</code> such that <code>k</code> divides <code>n</code>.</p> <p>In one operation, you can pick any two indices <code>i</code> and <code>j</code>, that are divisible by <code>k</code>, then replace the <span data-keyword="substring">substring</span> of length <code>k</code> starting at <code>i</code> with the substring of length <code>k</code> starting at <code>j</code>. That is, replace the substring <code>word[i..i + k - 1]</code> with the substring <code>word[j..j + k - 1]</code>.<!-- notionvc: 49ac84f7-0724-452a-ab43-0c5e53f1db33 --></p> <p>Return <em>the <strong>minimum</strong> number of operations required to make</em> <code>word</code> <em><strong>k-periodic</strong></em>.</p> <p>We say that <code>word</code> is <strong>k-periodic</strong> if there is some string <code>s</code> of length <code>k</code> such that <code>word</code> can be obtained by concatenating <code>s</code> an arbitrary number of times. For example, if <code>word == &ldquo;ababab&rdquo;</code>, then <code>word</code> is 2-periodic for <code>s = &quot;ab&quot;</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" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; ">word = &quot;leetcodeleet&quot;, k = 4</span></p> <p><strong>Output:</strong> <span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; ">1</span></p> <p><strong>Explanation:</strong></p> <p>We can obtain a 4-periodic string by picking i = 4 and j = 0. After this operation, word becomes equal to &quot;leetleetleet&quot;.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; ">word = &quot;</span>leetcoleet<span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; ">&quot;, k = 2</span></p> <p><strong>Output:</strong> 3</p> <p><strong>Explanation:</strong></p> <p>We can obtain a 2-periodic string by applying the operations in the table below.</p> <table border="1" bordercolor="#ccc" cellpadding="5" cellspacing="0" height="146" style="border-collapse:collapse; text-align: center; vertical-align: middle;"> <tbody> <tr> <th>i</th> <th>j</th> <th>word</th> </tr> <tr> <td style="padding: 5px 15px;">0</td> <td style="padding: 5px 15px;">2</td> <td style="padding: 5px 15px;">etetcoleet</td> </tr> <tr> <td style="padding: 5px 15px;">4</td> <td style="padding: 5px 15px;">0</td> <td style="padding: 5px 15px;">etetetleet</td> </tr> <tr> <td style="padding: 5px 15px;">6</td> <td style="padding: 5px 15px;">0</td> <td style="padding: 5px 15px;">etetetetet</td> </tr> </tbody> </table> </div> <div id="gtx-trans" style="position: absolute; left: 107px; top: 238.5px;"> <div class="gtx-trans-icon">&nbsp;</div> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == word.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= k &lt;= word.length</code></li> <li><code>k</code> divides <code>word.length</code>.</li> <li><code>word</code> consists only of lowercase English letters.</li> </ul>
Hash Table; String; Counting
Go
func minimumOperationsToMakeKPeriodic(word string, k int) int { cnt := map[string]int{} n := len(word) mx := 0 for i := 0; i < n; i += k { s := word[i : i+k] cnt[s]++ mx = max(mx, cnt[s]) } return n/k - mx }
3,137
Minimum Number of Operations to Make Word K-Periodic
Medium
<p>You are given a string <code>word</code> of size <code>n</code>, and an integer <code>k</code> such that <code>k</code> divides <code>n</code>.</p> <p>In one operation, you can pick any two indices <code>i</code> and <code>j</code>, that are divisible by <code>k</code>, then replace the <span data-keyword="substring">substring</span> of length <code>k</code> starting at <code>i</code> with the substring of length <code>k</code> starting at <code>j</code>. That is, replace the substring <code>word[i..i + k - 1]</code> with the substring <code>word[j..j + k - 1]</code>.<!-- notionvc: 49ac84f7-0724-452a-ab43-0c5e53f1db33 --></p> <p>Return <em>the <strong>minimum</strong> number of operations required to make</em> <code>word</code> <em><strong>k-periodic</strong></em>.</p> <p>We say that <code>word</code> is <strong>k-periodic</strong> if there is some string <code>s</code> of length <code>k</code> such that <code>word</code> can be obtained by concatenating <code>s</code> an arbitrary number of times. For example, if <code>word == &ldquo;ababab&rdquo;</code>, then <code>word</code> is 2-periodic for <code>s = &quot;ab&quot;</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" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; ">word = &quot;leetcodeleet&quot;, k = 4</span></p> <p><strong>Output:</strong> <span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; ">1</span></p> <p><strong>Explanation:</strong></p> <p>We can obtain a 4-periodic string by picking i = 4 and j = 0. After this operation, word becomes equal to &quot;leetleetleet&quot;.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; ">word = &quot;</span>leetcoleet<span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; ">&quot;, k = 2</span></p> <p><strong>Output:</strong> 3</p> <p><strong>Explanation:</strong></p> <p>We can obtain a 2-periodic string by applying the operations in the table below.</p> <table border="1" bordercolor="#ccc" cellpadding="5" cellspacing="0" height="146" style="border-collapse:collapse; text-align: center; vertical-align: middle;"> <tbody> <tr> <th>i</th> <th>j</th> <th>word</th> </tr> <tr> <td style="padding: 5px 15px;">0</td> <td style="padding: 5px 15px;">2</td> <td style="padding: 5px 15px;">etetcoleet</td> </tr> <tr> <td style="padding: 5px 15px;">4</td> <td style="padding: 5px 15px;">0</td> <td style="padding: 5px 15px;">etetetleet</td> </tr> <tr> <td style="padding: 5px 15px;">6</td> <td style="padding: 5px 15px;">0</td> <td style="padding: 5px 15px;">etetetetet</td> </tr> </tbody> </table> </div> <div id="gtx-trans" style="position: absolute; left: 107px; top: 238.5px;"> <div class="gtx-trans-icon">&nbsp;</div> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == word.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= k &lt;= word.length</code></li> <li><code>k</code> divides <code>word.length</code>.</li> <li><code>word</code> consists only of lowercase English letters.</li> </ul>
Hash Table; String; Counting
Java
class Solution { public int minimumOperationsToMakeKPeriodic(String word, int k) { Map<String, Integer> cnt = new HashMap<>(); int n = word.length(); int mx = 0; for (int i = 0; i < n; i += k) { mx = Math.max(mx, cnt.merge(word.substring(i, i + k), 1, Integer::sum)); } return n / k - mx; } }
3,137
Minimum Number of Operations to Make Word K-Periodic
Medium
<p>You are given a string <code>word</code> of size <code>n</code>, and an integer <code>k</code> such that <code>k</code> divides <code>n</code>.</p> <p>In one operation, you can pick any two indices <code>i</code> and <code>j</code>, that are divisible by <code>k</code>, then replace the <span data-keyword="substring">substring</span> of length <code>k</code> starting at <code>i</code> with the substring of length <code>k</code> starting at <code>j</code>. That is, replace the substring <code>word[i..i + k - 1]</code> with the substring <code>word[j..j + k - 1]</code>.<!-- notionvc: 49ac84f7-0724-452a-ab43-0c5e53f1db33 --></p> <p>Return <em>the <strong>minimum</strong> number of operations required to make</em> <code>word</code> <em><strong>k-periodic</strong></em>.</p> <p>We say that <code>word</code> is <strong>k-periodic</strong> if there is some string <code>s</code> of length <code>k</code> such that <code>word</code> can be obtained by concatenating <code>s</code> an arbitrary number of times. For example, if <code>word == &ldquo;ababab&rdquo;</code>, then <code>word</code> is 2-periodic for <code>s = &quot;ab&quot;</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" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; ">word = &quot;leetcodeleet&quot;, k = 4</span></p> <p><strong>Output:</strong> <span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; ">1</span></p> <p><strong>Explanation:</strong></p> <p>We can obtain a 4-periodic string by picking i = 4 and j = 0. After this operation, word becomes equal to &quot;leetleetleet&quot;.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; ">word = &quot;</span>leetcoleet<span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; ">&quot;, k = 2</span></p> <p><strong>Output:</strong> 3</p> <p><strong>Explanation:</strong></p> <p>We can obtain a 2-periodic string by applying the operations in the table below.</p> <table border="1" bordercolor="#ccc" cellpadding="5" cellspacing="0" height="146" style="border-collapse:collapse; text-align: center; vertical-align: middle;"> <tbody> <tr> <th>i</th> <th>j</th> <th>word</th> </tr> <tr> <td style="padding: 5px 15px;">0</td> <td style="padding: 5px 15px;">2</td> <td style="padding: 5px 15px;">etetcoleet</td> </tr> <tr> <td style="padding: 5px 15px;">4</td> <td style="padding: 5px 15px;">0</td> <td style="padding: 5px 15px;">etetetleet</td> </tr> <tr> <td style="padding: 5px 15px;">6</td> <td style="padding: 5px 15px;">0</td> <td style="padding: 5px 15px;">etetetetet</td> </tr> </tbody> </table> </div> <div id="gtx-trans" style="position: absolute; left: 107px; top: 238.5px;"> <div class="gtx-trans-icon">&nbsp;</div> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == word.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= k &lt;= word.length</code></li> <li><code>k</code> divides <code>word.length</code>.</li> <li><code>word</code> consists only of lowercase English letters.</li> </ul>
Hash Table; String; Counting
Python
class Solution: def minimumOperationsToMakeKPeriodic(self, word: str, k: int) -> int: n = len(word) return n // k - max(Counter(word[i : i + k] for i in range(0, n, k)).values())
3,137
Minimum Number of Operations to Make Word K-Periodic
Medium
<p>You are given a string <code>word</code> of size <code>n</code>, and an integer <code>k</code> such that <code>k</code> divides <code>n</code>.</p> <p>In one operation, you can pick any two indices <code>i</code> and <code>j</code>, that are divisible by <code>k</code>, then replace the <span data-keyword="substring">substring</span> of length <code>k</code> starting at <code>i</code> with the substring of length <code>k</code> starting at <code>j</code>. That is, replace the substring <code>word[i..i + k - 1]</code> with the substring <code>word[j..j + k - 1]</code>.<!-- notionvc: 49ac84f7-0724-452a-ab43-0c5e53f1db33 --></p> <p>Return <em>the <strong>minimum</strong> number of operations required to make</em> <code>word</code> <em><strong>k-periodic</strong></em>.</p> <p>We say that <code>word</code> is <strong>k-periodic</strong> if there is some string <code>s</code> of length <code>k</code> such that <code>word</code> can be obtained by concatenating <code>s</code> an arbitrary number of times. For example, if <code>word == &ldquo;ababab&rdquo;</code>, then <code>word</code> is 2-periodic for <code>s = &quot;ab&quot;</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" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; ">word = &quot;leetcodeleet&quot;, k = 4</span></p> <p><strong>Output:</strong> <span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; ">1</span></p> <p><strong>Explanation:</strong></p> <p>We can obtain a 4-periodic string by picking i = 4 and j = 0. After this operation, word becomes equal to &quot;leetleetleet&quot;.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; ">word = &quot;</span>leetcoleet<span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; ">&quot;, k = 2</span></p> <p><strong>Output:</strong> 3</p> <p><strong>Explanation:</strong></p> <p>We can obtain a 2-periodic string by applying the operations in the table below.</p> <table border="1" bordercolor="#ccc" cellpadding="5" cellspacing="0" height="146" style="border-collapse:collapse; text-align: center; vertical-align: middle;"> <tbody> <tr> <th>i</th> <th>j</th> <th>word</th> </tr> <tr> <td style="padding: 5px 15px;">0</td> <td style="padding: 5px 15px;">2</td> <td style="padding: 5px 15px;">etetcoleet</td> </tr> <tr> <td style="padding: 5px 15px;">4</td> <td style="padding: 5px 15px;">0</td> <td style="padding: 5px 15px;">etetetleet</td> </tr> <tr> <td style="padding: 5px 15px;">6</td> <td style="padding: 5px 15px;">0</td> <td style="padding: 5px 15px;">etetetetet</td> </tr> </tbody> </table> </div> <div id="gtx-trans" style="position: absolute; left: 107px; top: 238.5px;"> <div class="gtx-trans-icon">&nbsp;</div> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n == word.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= k &lt;= word.length</code></li> <li><code>k</code> divides <code>word.length</code>.</li> <li><code>word</code> consists only of lowercase English letters.</li> </ul>
Hash Table; String; Counting
TypeScript
function minimumOperationsToMakeKPeriodic(word: string, k: number): number { const cnt: Map<string, number> = new Map(); const n: number = word.length; let mx: number = 0; for (let i = 0; i < n; i += k) { const s = word.slice(i, i + k); cnt.set(s, (cnt.get(s) || 0) + 1); mx = Math.max(mx, cnt.get(s)!); } return Math.floor(n / k) - mx; }
3,138
Minimum Length of Anagram Concatenation
Medium
<p>You are given a string <code>s</code>, which is known to be a concatenation of <strong>anagrams</strong> of some string <code>t</code>.</p> <p>Return the <strong>minimum</strong> possible length of the string <code>t</code>.</p> <p>An <strong>anagram</strong> is formed by rearranging the letters of a string. For example, &quot;aab&quot;, &quot;aba&quot;, and, &quot;baa&quot; are anagrams of &quot;aab&quot;.</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;abba&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>One possible string <code>t</code> could be <code>&quot;ba&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;cdef&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <p>One possible string <code>t</code> could be <code>&quot;cdef&quot;</code>, notice that <code>t</code> can be equal to <code>s</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;abcbcacabbaccba&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></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</code> consist only of lowercase English letters.</li> </ul>
Hash Table; String; Counting
C++
class Solution { public: int minAnagramLength(string s) { int n = s.size(); int cnt[26]{}; for (char c : s) { cnt[c - 'a']++; } auto check = [&](int k) { for (int i = 0; i < n; i += k) { int cnt1[26]{}; for (int j = i; j < i + k; ++j) { cnt1[s[j] - 'a']++; } for (int j = 0; j < 26; ++j) { if (cnt1[j] * (n / k) != cnt[j]) { return false; } } } return true; }; for (int i = 1;; ++i) { if (n % i == 0 && check(i)) { return i; } } } };
3,138
Minimum Length of Anagram Concatenation
Medium
<p>You are given a string <code>s</code>, which is known to be a concatenation of <strong>anagrams</strong> of some string <code>t</code>.</p> <p>Return the <strong>minimum</strong> possible length of the string <code>t</code>.</p> <p>An <strong>anagram</strong> is formed by rearranging the letters of a string. For example, &quot;aab&quot;, &quot;aba&quot;, and, &quot;baa&quot; are anagrams of &quot;aab&quot;.</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;abba&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>One possible string <code>t</code> could be <code>&quot;ba&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;cdef&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <p>One possible string <code>t</code> could be <code>&quot;cdef&quot;</code>, notice that <code>t</code> can be equal to <code>s</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;abcbcacabbaccba&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></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</code> consist only of lowercase English letters.</li> </ul>
Hash Table; String; Counting
Go
func minAnagramLength(s string) int { n := len(s) cnt := [26]int{} for _, c := range s { cnt[c-'a']++ } check := func(k int) bool { for i := 0; i < n; i += k { cnt1 := [26]int{} for j := i; j < i+k; j++ { cnt1[s[j]-'a']++ } for j, v := range cnt { if cnt1[j]*(n/k) != v { return false } } } return true } for i := 1; ; i++ { if n%i == 0 && check(i) { return i } } }
3,138
Minimum Length of Anagram Concatenation
Medium
<p>You are given a string <code>s</code>, which is known to be a concatenation of <strong>anagrams</strong> of some string <code>t</code>.</p> <p>Return the <strong>minimum</strong> possible length of the string <code>t</code>.</p> <p>An <strong>anagram</strong> is formed by rearranging the letters of a string. For example, &quot;aab&quot;, &quot;aba&quot;, and, &quot;baa&quot; are anagrams of &quot;aab&quot;.</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;abba&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>One possible string <code>t</code> could be <code>&quot;ba&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;cdef&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <p>One possible string <code>t</code> could be <code>&quot;cdef&quot;</code>, notice that <code>t</code> can be equal to <code>s</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;abcbcacabbaccba&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></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</code> consist only of lowercase English letters.</li> </ul>
Hash Table; String; Counting
Java
class Solution { private int n; private char[] s; private int[] cnt = new int[26]; public int minAnagramLength(String s) { n = s.length(); this.s = s.toCharArray(); for (int i = 0; i < n; ++i) { ++cnt[this.s[i] - 'a']; } for (int i = 1;; ++i) { if (n % i == 0 && check(i)) { return i; } } } private boolean check(int k) { for (int i = 0; i < n; i += k) { int[] cnt1 = new int[26]; for (int j = i; j < i + k; ++j) { ++cnt1[s[j] - 'a']; } for (int j = 0; j < 26; ++j) { if (cnt1[j] * (n / k) != cnt[j]) { return false; } } } return true; } }
3,138
Minimum Length of Anagram Concatenation
Medium
<p>You are given a string <code>s</code>, which is known to be a concatenation of <strong>anagrams</strong> of some string <code>t</code>.</p> <p>Return the <strong>minimum</strong> possible length of the string <code>t</code>.</p> <p>An <strong>anagram</strong> is formed by rearranging the letters of a string. For example, &quot;aab&quot;, &quot;aba&quot;, and, &quot;baa&quot; are anagrams of &quot;aab&quot;.</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;abba&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>One possible string <code>t</code> could be <code>&quot;ba&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;cdef&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <p>One possible string <code>t</code> could be <code>&quot;cdef&quot;</code>, notice that <code>t</code> can be equal to <code>s</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;abcbcacabbaccba&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></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</code> consist only of lowercase English letters.</li> </ul>
Hash Table; String; Counting
Python
class Solution: def minAnagramLength(self, s: str) -> int: def check(k: int) -> bool: for i in range(0, n, k): cnt1 = Counter(s[i : i + k]) for c, v in cnt.items(): if cnt1[c] * (n // k) != v: return False return True cnt = Counter(s) n = len(s) for i in range(1, n + 1): if n % i == 0 and check(i): return i
3,138
Minimum Length of Anagram Concatenation
Medium
<p>You are given a string <code>s</code>, which is known to be a concatenation of <strong>anagrams</strong> of some string <code>t</code>.</p> <p>Return the <strong>minimum</strong> possible length of the string <code>t</code>.</p> <p>An <strong>anagram</strong> is formed by rearranging the letters of a string. For example, &quot;aab&quot;, &quot;aba&quot;, and, &quot;baa&quot; are anagrams of &quot;aab&quot;.</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;abba&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>One possible string <code>t</code> could be <code>&quot;ba&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;cdef&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <p>One possible string <code>t</code> could be <code>&quot;cdef&quot;</code>, notice that <code>t</code> can be equal to <code>s</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;abcbcacabbaccba&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></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</code> consist only of lowercase English letters.</li> </ul>
Hash Table; String; Counting
TypeScript
function minAnagramLength(s: string): number { const n = s.length; const cnt: Record<string, number> = {}; for (let i = 0; i < n; i++) { cnt[s[i]] = (cnt[s[i]] || 0) + 1; } const check = (k: number): boolean => { for (let i = 0; i < n; i += k) { const cnt1: Record<string, number> = {}; for (let j = i; j < i + k; j++) { cnt1[s[j]] = (cnt1[s[j]] || 0) + 1; } for (const [c, v] of Object.entries(cnt)) { if (cnt1[c] * ((n / k) | 0) !== v) { return false; } } } return true; }; for (let i = 1; ; ++i) { if (n % i === 0 && check(i)) { return i; } } }
3,140
Consecutive Available Seats II
Medium
<p>Table: <code>Cinema</code></p> <pre> +-------------+------+ | Column Name | Type | +-------------+------+ | seat_id | int | | free | bool | +-------------+------+ seat_id is an auto-increment column for this table. Each row of this table indicates whether the i<sup>th</sup> seat is free or not. 1 means free while 0 means occupied. </pre> <p>Write a solution to find the <strong>length</strong> of&nbsp;<strong>longest consecutive sequence</strong> of <strong>available</strong> seats in the cinema.</p> <p>Note:</p> <ul> <li>There will always be <strong>at most</strong> <strong>one</strong> longest consecutive sequence.</li> <li>If there are <strong>multiple</strong>&nbsp;consecutive sequences with the <strong>same length</strong>, include all of them in the output.</li> </ul> <p>Return <em>the result table <strong>ordered</strong> by</em> <code>first_seat_id</code> <em><strong>in ascending order</strong></em>.</p> <p>The result format is in the following example.</p> <p>&nbsp;</p> <p><strong>Example:</strong></p> <div class="example-block"> <p><strong>Input:</strong></p> <p>Cinema table:</p> <pre class="example-io"> +---------+------+ | seat_id | free | +---------+------+ | 1 | 1 | | 2 | 0 | | 3 | 1 | | 4 | 1 | | 5 | 1 | +---------+------+ </pre> <p><strong>Output:</strong></p> <pre class="example-io"> +-----------------+----------------+-----------------------+ | first_seat_id | last_seat_id | consecutive_seats_len | +-----------------+----------------+-----------------------+ | 3 | 5 | 3 | +-----------------+----------------+-----------------------+ </pre> <p><strong>Explanation:</strong></p> <ul> <li>Longest consecutive sequence of available seats starts from seat 3 and ends at seat 5 with a length of 3.</li> </ul> Output table is ordered by first_seat_id in ascending order.</div>
Database
SQL
# Write your MySQL query statement below WITH T AS ( SELECT *, seat_id - (RANK() OVER (ORDER BY seat_id)) AS gid FROM Cinema WHERE free = 1 ), P AS ( SELECT MIN(seat_id) AS first_seat_id, MAX(seat_id) AS last_seat_id, COUNT(1) AS consecutive_seats_len, RANK() OVER (ORDER BY COUNT(1) DESC) AS rk FROM T GROUP BY gid ) SELECT first_seat_id, last_seat_id, consecutive_seats_len FROM P WHERE rk = 1 ORDER BY 1;
3,141
Maximum Hamming Distances
Hard
<p>Given an array <code>nums</code> and an integer <code>m</code>, with each element <code>nums[i]</code> satisfying <code>0 &lt;= nums[i] &lt; 2<sup>m</sup></code>, return an array <code>answer</code>. The <code>answer</code> array should be of the same length as <code>nums</code>, where each element <code>answer[i]</code> represents the <em>maximum</em> <strong>Hamming distance </strong>between <code>nums[i]</code> and any other element <code>nums[j]</code> in the array.</p> <p>The <strong>Hamming distance</strong> between two binary integers is defined as the number of positions at which the corresponding bits differ (add leading zeroes if needed).</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 = [9,12,9,11], m = 4</span></p> <p><strong>Output:</strong> <span class="example-io">[2,3,2,3]</span></p> <p><strong>Explanation:</strong></p> <p>The binary representation of <code>nums = [1001,1100,1001,1011]</code>.</p> <p>The maximum hamming distances for each index are:</p> <ul> <li><code>nums[0]</code>: 1001 and 1100 have a distance of 2.</li> <li><code>nums[1]</code>: 1100 and 1011 have a distance of 3.</li> <li><code>nums[2]</code>: 1001 and 1100 have a distance of 2.</li> <li><code>nums[3]</code>: 1011 and 1100 have a distance of 3.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [3,4,6,10], m = 4</span></p> <p><strong>Output:</strong> <span class="example-io">[3,3,2,3]</span></p> <p><strong>Explanation:</strong></p> <p>The binary representation of <code>nums = [0011,0100,0110,1010]</code>.</p> <p>The maximum hamming distances for each index are:</p> <ul> <li><code>nums[0]</code>: 0011 and 0100 have a distance of 3.</li> <li><code>nums[1]</code>: 0100 and 0011 have a distance of 3.</li> <li><code>nums[2]</code>: 0110 and 1010 have a distance of 2.</li> <li><code>nums[3]</code>: 1010 and 0100 have a distance of 3.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= m &lt;= 17</code></li> <li><code>2 &lt;= nums.length &lt;= 2<sup>m</sup></code></li> <li><code>0 &lt;= nums[i] &lt; 2<sup>m</sup></code></li> </ul>
Bit Manipulation; Breadth-First Search; Array
C++
class Solution { public: vector<int> maxHammingDistances(vector<int>& nums, int m) { int dist[1 << m]; memset(dist, -1, sizeof(dist)); queue<int> q; for (int x : nums) { dist[x] = 0; q.push(x); } for (int k = 1; q.size(); ++k) { for (int t = q.size(); t; --t) { int x = q.front(); q.pop(); for (int i = 0; i < m; ++i) { int y = x ^ (1 << i); if (dist[y] == -1) { dist[y] = k; q.push(y); } } } } for (int& x : nums) { x = m - dist[x ^ ((1 << m) - 1)]; } return nums; } };
3,141
Maximum Hamming Distances
Hard
<p>Given an array <code>nums</code> and an integer <code>m</code>, with each element <code>nums[i]</code> satisfying <code>0 &lt;= nums[i] &lt; 2<sup>m</sup></code>, return an array <code>answer</code>. The <code>answer</code> array should be of the same length as <code>nums</code>, where each element <code>answer[i]</code> represents the <em>maximum</em> <strong>Hamming distance </strong>between <code>nums[i]</code> and any other element <code>nums[j]</code> in the array.</p> <p>The <strong>Hamming distance</strong> between two binary integers is defined as the number of positions at which the corresponding bits differ (add leading zeroes if needed).</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 = [9,12,9,11], m = 4</span></p> <p><strong>Output:</strong> <span class="example-io">[2,3,2,3]</span></p> <p><strong>Explanation:</strong></p> <p>The binary representation of <code>nums = [1001,1100,1001,1011]</code>.</p> <p>The maximum hamming distances for each index are:</p> <ul> <li><code>nums[0]</code>: 1001 and 1100 have a distance of 2.</li> <li><code>nums[1]</code>: 1100 and 1011 have a distance of 3.</li> <li><code>nums[2]</code>: 1001 and 1100 have a distance of 2.</li> <li><code>nums[3]</code>: 1011 and 1100 have a distance of 3.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [3,4,6,10], m = 4</span></p> <p><strong>Output:</strong> <span class="example-io">[3,3,2,3]</span></p> <p><strong>Explanation:</strong></p> <p>The binary representation of <code>nums = [0011,0100,0110,1010]</code>.</p> <p>The maximum hamming distances for each index are:</p> <ul> <li><code>nums[0]</code>: 0011 and 0100 have a distance of 3.</li> <li><code>nums[1]</code>: 0100 and 0011 have a distance of 3.</li> <li><code>nums[2]</code>: 0110 and 1010 have a distance of 2.</li> <li><code>nums[3]</code>: 1010 and 0100 have a distance of 3.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= m &lt;= 17</code></li> <li><code>2 &lt;= nums.length &lt;= 2<sup>m</sup></code></li> <li><code>0 &lt;= nums[i] &lt; 2<sup>m</sup></code></li> </ul>
Bit Manipulation; Breadth-First Search; Array
Go
func maxHammingDistances(nums []int, m int) []int { dist := make([]int, 1<<m) for i := range dist { dist[i] = -1 } q := []int{} for _, x := range nums { dist[x] = 0 q = append(q, x) } for k := 1; len(q) > 0; k++ { t := []int{} for _, x := range q { for i := 0; i < m; i++ { y := x ^ (1 << i) if dist[y] == -1 { dist[y] = k t = append(t, y) } } } q = t } for i, x := range nums { nums[i] = m - dist[x^(1<<m-1)] } return nums }
3,141
Maximum Hamming Distances
Hard
<p>Given an array <code>nums</code> and an integer <code>m</code>, with each element <code>nums[i]</code> satisfying <code>0 &lt;= nums[i] &lt; 2<sup>m</sup></code>, return an array <code>answer</code>. The <code>answer</code> array should be of the same length as <code>nums</code>, where each element <code>answer[i]</code> represents the <em>maximum</em> <strong>Hamming distance </strong>between <code>nums[i]</code> and any other element <code>nums[j]</code> in the array.</p> <p>The <strong>Hamming distance</strong> between two binary integers is defined as the number of positions at which the corresponding bits differ (add leading zeroes if needed).</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 = [9,12,9,11], m = 4</span></p> <p><strong>Output:</strong> <span class="example-io">[2,3,2,3]</span></p> <p><strong>Explanation:</strong></p> <p>The binary representation of <code>nums = [1001,1100,1001,1011]</code>.</p> <p>The maximum hamming distances for each index are:</p> <ul> <li><code>nums[0]</code>: 1001 and 1100 have a distance of 2.</li> <li><code>nums[1]</code>: 1100 and 1011 have a distance of 3.</li> <li><code>nums[2]</code>: 1001 and 1100 have a distance of 2.</li> <li><code>nums[3]</code>: 1011 and 1100 have a distance of 3.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [3,4,6,10], m = 4</span></p> <p><strong>Output:</strong> <span class="example-io">[3,3,2,3]</span></p> <p><strong>Explanation:</strong></p> <p>The binary representation of <code>nums = [0011,0100,0110,1010]</code>.</p> <p>The maximum hamming distances for each index are:</p> <ul> <li><code>nums[0]</code>: 0011 and 0100 have a distance of 3.</li> <li><code>nums[1]</code>: 0100 and 0011 have a distance of 3.</li> <li><code>nums[2]</code>: 0110 and 1010 have a distance of 2.</li> <li><code>nums[3]</code>: 1010 and 0100 have a distance of 3.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= m &lt;= 17</code></li> <li><code>2 &lt;= nums.length &lt;= 2<sup>m</sup></code></li> <li><code>0 &lt;= nums[i] &lt; 2<sup>m</sup></code></li> </ul>
Bit Manipulation; Breadth-First Search; Array
Java
class Solution { public int[] maxHammingDistances(int[] nums, int m) { int[] dist = new int[1 << m]; Arrays.fill(dist, -1); Deque<Integer> q = new ArrayDeque<>(); for (int x : nums) { dist[x] = 0; q.offer(x); } for (int k = 1; !q.isEmpty(); ++k) { for (int t = q.size(); t > 0; --t) { int x = q.poll(); for (int i = 0; i < m; ++i) { int y = x ^ (1 << i); if (dist[y] == -1) { q.offer(y); dist[y] = k; } } } } for (int i = 0; i < nums.length; ++i) { nums[i] = m - dist[nums[i] ^ ((1 << m) - 1)]; } return nums; } }
3,141
Maximum Hamming Distances
Hard
<p>Given an array <code>nums</code> and an integer <code>m</code>, with each element <code>nums[i]</code> satisfying <code>0 &lt;= nums[i] &lt; 2<sup>m</sup></code>, return an array <code>answer</code>. The <code>answer</code> array should be of the same length as <code>nums</code>, where each element <code>answer[i]</code> represents the <em>maximum</em> <strong>Hamming distance </strong>between <code>nums[i]</code> and any other element <code>nums[j]</code> in the array.</p> <p>The <strong>Hamming distance</strong> between two binary integers is defined as the number of positions at which the corresponding bits differ (add leading zeroes if needed).</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 = [9,12,9,11], m = 4</span></p> <p><strong>Output:</strong> <span class="example-io">[2,3,2,3]</span></p> <p><strong>Explanation:</strong></p> <p>The binary representation of <code>nums = [1001,1100,1001,1011]</code>.</p> <p>The maximum hamming distances for each index are:</p> <ul> <li><code>nums[0]</code>: 1001 and 1100 have a distance of 2.</li> <li><code>nums[1]</code>: 1100 and 1011 have a distance of 3.</li> <li><code>nums[2]</code>: 1001 and 1100 have a distance of 2.</li> <li><code>nums[3]</code>: 1011 and 1100 have a distance of 3.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [3,4,6,10], m = 4</span></p> <p><strong>Output:</strong> <span class="example-io">[3,3,2,3]</span></p> <p><strong>Explanation:</strong></p> <p>The binary representation of <code>nums = [0011,0100,0110,1010]</code>.</p> <p>The maximum hamming distances for each index are:</p> <ul> <li><code>nums[0]</code>: 0011 and 0100 have a distance of 3.</li> <li><code>nums[1]</code>: 0100 and 0011 have a distance of 3.</li> <li><code>nums[2]</code>: 0110 and 1010 have a distance of 2.</li> <li><code>nums[3]</code>: 1010 and 0100 have a distance of 3.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= m &lt;= 17</code></li> <li><code>2 &lt;= nums.length &lt;= 2<sup>m</sup></code></li> <li><code>0 &lt;= nums[i] &lt; 2<sup>m</sup></code></li> </ul>
Bit Manipulation; Breadth-First Search; Array
Python
class Solution: def maxHammingDistances(self, nums: List[int], m: int) -> List[int]: dist = [-1] * (1 << m) for x in nums: dist[x] = 0 q = nums k = 1 while q: t = [] for x in q: for i in range(m): y = x ^ (1 << i) if dist[y] == -1: t.append(y) dist[y] = k q = t k += 1 return [m - dist[x ^ ((1 << m) - 1)] for x in nums]
3,141
Maximum Hamming Distances
Hard
<p>Given an array <code>nums</code> and an integer <code>m</code>, with each element <code>nums[i]</code> satisfying <code>0 &lt;= nums[i] &lt; 2<sup>m</sup></code>, return an array <code>answer</code>. The <code>answer</code> array should be of the same length as <code>nums</code>, where each element <code>answer[i]</code> represents the <em>maximum</em> <strong>Hamming distance </strong>between <code>nums[i]</code> and any other element <code>nums[j]</code> in the array.</p> <p>The <strong>Hamming distance</strong> between two binary integers is defined as the number of positions at which the corresponding bits differ (add leading zeroes if needed).</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 = [9,12,9,11], m = 4</span></p> <p><strong>Output:</strong> <span class="example-io">[2,3,2,3]</span></p> <p><strong>Explanation:</strong></p> <p>The binary representation of <code>nums = [1001,1100,1001,1011]</code>.</p> <p>The maximum hamming distances for each index are:</p> <ul> <li><code>nums[0]</code>: 1001 and 1100 have a distance of 2.</li> <li><code>nums[1]</code>: 1100 and 1011 have a distance of 3.</li> <li><code>nums[2]</code>: 1001 and 1100 have a distance of 2.</li> <li><code>nums[3]</code>: 1011 and 1100 have a distance of 3.</li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [3,4,6,10], m = 4</span></p> <p><strong>Output:</strong> <span class="example-io">[3,3,2,3]</span></p> <p><strong>Explanation:</strong></p> <p>The binary representation of <code>nums = [0011,0100,0110,1010]</code>.</p> <p>The maximum hamming distances for each index are:</p> <ul> <li><code>nums[0]</code>: 0011 and 0100 have a distance of 3.</li> <li><code>nums[1]</code>: 0100 and 0011 have a distance of 3.</li> <li><code>nums[2]</code>: 0110 and 1010 have a distance of 2.</li> <li><code>nums[3]</code>: 1010 and 0100 have a distance of 3.</li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= m &lt;= 17</code></li> <li><code>2 &lt;= nums.length &lt;= 2<sup>m</sup></code></li> <li><code>0 &lt;= nums[i] &lt; 2<sup>m</sup></code></li> </ul>
Bit Manipulation; Breadth-First Search; Array
TypeScript
function maxHammingDistances(nums: number[], m: number): number[] { const dist: number[] = Array.from({ length: 1 << m }, () => -1); const q: number[] = []; for (const x of nums) { dist[x] = 0; q.push(x); } for (let k = 1; q.length; ++k) { const t: number[] = []; for (const x of q) { for (let i = 0; i < m; ++i) { const y = x ^ (1 << i); if (dist[y] === -1) { dist[y] = k; t.push(y); } } } q.splice(0, q.length, ...t); } for (let i = 0; i < nums.length; ++i) { nums[i] = m - dist[nums[i] ^ ((1 << m) - 1)]; } return nums; }
3,142
Check if Grid Satisfies Conditions
Easy
<p>You are given a 2D matrix <code>grid</code> of size <code>m x n</code>. You need to check if each cell <code>grid[i][j]</code> is:</p> <ul> <li>Equal to the cell below it, i.e. <code>grid[i][j] == grid[i + 1][j]</code> (if it exists).</li> <li>Different from the cell to its right, i.e. <code>grid[i][j] != grid[i][j + 1]</code> (if it exists).</li> </ul> <p>Return <code>true</code> if <strong>all</strong> the cells satisfy these conditions, otherwise, return <code>false</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">grid = [[1,0,2],[1,0,2]]</span></p> <p><strong>Output:</strong> <span class="example-io">true</span></p> <p><strong>Explanation:</strong></p> <p><strong><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3142.Check%20if%20Grid%20Satisfies%20Conditions/images/examplechanged.png" style="width: 254px; height: 186px;padding: 10px; background: #fff; border-radius: .5rem;" /></strong></p> <p>All the cells in the grid satisfy the conditions.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">grid = [[1,1,1],[0,0,0]]</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p><strong><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3142.Check%20if%20Grid%20Satisfies%20Conditions/images/example21.png" style="width: 254px; height: 186px;padding: 10px; background: #fff; border-radius: .5rem;" /></strong></p> <p>All cells in the first row are equal.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">grid = [[1],[2],[3]]</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3142.Check%20if%20Grid%20Satisfies%20Conditions/images/changed.png" style="width: 86px; height: 277px;padding: 10px; background: #fff; border-radius: .5rem;" /></p> <p>Cells in the first column have different values.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n, m &lt;= 10</code></li> <li><code>0 &lt;= grid[i][j] &lt;= 9</code></li> </ul>
Array; Matrix
C++
class Solution { public: bool satisfiesConditions(vector<vector<int>>& grid) { int m = grid.size(), n = grid[0].size(); for (int i = 0; i < m; ++i) { for (int j = 0; j < n; ++j) { if (i + 1 < m && grid[i][j] != grid[i + 1][j]) { return false; } if (j + 1 < n && grid[i][j] == grid[i][j + 1]) { return false; } } } return true; } };
3,142
Check if Grid Satisfies Conditions
Easy
<p>You are given a 2D matrix <code>grid</code> of size <code>m x n</code>. You need to check if each cell <code>grid[i][j]</code> is:</p> <ul> <li>Equal to the cell below it, i.e. <code>grid[i][j] == grid[i + 1][j]</code> (if it exists).</li> <li>Different from the cell to its right, i.e. <code>grid[i][j] != grid[i][j + 1]</code> (if it exists).</li> </ul> <p>Return <code>true</code> if <strong>all</strong> the cells satisfy these conditions, otherwise, return <code>false</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">grid = [[1,0,2],[1,0,2]]</span></p> <p><strong>Output:</strong> <span class="example-io">true</span></p> <p><strong>Explanation:</strong></p> <p><strong><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3142.Check%20if%20Grid%20Satisfies%20Conditions/images/examplechanged.png" style="width: 254px; height: 186px;padding: 10px; background: #fff; border-radius: .5rem;" /></strong></p> <p>All the cells in the grid satisfy the conditions.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">grid = [[1,1,1],[0,0,0]]</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p><strong><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3142.Check%20if%20Grid%20Satisfies%20Conditions/images/example21.png" style="width: 254px; height: 186px;padding: 10px; background: #fff; border-radius: .5rem;" /></strong></p> <p>All cells in the first row are equal.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">grid = [[1],[2],[3]]</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3142.Check%20if%20Grid%20Satisfies%20Conditions/images/changed.png" style="width: 86px; height: 277px;padding: 10px; background: #fff; border-radius: .5rem;" /></p> <p>Cells in the first column have different values.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n, m &lt;= 10</code></li> <li><code>0 &lt;= grid[i][j] &lt;= 9</code></li> </ul>
Array; Matrix
Go
func satisfiesConditions(grid [][]int) bool { m, n := len(grid), len(grid[0]) for i, row := range grid { for j, x := range row { if i+1 < m && x != grid[i+1][j] { return false } if j+1 < n && x == grid[i][j+1] { return false } } } return true }
3,142
Check if Grid Satisfies Conditions
Easy
<p>You are given a 2D matrix <code>grid</code> of size <code>m x n</code>. You need to check if each cell <code>grid[i][j]</code> is:</p> <ul> <li>Equal to the cell below it, i.e. <code>grid[i][j] == grid[i + 1][j]</code> (if it exists).</li> <li>Different from the cell to its right, i.e. <code>grid[i][j] != grid[i][j + 1]</code> (if it exists).</li> </ul> <p>Return <code>true</code> if <strong>all</strong> the cells satisfy these conditions, otherwise, return <code>false</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">grid = [[1,0,2],[1,0,2]]</span></p> <p><strong>Output:</strong> <span class="example-io">true</span></p> <p><strong>Explanation:</strong></p> <p><strong><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3142.Check%20if%20Grid%20Satisfies%20Conditions/images/examplechanged.png" style="width: 254px; height: 186px;padding: 10px; background: #fff; border-radius: .5rem;" /></strong></p> <p>All the cells in the grid satisfy the conditions.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">grid = [[1,1,1],[0,0,0]]</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p><strong><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3142.Check%20if%20Grid%20Satisfies%20Conditions/images/example21.png" style="width: 254px; height: 186px;padding: 10px; background: #fff; border-radius: .5rem;" /></strong></p> <p>All cells in the first row are equal.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">grid = [[1],[2],[3]]</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3142.Check%20if%20Grid%20Satisfies%20Conditions/images/changed.png" style="width: 86px; height: 277px;padding: 10px; background: #fff; border-radius: .5rem;" /></p> <p>Cells in the first column have different values.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n, m &lt;= 10</code></li> <li><code>0 &lt;= grid[i][j] &lt;= 9</code></li> </ul>
Array; Matrix
Java
class Solution { public boolean satisfiesConditions(int[][] grid) { int m = grid.length, n = grid[0].length; for (int i = 0; i < m; ++i) { for (int j = 0; j < n; ++j) { if (i + 1 < m && grid[i][j] != grid[i + 1][j]) { return false; } if (j + 1 < n && grid[i][j] == grid[i][j + 1]) { return false; } } } return true; } }
3,142
Check if Grid Satisfies Conditions
Easy
<p>You are given a 2D matrix <code>grid</code> of size <code>m x n</code>. You need to check if each cell <code>grid[i][j]</code> is:</p> <ul> <li>Equal to the cell below it, i.e. <code>grid[i][j] == grid[i + 1][j]</code> (if it exists).</li> <li>Different from the cell to its right, i.e. <code>grid[i][j] != grid[i][j + 1]</code> (if it exists).</li> </ul> <p>Return <code>true</code> if <strong>all</strong> the cells satisfy these conditions, otherwise, return <code>false</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">grid = [[1,0,2],[1,0,2]]</span></p> <p><strong>Output:</strong> <span class="example-io">true</span></p> <p><strong>Explanation:</strong></p> <p><strong><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3142.Check%20if%20Grid%20Satisfies%20Conditions/images/examplechanged.png" style="width: 254px; height: 186px;padding: 10px; background: #fff; border-radius: .5rem;" /></strong></p> <p>All the cells in the grid satisfy the conditions.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">grid = [[1,1,1],[0,0,0]]</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p><strong><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3142.Check%20if%20Grid%20Satisfies%20Conditions/images/example21.png" style="width: 254px; height: 186px;padding: 10px; background: #fff; border-radius: .5rem;" /></strong></p> <p>All cells in the first row are equal.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">grid = [[1],[2],[3]]</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3142.Check%20if%20Grid%20Satisfies%20Conditions/images/changed.png" style="width: 86px; height: 277px;padding: 10px; background: #fff; border-radius: .5rem;" /></p> <p>Cells in the first column have different values.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n, m &lt;= 10</code></li> <li><code>0 &lt;= grid[i][j] &lt;= 9</code></li> </ul>
Array; Matrix
Python
class Solution: def satisfiesConditions(self, grid: List[List[int]]) -> bool: m, n = len(grid), len(grid[0]) for i, row in enumerate(grid): for j, x in enumerate(row): if i + 1 < m and x != grid[i + 1][j]: return False if j + 1 < n and x == grid[i][j + 1]: return False return True
3,142
Check if Grid Satisfies Conditions
Easy
<p>You are given a 2D matrix <code>grid</code> of size <code>m x n</code>. You need to check if each cell <code>grid[i][j]</code> is:</p> <ul> <li>Equal to the cell below it, i.e. <code>grid[i][j] == grid[i + 1][j]</code> (if it exists).</li> <li>Different from the cell to its right, i.e. <code>grid[i][j] != grid[i][j + 1]</code> (if it exists).</li> </ul> <p>Return <code>true</code> if <strong>all</strong> the cells satisfy these conditions, otherwise, return <code>false</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">grid = [[1,0,2],[1,0,2]]</span></p> <p><strong>Output:</strong> <span class="example-io">true</span></p> <p><strong>Explanation:</strong></p> <p><strong><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3142.Check%20if%20Grid%20Satisfies%20Conditions/images/examplechanged.png" style="width: 254px; height: 186px;padding: 10px; background: #fff; border-radius: .5rem;" /></strong></p> <p>All the cells in the grid satisfy the conditions.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">grid = [[1,1,1],[0,0,0]]</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p><strong><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3142.Check%20if%20Grid%20Satisfies%20Conditions/images/example21.png" style="width: 254px; height: 186px;padding: 10px; background: #fff; border-radius: .5rem;" /></strong></p> <p>All cells in the first row are equal.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">grid = [[1],[2],[3]]</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3142.Check%20if%20Grid%20Satisfies%20Conditions/images/changed.png" style="width: 86px; height: 277px;padding: 10px; background: #fff; border-radius: .5rem;" /></p> <p>Cells in the first column have different values.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= n, m &lt;= 10</code></li> <li><code>0 &lt;= grid[i][j] &lt;= 9</code></li> </ul>
Array; Matrix
TypeScript
function satisfiesConditions(grid: number[][]): boolean { const [m, n] = [grid.length, grid[0].length]; for (let i = 0; i < m; ++i) { for (let j = 0; j < n; ++j) { if (i + 1 < m && grid[i][j] !== grid[i + 1][j]) { return false; } if (j + 1 < n && grid[i][j] === grid[i][j + 1]) { return false; } } } return true; }
3,143
Maximum Points Inside the Square
Medium
<p>You are given a 2D<strong> </strong>array <code>points</code> and a string <code>s</code> where, <code>points[i]</code> represents the coordinates of point <code>i</code>, and <code>s[i]</code> represents the <strong>tag</strong> of point <code>i</code>.</p> <p>A <strong>valid</strong> square is a square centered at the origin <code>(0, 0)</code>, has edges parallel to the axes, and <strong>does not</strong> contain two points with the same tag.</p> <p>Return the <strong>maximum</strong> number of points contained in a <strong>valid</strong> square.</p> <p>Note:</p> <ul> <li>A point is considered to be inside the square if it lies on or within the square&#39;s boundaries.</li> <li>The side length of the square can be zero.</li> </ul> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3143.Maximum%20Points%20Inside%20the%20Square/images/3708-tc1.png" style="width: 303px; height: 303px;" /></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">points = [[2,2],[-1,-2],[-4,4],[-3,1],[3,-3]], s = &quot;abdca&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>The square of side length 4 covers two points <code>points[0]</code> and <code>points[1]</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3143.Maximum%20Points%20Inside%20the%20Square/images/3708-tc2.png" style="width: 302px; height: 302px;" /></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">points = [[1,1],[-2,-2],[-2,2]], s = &quot;abb&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <p>The square of side length 2 covers one point, which is <code>points[0]</code>.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">points = [[1,1],[-1,-1],[2,-2]], s = &quot;ccd&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>It&#39;s impossible to make any valid squares centered at the origin such that it covers only one point among <code>points[0]</code> and <code>points[1]</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length, points.length &lt;= 10<sup>5</sup></code></li> <li><code>points[i].length == 2</code></li> <li><code>-10<sup>9</sup> &lt;= points[i][0], points[i][1] &lt;= 10<sup>9</sup></code></li> <li><code>s.length == points.length</code></li> <li><code>points</code> consists of distinct coordinates.</li> <li><code>s</code> consists only of lowercase English letters.</li> </ul>
Array; Hash Table; String; Binary Search; Sorting
C++
class Solution { public: int maxPointsInsideSquare(vector<vector<int>>& points, string s) { map<int, vector<int>> g; for (int i = 0; i < points.size(); ++i) { auto& p = points[i]; int key = max(abs(p[0]), abs(p[1])); g[key].push_back(i); } bool vis[26]{}; int ans = 0; for (auto& [_, idx] : g) { for (int i : idx) { int j = s[i] - 'a'; if (vis[j]) { return ans; } vis[j] = true; } ans += idx.size(); } return ans; } };
3,143
Maximum Points Inside the Square
Medium
<p>You are given a 2D<strong> </strong>array <code>points</code> and a string <code>s</code> where, <code>points[i]</code> represents the coordinates of point <code>i</code>, and <code>s[i]</code> represents the <strong>tag</strong> of point <code>i</code>.</p> <p>A <strong>valid</strong> square is a square centered at the origin <code>(0, 0)</code>, has edges parallel to the axes, and <strong>does not</strong> contain two points with the same tag.</p> <p>Return the <strong>maximum</strong> number of points contained in a <strong>valid</strong> square.</p> <p>Note:</p> <ul> <li>A point is considered to be inside the square if it lies on or within the square&#39;s boundaries.</li> <li>The side length of the square can be zero.</li> </ul> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3143.Maximum%20Points%20Inside%20the%20Square/images/3708-tc1.png" style="width: 303px; height: 303px;" /></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">points = [[2,2],[-1,-2],[-4,4],[-3,1],[3,-3]], s = &quot;abdca&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>The square of side length 4 covers two points <code>points[0]</code> and <code>points[1]</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3143.Maximum%20Points%20Inside%20the%20Square/images/3708-tc2.png" style="width: 302px; height: 302px;" /></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">points = [[1,1],[-2,-2],[-2,2]], s = &quot;abb&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <p>The square of side length 2 covers one point, which is <code>points[0]</code>.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">points = [[1,1],[-1,-1],[2,-2]], s = &quot;ccd&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>It&#39;s impossible to make any valid squares centered at the origin such that it covers only one point among <code>points[0]</code> and <code>points[1]</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length, points.length &lt;= 10<sup>5</sup></code></li> <li><code>points[i].length == 2</code></li> <li><code>-10<sup>9</sup> &lt;= points[i][0], points[i][1] &lt;= 10<sup>9</sup></code></li> <li><code>s.length == points.length</code></li> <li><code>points</code> consists of distinct coordinates.</li> <li><code>s</code> consists only of lowercase English letters.</li> </ul>
Array; Hash Table; String; Binary Search; Sorting
Go
func maxPointsInsideSquare(points [][]int, s string) (ans int) { g := map[int][]int{} for i, p := range points { key := max(p[0], -p[0], p[1], -p[1]) g[key] = append(g[key], i) } vis := [26]bool{} keys := []int{} for k := range g { keys = append(keys, k) } sort.Ints(keys) for _, k := range keys { idx := g[k] for _, i := range idx { j := s[i] - 'a' if vis[j] { return } vis[j] = true } ans += len(idx) } return }
3,143
Maximum Points Inside the Square
Medium
<p>You are given a 2D<strong> </strong>array <code>points</code> and a string <code>s</code> where, <code>points[i]</code> represents the coordinates of point <code>i</code>, and <code>s[i]</code> represents the <strong>tag</strong> of point <code>i</code>.</p> <p>A <strong>valid</strong> square is a square centered at the origin <code>(0, 0)</code>, has edges parallel to the axes, and <strong>does not</strong> contain two points with the same tag.</p> <p>Return the <strong>maximum</strong> number of points contained in a <strong>valid</strong> square.</p> <p>Note:</p> <ul> <li>A point is considered to be inside the square if it lies on or within the square&#39;s boundaries.</li> <li>The side length of the square can be zero.</li> </ul> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3143.Maximum%20Points%20Inside%20the%20Square/images/3708-tc1.png" style="width: 303px; height: 303px;" /></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">points = [[2,2],[-1,-2],[-4,4],[-3,1],[3,-3]], s = &quot;abdca&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>The square of side length 4 covers two points <code>points[0]</code> and <code>points[1]</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3143.Maximum%20Points%20Inside%20the%20Square/images/3708-tc2.png" style="width: 302px; height: 302px;" /></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">points = [[1,1],[-2,-2],[-2,2]], s = &quot;abb&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <p>The square of side length 2 covers one point, which is <code>points[0]</code>.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">points = [[1,1],[-1,-1],[2,-2]], s = &quot;ccd&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>It&#39;s impossible to make any valid squares centered at the origin such that it covers only one point among <code>points[0]</code> and <code>points[1]</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length, points.length &lt;= 10<sup>5</sup></code></li> <li><code>points[i].length == 2</code></li> <li><code>-10<sup>9</sup> &lt;= points[i][0], points[i][1] &lt;= 10<sup>9</sup></code></li> <li><code>s.length == points.length</code></li> <li><code>points</code> consists of distinct coordinates.</li> <li><code>s</code> consists only of lowercase English letters.</li> </ul>
Array; Hash Table; String; Binary Search; Sorting
Java
class Solution { public int maxPointsInsideSquare(int[][] points, String s) { TreeMap<Integer, List<Integer>> g = new TreeMap<>(); for (int i = 0; i < points.length; ++i) { int x = points[i][0], y = points[i][1]; int key = Math.max(Math.abs(x), Math.abs(y)); g.computeIfAbsent(key, k -> new ArrayList<>()).add(i); } boolean[] vis = new boolean[26]; int ans = 0; for (var idx : g.values()) { for (int i : idx) { int j = s.charAt(i) - 'a'; if (vis[j]) { return ans; } vis[j] = true; } ans += idx.size(); } return ans; } }
3,143
Maximum Points Inside the Square
Medium
<p>You are given a 2D<strong> </strong>array <code>points</code> and a string <code>s</code> where, <code>points[i]</code> represents the coordinates of point <code>i</code>, and <code>s[i]</code> represents the <strong>tag</strong> of point <code>i</code>.</p> <p>A <strong>valid</strong> square is a square centered at the origin <code>(0, 0)</code>, has edges parallel to the axes, and <strong>does not</strong> contain two points with the same tag.</p> <p>Return the <strong>maximum</strong> number of points contained in a <strong>valid</strong> square.</p> <p>Note:</p> <ul> <li>A point is considered to be inside the square if it lies on or within the square&#39;s boundaries.</li> <li>The side length of the square can be zero.</li> </ul> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3143.Maximum%20Points%20Inside%20the%20Square/images/3708-tc1.png" style="width: 303px; height: 303px;" /></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">points = [[2,2],[-1,-2],[-4,4],[-3,1],[3,-3]], s = &quot;abdca&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>The square of side length 4 covers two points <code>points[0]</code> and <code>points[1]</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3143.Maximum%20Points%20Inside%20the%20Square/images/3708-tc2.png" style="width: 302px; height: 302px;" /></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">points = [[1,1],[-2,-2],[-2,2]], s = &quot;abb&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <p>The square of side length 2 covers one point, which is <code>points[0]</code>.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">points = [[1,1],[-1,-1],[2,-2]], s = &quot;ccd&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>It&#39;s impossible to make any valid squares centered at the origin such that it covers only one point among <code>points[0]</code> and <code>points[1]</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length, points.length &lt;= 10<sup>5</sup></code></li> <li><code>points[i].length == 2</code></li> <li><code>-10<sup>9</sup> &lt;= points[i][0], points[i][1] &lt;= 10<sup>9</sup></code></li> <li><code>s.length == points.length</code></li> <li><code>points</code> consists of distinct coordinates.</li> <li><code>s</code> consists only of lowercase English letters.</li> </ul>
Array; Hash Table; String; Binary Search; Sorting
Python
class Solution: def maxPointsInsideSquare(self, points: List[List[int]], s: str) -> int: g = defaultdict(list) for i, (x, y) in enumerate(points): g[max(abs(x), abs(y))].append(i) vis = set() ans = 0 for d in sorted(g): idx = g[d] for i in idx: if s[i] in vis: return ans vis.add(s[i]) ans += len(idx) return ans
3,143
Maximum Points Inside the Square
Medium
<p>You are given a 2D<strong> </strong>array <code>points</code> and a string <code>s</code> where, <code>points[i]</code> represents the coordinates of point <code>i</code>, and <code>s[i]</code> represents the <strong>tag</strong> of point <code>i</code>.</p> <p>A <strong>valid</strong> square is a square centered at the origin <code>(0, 0)</code>, has edges parallel to the axes, and <strong>does not</strong> contain two points with the same tag.</p> <p>Return the <strong>maximum</strong> number of points contained in a <strong>valid</strong> square.</p> <p>Note:</p> <ul> <li>A point is considered to be inside the square if it lies on or within the square&#39;s boundaries.</li> <li>The side length of the square can be zero.</li> </ul> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3143.Maximum%20Points%20Inside%20the%20Square/images/3708-tc1.png" style="width: 303px; height: 303px;" /></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">points = [[2,2],[-1,-2],[-4,4],[-3,1],[3,-3]], s = &quot;abdca&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>The square of side length 4 covers two points <code>points[0]</code> and <code>points[1]</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3143.Maximum%20Points%20Inside%20the%20Square/images/3708-tc2.png" style="width: 302px; height: 302px;" /></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">points = [[1,1],[-2,-2],[-2,2]], s = &quot;abb&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">1</span></p> <p><strong>Explanation:</strong></p> <p>The square of side length 2 covers one point, which is <code>points[0]</code>.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">points = [[1,1],[-1,-1],[2,-2]], s = &quot;ccd&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong></p> <p>It&#39;s impossible to make any valid squares centered at the origin such that it covers only one point among <code>points[0]</code> and <code>points[1]</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length, points.length &lt;= 10<sup>5</sup></code></li> <li><code>points[i].length == 2</code></li> <li><code>-10<sup>9</sup> &lt;= points[i][0], points[i][1] &lt;= 10<sup>9</sup></code></li> <li><code>s.length == points.length</code></li> <li><code>points</code> consists of distinct coordinates.</li> <li><code>s</code> consists only of lowercase English letters.</li> </ul>
Array; Hash Table; String; Binary Search; Sorting
TypeScript
function maxPointsInsideSquare(points: number[][], s: string): number { const n = points.length; const g: Map<number, number[]> = new Map(); for (let i = 0; i < n; ++i) { const [x, y] = points[i]; const key = Math.max(Math.abs(x), Math.abs(y)); if (!g.has(key)) { g.set(key, []); } g.get(key)!.push(i); } const keys = Array.from(g.keys()).sort((a, b) => a - b); const vis: boolean[] = Array(26).fill(false); let ans = 0; for (const key of keys) { const idx = g.get(key)!; for (const i of idx) { const j = s.charCodeAt(i) - 'a'.charCodeAt(0); if (vis[j]) { return ans; } vis[j] = true; } ans += idx.length; } return ans; }
3,144
Minimum Substring Partition of Equal Character Frequency
Medium
<p>Given a string <code>s</code>, you need to partition it into one or more <strong>balanced</strong> <span data-keyword="substring">substrings</span>. For example, if <code>s == &quot;ababcc&quot;</code> then <code>(&quot;abab&quot;, &quot;c&quot;, &quot;c&quot;)</code>, <code>(&quot;ab&quot;, &quot;abc&quot;, &quot;c&quot;)</code>, and <code>(&quot;ababcc&quot;)</code> are all valid partitions, but <code>(&quot;a&quot;, <strong>&quot;bab&quot;</strong>, &quot;cc&quot;)</code>, <code>(<strong>&quot;aba&quot;</strong>, &quot;bc&quot;, &quot;c&quot;)</code>, and <code>(&quot;ab&quot;, <strong>&quot;abcc&quot;</strong>)</code> are not. The unbalanced substrings are bolded.</p> <p>Return the <strong>minimum</strong> number of substrings that you can partition <code>s</code> into.</p> <p><strong>Note:</strong> A <strong>balanced</strong> string is a string where each character in the string occurs the same number of times.</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;fabccddg&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></p> <p><strong>Explanation:</strong></p> <p>We can partition the string <code>s</code> into 3 substrings in one of the following ways: <code>(&quot;fab, &quot;ccdd&quot;, &quot;g&quot;)</code>, or <code>(&quot;fabc&quot;, &quot;cd&quot;, &quot;dg&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;abababaccddb&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>We can partition the string <code>s</code> into 2 substrings like so: <code>(&quot;abab&quot;, &quot;abaccddb&quot;)</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 1000</code></li> <li><code>s</code> consists only of English lowercase letters.</li> </ul>
Hash Table; String; Dynamic Programming; Counting
C++
class Solution { public: int minimumSubstringsInPartition(string s) { int n = s.size(); int f[n]; memset(f, -1, sizeof(f)); auto dfs = [&](this auto&& dfs, int i) -> int { if (i >= n) { return 0; } if (f[i] != -1) { return f[i]; } f[i] = n - i; int cnt[26]{}; unordered_map<int, int> freq; for (int j = i; j < n; ++j) { int k = s[j] - 'a'; if (cnt[k]) { freq[cnt[k]]--; if (freq[cnt[k]] == 0) { freq.erase(cnt[k]); } } ++cnt[k]; ++freq[cnt[k]]; if (freq.size() == 1) { f[i] = min(f[i], 1 + dfs(j + 1)); } } return f[i]; }; return dfs(0); } };
3,144
Minimum Substring Partition of Equal Character Frequency
Medium
<p>Given a string <code>s</code>, you need to partition it into one or more <strong>balanced</strong> <span data-keyword="substring">substrings</span>. For example, if <code>s == &quot;ababcc&quot;</code> then <code>(&quot;abab&quot;, &quot;c&quot;, &quot;c&quot;)</code>, <code>(&quot;ab&quot;, &quot;abc&quot;, &quot;c&quot;)</code>, and <code>(&quot;ababcc&quot;)</code> are all valid partitions, but <code>(&quot;a&quot;, <strong>&quot;bab&quot;</strong>, &quot;cc&quot;)</code>, <code>(<strong>&quot;aba&quot;</strong>, &quot;bc&quot;, &quot;c&quot;)</code>, and <code>(&quot;ab&quot;, <strong>&quot;abcc&quot;</strong>)</code> are not. The unbalanced substrings are bolded.</p> <p>Return the <strong>minimum</strong> number of substrings that you can partition <code>s</code> into.</p> <p><strong>Note:</strong> A <strong>balanced</strong> string is a string where each character in the string occurs the same number of times.</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;fabccddg&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></p> <p><strong>Explanation:</strong></p> <p>We can partition the string <code>s</code> into 3 substrings in one of the following ways: <code>(&quot;fab, &quot;ccdd&quot;, &quot;g&quot;)</code>, or <code>(&quot;fabc&quot;, &quot;cd&quot;, &quot;dg&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;abababaccddb&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>We can partition the string <code>s</code> into 2 substrings like so: <code>(&quot;abab&quot;, &quot;abaccddb&quot;)</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 1000</code></li> <li><code>s</code> consists only of English lowercase letters.</li> </ul>
Hash Table; String; Dynamic Programming; Counting
Go
func minimumSubstringsInPartition(s string) int { n := len(s) f := make([]int, n) for i := range f { f[i] = -1 } var dfs func(int) int dfs = func(i int) int { if i >= n { return 0 } if f[i] != -1 { return f[i] } cnt := [26]int{} freq := map[int]int{} f[i] = n - i for j := i; j < n; j++ { k := int(s[j] - 'a') if cnt[k] > 0 { freq[cnt[k]]-- if freq[cnt[k]] == 0 { delete(freq, cnt[k]) } } cnt[k]++ freq[cnt[k]]++ if len(freq) == 1 { f[i] = min(f[i], 1+dfs(j+1)) } } return f[i] } return dfs(0) }
3,144
Minimum Substring Partition of Equal Character Frequency
Medium
<p>Given a string <code>s</code>, you need to partition it into one or more <strong>balanced</strong> <span data-keyword="substring">substrings</span>. For example, if <code>s == &quot;ababcc&quot;</code> then <code>(&quot;abab&quot;, &quot;c&quot;, &quot;c&quot;)</code>, <code>(&quot;ab&quot;, &quot;abc&quot;, &quot;c&quot;)</code>, and <code>(&quot;ababcc&quot;)</code> are all valid partitions, but <code>(&quot;a&quot;, <strong>&quot;bab&quot;</strong>, &quot;cc&quot;)</code>, <code>(<strong>&quot;aba&quot;</strong>, &quot;bc&quot;, &quot;c&quot;)</code>, and <code>(&quot;ab&quot;, <strong>&quot;abcc&quot;</strong>)</code> are not. The unbalanced substrings are bolded.</p> <p>Return the <strong>minimum</strong> number of substrings that you can partition <code>s</code> into.</p> <p><strong>Note:</strong> A <strong>balanced</strong> string is a string where each character in the string occurs the same number of times.</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;fabccddg&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></p> <p><strong>Explanation:</strong></p> <p>We can partition the string <code>s</code> into 3 substrings in one of the following ways: <code>(&quot;fab, &quot;ccdd&quot;, &quot;g&quot;)</code>, or <code>(&quot;fabc&quot;, &quot;cd&quot;, &quot;dg&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;abababaccddb&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>We can partition the string <code>s</code> into 2 substrings like so: <code>(&quot;abab&quot;, &quot;abaccddb&quot;)</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 1000</code></li> <li><code>s</code> consists only of English lowercase letters.</li> </ul>
Hash Table; String; Dynamic Programming; Counting
Java
class Solution { private int n; private char[] s; private Integer[] f; public int minimumSubstringsInPartition(String s) { n = s.length(); f = new Integer[n]; this.s = s.toCharArray(); return dfs(0); } private int dfs(int i) { if (i >= n) { return 0; } if (f[i] != null) { return f[i]; } int[] cnt = new int[26]; Map<Integer, Integer> freq = new HashMap<>(26); int ans = n - i; for (int j = i; j < n; ++j) { int k = s[j] - 'a'; if (cnt[k] > 0) { if (freq.merge(cnt[k], -1, Integer::sum) == 0) { freq.remove(cnt[k]); } } ++cnt[k]; freq.merge(cnt[k], 1, Integer::sum); if (freq.size() == 1) { ans = Math.min(ans, 1 + dfs(j + 1)); } } return f[i] = ans; } }
3,144
Minimum Substring Partition of Equal Character Frequency
Medium
<p>Given a string <code>s</code>, you need to partition it into one or more <strong>balanced</strong> <span data-keyword="substring">substrings</span>. For example, if <code>s == &quot;ababcc&quot;</code> then <code>(&quot;abab&quot;, &quot;c&quot;, &quot;c&quot;)</code>, <code>(&quot;ab&quot;, &quot;abc&quot;, &quot;c&quot;)</code>, and <code>(&quot;ababcc&quot;)</code> are all valid partitions, but <code>(&quot;a&quot;, <strong>&quot;bab&quot;</strong>, &quot;cc&quot;)</code>, <code>(<strong>&quot;aba&quot;</strong>, &quot;bc&quot;, &quot;c&quot;)</code>, and <code>(&quot;ab&quot;, <strong>&quot;abcc&quot;</strong>)</code> are not. The unbalanced substrings are bolded.</p> <p>Return the <strong>minimum</strong> number of substrings that you can partition <code>s</code> into.</p> <p><strong>Note:</strong> A <strong>balanced</strong> string is a string where each character in the string occurs the same number of times.</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;fabccddg&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></p> <p><strong>Explanation:</strong></p> <p>We can partition the string <code>s</code> into 3 substrings in one of the following ways: <code>(&quot;fab, &quot;ccdd&quot;, &quot;g&quot;)</code>, or <code>(&quot;fabc&quot;, &quot;cd&quot;, &quot;dg&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;abababaccddb&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>We can partition the string <code>s</code> into 2 substrings like so: <code>(&quot;abab&quot;, &quot;abaccddb&quot;)</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 1000</code></li> <li><code>s</code> consists only of English lowercase letters.</li> </ul>
Hash Table; String; Dynamic Programming; Counting
Python
class Solution: def minimumSubstringsInPartition(self, s: str) -> int: @cache def dfs(i: int) -> int: if i >= n: return 0 cnt = defaultdict(int) freq = defaultdict(int) ans = n - i for j in range(i, n): if cnt[s[j]]: freq[cnt[s[j]]] -= 1 if not freq[cnt[s[j]]]: freq.pop(cnt[s[j]]) cnt[s[j]] += 1 freq[cnt[s[j]]] += 1 if len(freq) == 1 and (t := 1 + dfs(j + 1)) < ans: ans = t return ans n = len(s) return dfs(0)
3,144
Minimum Substring Partition of Equal Character Frequency
Medium
<p>Given a string <code>s</code>, you need to partition it into one or more <strong>balanced</strong> <span data-keyword="substring">substrings</span>. For example, if <code>s == &quot;ababcc&quot;</code> then <code>(&quot;abab&quot;, &quot;c&quot;, &quot;c&quot;)</code>, <code>(&quot;ab&quot;, &quot;abc&quot;, &quot;c&quot;)</code>, and <code>(&quot;ababcc&quot;)</code> are all valid partitions, but <code>(&quot;a&quot;, <strong>&quot;bab&quot;</strong>, &quot;cc&quot;)</code>, <code>(<strong>&quot;aba&quot;</strong>, &quot;bc&quot;, &quot;c&quot;)</code>, and <code>(&quot;ab&quot;, <strong>&quot;abcc&quot;</strong>)</code> are not. The unbalanced substrings are bolded.</p> <p>Return the <strong>minimum</strong> number of substrings that you can partition <code>s</code> into.</p> <p><strong>Note:</strong> A <strong>balanced</strong> string is a string where each character in the string occurs the same number of times.</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;fabccddg&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">3</span></p> <p><strong>Explanation:</strong></p> <p>We can partition the string <code>s</code> into 3 substrings in one of the following ways: <code>(&quot;fab, &quot;ccdd&quot;, &quot;g&quot;)</code>, or <code>(&quot;fabc&quot;, &quot;cd&quot;, &quot;dg&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;abababaccddb&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>We can partition the string <code>s</code> into 2 substrings like so: <code>(&quot;abab&quot;, &quot;abaccddb&quot;)</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 1000</code></li> <li><code>s</code> consists only of English lowercase letters.</li> </ul>
Hash Table; String; Dynamic Programming; Counting
TypeScript
function minimumSubstringsInPartition(s: string): number { const n = s.length; const f: number[] = Array(n).fill(-1); const dfs = (i: number): number => { if (i >= n) { return 0; } if (f[i] !== -1) { return f[i]; } const cnt: Map<number, number> = new Map(); const freq: Map<number, number> = new Map(); f[i] = n - i; for (let j = i; j < n; ++j) { const k = s.charCodeAt(j) - 97; if (freq.has(cnt.get(k)!)) { freq.set(cnt.get(k)!, freq.get(cnt.get(k)!)! - 1); if (freq.get(cnt.get(k)!) === 0) { freq.delete(cnt.get(k)!); } } cnt.set(k, (cnt.get(k) || 0) + 1); freq.set(cnt.get(k)!, (freq.get(cnt.get(k)!) || 0) + 1); if (freq.size === 1) { f[i] = Math.min(f[i], 1 + dfs(j + 1)); } } return f[i]; }; return dfs(0); }
3,145
Find Products of Elements of Big Array
Hard
<p>The <strong>powerful array</strong> of a non-negative integer <code>x</code> is defined as the shortest sorted array of powers of two that sum up to <code>x</code>. The table below illustrates examples of how the <strong>powerful array</strong> is determined. It can be proven that the powerful array of <code>x</code> is unique.</p> <table border="1"> <tbody> <tr> <th>num</th> <th>Binary Representation</th> <th>powerful array</th> </tr> <tr> <td>1</td> <td>0000<u>1</u></td> <td>[1]</td> </tr> <tr> <td>8</td> <td>0<u>1</u>000</td> <td>[8]</td> </tr> <tr> <td>10</td> <td>0<u>1</u>0<u>1</u>0</td> <td>[2, 8]</td> </tr> <tr> <td>13</td> <td>0<u>11</u>0<u>1</u></td> <td>[1, 4, 8]</td> </tr> <tr> <td>23</td> <td><u>1</u>0<u>111</u></td> <td>[1, 2, 4, 16]</td> </tr> </tbody> </table> <p>The array <code>big_nums</code> is created by concatenating the <strong>powerful arrays</strong> for every positive integer <code>i</code> in ascending order: 1, 2, 3, and so on. Thus, <code>big_nums</code> begins as <code>[<u>1</u>, <u>2</u>, <u>1, 2</u>, <u>4</u>, <u>1, 4</u>, <u>2, 4</u>, <u>1, 2, 4</u>, <u>8</u>, ...]</code>.</p> <p>You are given a 2D integer matrix <code>queries</code>, where for <code>queries[i] = [from<sub>i</sub>, to<sub>i</sub>, mod<sub>i</sub>]</code> you should calculate <code>(big_nums[from<sub>i</sub>] * big_nums[from<sub>i</sub> + 1] * ... * big_nums[to<sub>i</sub>]) % mod<sub>i</sub></code><!-- notionvc: a71131cc-7b52-4786-9a4b-660d6d864f89 -->.</p> <p>Return an integer array <code>answer</code> such that <code>answer[i]</code> is the answer to the <code>i<sup>th</sup></code> query.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">queries = [[1,3,7]]</span></p> <p><strong>Output:</strong> <span class="example-io">[4]</span></p> <p><strong>Explanation:</strong></p> <p>There is one query.</p> <p><code>big_nums[1..3] = [2,1,2]</code>. The product of them is 4. The result is <code>4 % 7 = 4.</code></p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">queries = [[2,5,3],[7,7,4]]</span></p> <p><strong>Output:</strong> <span class="example-io">[2,2]</span></p> <p><strong>Explanation:</strong></p> <p>There are two queries.</p> <p>First query: <code>big_nums[2..5] = [1,2,4,1]</code>. The product of them is 8. The result is <code>8 % 3 = 2</code>.</p> <p>Second query: <code>big_nums[7] = 2</code>. The result is <code>2 % 4 = 2</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= queries.length &lt;= 500</code></li> <li><code>queries[i].length == 3</code></li> <li><code>0 &lt;= queries[i][0] &lt;= queries[i][1] &lt;= 10<sup>15</sup></code></li> <li><code>1 &lt;= queries[i][2] &lt;= 10<sup>5</sup></code></li> </ul>
Bit Manipulation; Array; Binary Search
C++
using ll = long long; const int m = 50; ll cnt[m + 1]; ll s[m + 1]; ll p = 1; auto init = [] { cnt[0] = 0; s[0] = 0; for (int i = 1; i <= m; ++i) { cnt[i] = cnt[i - 1] * 2 + p; s[i] = s[i - 1] * 2 + p * (i - 1); p *= 2; } return 0; }(); pair<ll, ll> numIdxAndSum(ll x) { ll idx = 0; ll totalSum = 0; while (x > 0) { int i = 63 - __builtin_clzll(x); idx += cnt[i]; totalSum += s[i]; x -= 1LL << i; totalSum += (x + 1) * i; idx += x + 1; } return make_pair(idx, totalSum); } ll f(ll i) { ll l = 0; ll r = 1LL << m; while (l < r) { ll mid = (l + r + 1) >> 1; auto idxAndSum = numIdxAndSum(mid); ll idx = idxAndSum.first; if (idx < i) { l = mid; } else { r = mid - 1; } } auto idxAndSum = numIdxAndSum(l); ll totalSum = idxAndSum.second; ll idx = idxAndSum.first; i -= idx; ll x = l + 1; for (int j = 0; j < i; ++j) { ll y = x & -x; totalSum += __builtin_ctzll(y); x -= y; } return totalSum; } ll 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; } class Solution { public: vector<int> findProductsOfElements(vector<vector<ll>>& queries) { int n = queries.size(); vector<int> ans(n); for (int i = 0; i < n; ++i) { ll left = queries[i][0]; ll right = queries[i][1]; ll mod = queries[i][2]; ll power = f(right + 1) - f(left); ans[i] = static_cast<int>(qpow(2, power, mod)); } return ans; } };
3,145
Find Products of Elements of Big Array
Hard
<p>The <strong>powerful array</strong> of a non-negative integer <code>x</code> is defined as the shortest sorted array of powers of two that sum up to <code>x</code>. The table below illustrates examples of how the <strong>powerful array</strong> is determined. It can be proven that the powerful array of <code>x</code> is unique.</p> <table border="1"> <tbody> <tr> <th>num</th> <th>Binary Representation</th> <th>powerful array</th> </tr> <tr> <td>1</td> <td>0000<u>1</u></td> <td>[1]</td> </tr> <tr> <td>8</td> <td>0<u>1</u>000</td> <td>[8]</td> </tr> <tr> <td>10</td> <td>0<u>1</u>0<u>1</u>0</td> <td>[2, 8]</td> </tr> <tr> <td>13</td> <td>0<u>11</u>0<u>1</u></td> <td>[1, 4, 8]</td> </tr> <tr> <td>23</td> <td><u>1</u>0<u>111</u></td> <td>[1, 2, 4, 16]</td> </tr> </tbody> </table> <p>The array <code>big_nums</code> is created by concatenating the <strong>powerful arrays</strong> for every positive integer <code>i</code> in ascending order: 1, 2, 3, and so on. Thus, <code>big_nums</code> begins as <code>[<u>1</u>, <u>2</u>, <u>1, 2</u>, <u>4</u>, <u>1, 4</u>, <u>2, 4</u>, <u>1, 2, 4</u>, <u>8</u>, ...]</code>.</p> <p>You are given a 2D integer matrix <code>queries</code>, where for <code>queries[i] = [from<sub>i</sub>, to<sub>i</sub>, mod<sub>i</sub>]</code> you should calculate <code>(big_nums[from<sub>i</sub>] * big_nums[from<sub>i</sub> + 1] * ... * big_nums[to<sub>i</sub>]) % mod<sub>i</sub></code><!-- notionvc: a71131cc-7b52-4786-9a4b-660d6d864f89 -->.</p> <p>Return an integer array <code>answer</code> such that <code>answer[i]</code> is the answer to the <code>i<sup>th</sup></code> query.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">queries = [[1,3,7]]</span></p> <p><strong>Output:</strong> <span class="example-io">[4]</span></p> <p><strong>Explanation:</strong></p> <p>There is one query.</p> <p><code>big_nums[1..3] = [2,1,2]</code>. The product of them is 4. The result is <code>4 % 7 = 4.</code></p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">queries = [[2,5,3],[7,7,4]]</span></p> <p><strong>Output:</strong> <span class="example-io">[2,2]</span></p> <p><strong>Explanation:</strong></p> <p>There are two queries.</p> <p>First query: <code>big_nums[2..5] = [1,2,4,1]</code>. The product of them is 8. The result is <code>8 % 3 = 2</code>.</p> <p>Second query: <code>big_nums[7] = 2</code>. The result is <code>2 % 4 = 2</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= queries.length &lt;= 500</code></li> <li><code>queries[i].length == 3</code></li> <li><code>0 &lt;= queries[i][0] &lt;= queries[i][1] &lt;= 10<sup>15</sup></code></li> <li><code>1 &lt;= queries[i][2] &lt;= 10<sup>5</sup></code></li> </ul>
Bit Manipulation; Array; Binary Search
Go
const m = 50 var cnt [m + 1]int64 var s [m + 1]int64 var p int64 = 1 func init() { cnt[0] = 0 s[0] = 0 for i := 1; i <= m; i++ { cnt[i] = cnt[i-1]*2 + p s[i] = s[i-1]*2 + p*(int64(i)-1) p *= 2 } } func numIdxAndSum(x int64) (int64, int64) { var idx, totalSum int64 for x > 0 { i := 63 - bits.LeadingZeros64(uint64(x)) idx += cnt[i] totalSum += s[i] x -= 1 << i totalSum += (x + 1) * int64(i) idx += x + 1 } return idx, totalSum } func f(i int64) int64 { l, r := int64(0), int64(1)<<m for l < r { mid := (l + r + 1) >> 1 idx, _ := numIdxAndSum(mid) if idx < i { l = mid } else { r = mid - 1 } } _, totalSum := numIdxAndSum(l) idx, _ := numIdxAndSum(l) i -= idx x := l + 1 for j := int64(0); j < i; j++ { y := x & -x totalSum += int64(bits.TrailingZeros64(uint64(y))) x -= y } return totalSum } func qpow(a, n, mod int64) int64 { ans := int64(1) % mod a = a % mod for n > 0 { if n&1 == 1 { ans = (ans * a) % mod } a = (a * a) % mod n >>= 1 } return ans } func findProductsOfElements(queries [][]int64) []int { ans := make([]int, len(queries)) for i, q := range queries { left, right, mod := q[0], q[1], q[2] power := f(right+1) - f(left) ans[i] = int(qpow(2, power, mod)) } return ans }
3,145
Find Products of Elements of Big Array
Hard
<p>The <strong>powerful array</strong> of a non-negative integer <code>x</code> is defined as the shortest sorted array of powers of two that sum up to <code>x</code>. The table below illustrates examples of how the <strong>powerful array</strong> is determined. It can be proven that the powerful array of <code>x</code> is unique.</p> <table border="1"> <tbody> <tr> <th>num</th> <th>Binary Representation</th> <th>powerful array</th> </tr> <tr> <td>1</td> <td>0000<u>1</u></td> <td>[1]</td> </tr> <tr> <td>8</td> <td>0<u>1</u>000</td> <td>[8]</td> </tr> <tr> <td>10</td> <td>0<u>1</u>0<u>1</u>0</td> <td>[2, 8]</td> </tr> <tr> <td>13</td> <td>0<u>11</u>0<u>1</u></td> <td>[1, 4, 8]</td> </tr> <tr> <td>23</td> <td><u>1</u>0<u>111</u></td> <td>[1, 2, 4, 16]</td> </tr> </tbody> </table> <p>The array <code>big_nums</code> is created by concatenating the <strong>powerful arrays</strong> for every positive integer <code>i</code> in ascending order: 1, 2, 3, and so on. Thus, <code>big_nums</code> begins as <code>[<u>1</u>, <u>2</u>, <u>1, 2</u>, <u>4</u>, <u>1, 4</u>, <u>2, 4</u>, <u>1, 2, 4</u>, <u>8</u>, ...]</code>.</p> <p>You are given a 2D integer matrix <code>queries</code>, where for <code>queries[i] = [from<sub>i</sub>, to<sub>i</sub>, mod<sub>i</sub>]</code> you should calculate <code>(big_nums[from<sub>i</sub>] * big_nums[from<sub>i</sub> + 1] * ... * big_nums[to<sub>i</sub>]) % mod<sub>i</sub></code><!-- notionvc: a71131cc-7b52-4786-9a4b-660d6d864f89 -->.</p> <p>Return an integer array <code>answer</code> such that <code>answer[i]</code> is the answer to the <code>i<sup>th</sup></code> query.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">queries = [[1,3,7]]</span></p> <p><strong>Output:</strong> <span class="example-io">[4]</span></p> <p><strong>Explanation:</strong></p> <p>There is one query.</p> <p><code>big_nums[1..3] = [2,1,2]</code>. The product of them is 4. The result is <code>4 % 7 = 4.</code></p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">queries = [[2,5,3],[7,7,4]]</span></p> <p><strong>Output:</strong> <span class="example-io">[2,2]</span></p> <p><strong>Explanation:</strong></p> <p>There are two queries.</p> <p>First query: <code>big_nums[2..5] = [1,2,4,1]</code>. The product of them is 8. The result is <code>8 % 3 = 2</code>.</p> <p>Second query: <code>big_nums[7] = 2</code>. The result is <code>2 % 4 = 2</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= queries.length &lt;= 500</code></li> <li><code>queries[i].length == 3</code></li> <li><code>0 &lt;= queries[i][0] &lt;= queries[i][1] &lt;= 10<sup>15</sup></code></li> <li><code>1 &lt;= queries[i][2] &lt;= 10<sup>5</sup></code></li> </ul>
Bit Manipulation; Array; Binary Search
Java
class Solution { private static final int M = 50; private static final long[] cnt = new long[M + 1]; private static final long[] s = new long[M + 1]; static { long p = 1; for (int i = 1; i <= M; i++) { cnt[i] = cnt[i - 1] * 2 + p; s[i] = s[i - 1] * 2 + p * (i - 1); p *= 2; } } private static long[] numIdxAndSum(long x) { long idx = 0; long totalSum = 0; while (x > 0) { int i = Long.SIZE - Long.numberOfLeadingZeros(x) - 1; idx += cnt[i]; totalSum += s[i]; x -= 1L << i; totalSum += (x + 1) * i; idx += x + 1; } return new long[] {idx, totalSum}; } private static long f(long i) { long l = 0; long r = 1L << M; while (l < r) { long mid = (l + r + 1) >> 1; long[] idxAndSum = numIdxAndSum(mid); long idx = idxAndSum[0]; if (idx < i) { l = mid; } else { r = mid - 1; } } long[] idxAndSum = numIdxAndSum(l); long totalSum = idxAndSum[1]; long idx = idxAndSum[0]; i -= idx; long x = l + 1; for (int j = 0; j < i; j++) { long y = x & -x; totalSum += Long.numberOfTrailingZeros(y); x -= y; } return totalSum; } public int[] findProductsOfElements(long[][] queries) { int n = queries.length; int[] ans = new int[n]; for (int i = 0; i < n; i++) { long left = queries[i][0]; long right = queries[i][1]; long mod = queries[i][2]; long power = f(right + 1) - f(left); ans[i] = qpow(2, power, mod); } return ans; } 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; } }
3,145
Find Products of Elements of Big Array
Hard
<p>The <strong>powerful array</strong> of a non-negative integer <code>x</code> is defined as the shortest sorted array of powers of two that sum up to <code>x</code>. The table below illustrates examples of how the <strong>powerful array</strong> is determined. It can be proven that the powerful array of <code>x</code> is unique.</p> <table border="1"> <tbody> <tr> <th>num</th> <th>Binary Representation</th> <th>powerful array</th> </tr> <tr> <td>1</td> <td>0000<u>1</u></td> <td>[1]</td> </tr> <tr> <td>8</td> <td>0<u>1</u>000</td> <td>[8]</td> </tr> <tr> <td>10</td> <td>0<u>1</u>0<u>1</u>0</td> <td>[2, 8]</td> </tr> <tr> <td>13</td> <td>0<u>11</u>0<u>1</u></td> <td>[1, 4, 8]</td> </tr> <tr> <td>23</td> <td><u>1</u>0<u>111</u></td> <td>[1, 2, 4, 16]</td> </tr> </tbody> </table> <p>The array <code>big_nums</code> is created by concatenating the <strong>powerful arrays</strong> for every positive integer <code>i</code> in ascending order: 1, 2, 3, and so on. Thus, <code>big_nums</code> begins as <code>[<u>1</u>, <u>2</u>, <u>1, 2</u>, <u>4</u>, <u>1, 4</u>, <u>2, 4</u>, <u>1, 2, 4</u>, <u>8</u>, ...]</code>.</p> <p>You are given a 2D integer matrix <code>queries</code>, where for <code>queries[i] = [from<sub>i</sub>, to<sub>i</sub>, mod<sub>i</sub>]</code> you should calculate <code>(big_nums[from<sub>i</sub>] * big_nums[from<sub>i</sub> + 1] * ... * big_nums[to<sub>i</sub>]) % mod<sub>i</sub></code><!-- notionvc: a71131cc-7b52-4786-9a4b-660d6d864f89 -->.</p> <p>Return an integer array <code>answer</code> such that <code>answer[i]</code> is the answer to the <code>i<sup>th</sup></code> query.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">queries = [[1,3,7]]</span></p> <p><strong>Output:</strong> <span class="example-io">[4]</span></p> <p><strong>Explanation:</strong></p> <p>There is one query.</p> <p><code>big_nums[1..3] = [2,1,2]</code>. The product of them is 4. The result is <code>4 % 7 = 4.</code></p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">queries = [[2,5,3],[7,7,4]]</span></p> <p><strong>Output:</strong> <span class="example-io">[2,2]</span></p> <p><strong>Explanation:</strong></p> <p>There are two queries.</p> <p>First query: <code>big_nums[2..5] = [1,2,4,1]</code>. The product of them is 8. The result is <code>8 % 3 = 2</code>.</p> <p>Second query: <code>big_nums[7] = 2</code>. The result is <code>2 % 4 = 2</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= queries.length &lt;= 500</code></li> <li><code>queries[i].length == 3</code></li> <li><code>0 &lt;= queries[i][0] &lt;= queries[i][1] &lt;= 10<sup>15</sup></code></li> <li><code>1 &lt;= queries[i][2] &lt;= 10<sup>5</sup></code></li> </ul>
Bit Manipulation; Array; Binary Search
Python
m = 50 cnt = [0] * (m + 1) s = [0] * (m + 1) p = 1 for i in range(1, m + 1): cnt[i] = cnt[i - 1] * 2 + p s[i] = s[i - 1] * 2 + p * (i - 1) p *= 2 def num_idx_and_sum(x: int) -> tuple: idx = 0 total_sum = 0 while x: i = x.bit_length() - 1 idx += cnt[i] total_sum += s[i] x -= 1 << i total_sum += (x + 1) * i idx += x + 1 return (idx, total_sum) def f(i: int) -> int: l, r = 0, 1 << m while l < r: mid = (l + r + 1) >> 1 idx, _ = num_idx_and_sum(mid) if idx < i: l = mid else: r = mid - 1 total_sum = 0 idx, total_sum = num_idx_and_sum(l) i -= idx x = l + 1 for _ in range(i): y = x & -x total_sum += y.bit_length() - 1 x -= y return total_sum class Solution: def findProductsOfElements(self, queries: List[List[int]]) -> List[int]: return [pow(2, f(right + 1) - f(left), mod) for left, right, mod in queries]
3,146
Permutation Difference between Two Strings
Easy
<p>You are given two strings <code>s</code> and <code>t</code> such that every character occurs at most once in <code>s</code> and <code>t</code> is a permutation of <code>s</code>.</p> <p>The <strong>permutation difference</strong> between <code>s</code> and <code>t</code> is defined as the <strong>sum</strong> of the absolute difference between the index of the occurrence of each character in <code>s</code> and the index of the occurrence of the same character in <code>t</code>.</p> <p>Return the <strong>permutation difference</strong> between <code>s</code> and <code>t</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;abc&quot;, t = &quot;bac&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>For <code>s = &quot;abc&quot;</code> and <code>t = &quot;bac&quot;</code>, the permutation difference of <code>s</code> and <code>t</code> is equal to the sum of:</p> <ul> <li>The absolute difference between the index of the occurrence of <code>&quot;a&quot;</code> in <code>s</code> and the index of the occurrence of <code>&quot;a&quot;</code> in <code>t</code>.</li> <li>The absolute difference between the index of the occurrence of <code>&quot;b&quot;</code> in <code>s</code> and the index of the occurrence of <code>&quot;b&quot;</code> in <code>t</code>.</li> <li>The absolute difference between the index of the occurrence of <code>&quot;c&quot;</code> in <code>s</code> and the index of the occurrence of <code>&quot;c&quot;</code> in <code>t</code>.</li> </ul> <p>That is, the permutation difference between <code>s</code> and <code>t</code> is equal to <code>|0 - 1| + |1 - 0| + |2 - 2| = 2</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;abcde&quot;, t = &quot;edbac&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">12</span></p> <p><strong>Explanation:</strong> The permutation difference between <code>s</code> and <code>t</code> is equal to <code>|0 - 3| + |1 - 2| + |2 - 4| + |3 - 1| + |4 - 0| = 12</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 26</code></li> <li>Each character occurs at most once in <code>s</code>.</li> <li><code>t</code> is a permutation of <code>s</code>.</li> <li><code>s</code> consists only of lowercase English letters.</li> </ul>
Hash Table; String
C++
class Solution { public: int findPermutationDifference(string s, string t) { int d[26]{}; int n = s.size(); for (int i = 0; i < n; ++i) { d[s[i] - 'a'] = i; } int ans = 0; for (int i = 0; i < n; ++i) { ans += abs(d[t[i] - 'a'] - i); } return ans; } };
3,146
Permutation Difference between Two Strings
Easy
<p>You are given two strings <code>s</code> and <code>t</code> such that every character occurs at most once in <code>s</code> and <code>t</code> is a permutation of <code>s</code>.</p> <p>The <strong>permutation difference</strong> between <code>s</code> and <code>t</code> is defined as the <strong>sum</strong> of the absolute difference between the index of the occurrence of each character in <code>s</code> and the index of the occurrence of the same character in <code>t</code>.</p> <p>Return the <strong>permutation difference</strong> between <code>s</code> and <code>t</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;abc&quot;, t = &quot;bac&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>For <code>s = &quot;abc&quot;</code> and <code>t = &quot;bac&quot;</code>, the permutation difference of <code>s</code> and <code>t</code> is equal to the sum of:</p> <ul> <li>The absolute difference between the index of the occurrence of <code>&quot;a&quot;</code> in <code>s</code> and the index of the occurrence of <code>&quot;a&quot;</code> in <code>t</code>.</li> <li>The absolute difference between the index of the occurrence of <code>&quot;b&quot;</code> in <code>s</code> and the index of the occurrence of <code>&quot;b&quot;</code> in <code>t</code>.</li> <li>The absolute difference between the index of the occurrence of <code>&quot;c&quot;</code> in <code>s</code> and the index of the occurrence of <code>&quot;c&quot;</code> in <code>t</code>.</li> </ul> <p>That is, the permutation difference between <code>s</code> and <code>t</code> is equal to <code>|0 - 1| + |1 - 0| + |2 - 2| = 2</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;abcde&quot;, t = &quot;edbac&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">12</span></p> <p><strong>Explanation:</strong> The permutation difference between <code>s</code> and <code>t</code> is equal to <code>|0 - 3| + |1 - 2| + |2 - 4| + |3 - 1| + |4 - 0| = 12</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 26</code></li> <li>Each character occurs at most once in <code>s</code>.</li> <li><code>t</code> is a permutation of <code>s</code>.</li> <li><code>s</code> consists only of lowercase English letters.</li> </ul>
Hash Table; String
C#
public class Solution { public int FindPermutationDifference(string s, string t) { int[] d = new int[26]; int n = s.Length; for (int i = 0; i < n; ++i) { d[s[i] - 'a'] = i; } int ans = 0; for (int i = 0; i < n; ++i) { ans += Math.Abs(d[t[i] - 'a'] - i); } return ans; } }
3,146
Permutation Difference between Two Strings
Easy
<p>You are given two strings <code>s</code> and <code>t</code> such that every character occurs at most once in <code>s</code> and <code>t</code> is a permutation of <code>s</code>.</p> <p>The <strong>permutation difference</strong> between <code>s</code> and <code>t</code> is defined as the <strong>sum</strong> of the absolute difference between the index of the occurrence of each character in <code>s</code> and the index of the occurrence of the same character in <code>t</code>.</p> <p>Return the <strong>permutation difference</strong> between <code>s</code> and <code>t</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;abc&quot;, t = &quot;bac&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>For <code>s = &quot;abc&quot;</code> and <code>t = &quot;bac&quot;</code>, the permutation difference of <code>s</code> and <code>t</code> is equal to the sum of:</p> <ul> <li>The absolute difference between the index of the occurrence of <code>&quot;a&quot;</code> in <code>s</code> and the index of the occurrence of <code>&quot;a&quot;</code> in <code>t</code>.</li> <li>The absolute difference between the index of the occurrence of <code>&quot;b&quot;</code> in <code>s</code> and the index of the occurrence of <code>&quot;b&quot;</code> in <code>t</code>.</li> <li>The absolute difference between the index of the occurrence of <code>&quot;c&quot;</code> in <code>s</code> and the index of the occurrence of <code>&quot;c&quot;</code> in <code>t</code>.</li> </ul> <p>That is, the permutation difference between <code>s</code> and <code>t</code> is equal to <code>|0 - 1| + |1 - 0| + |2 - 2| = 2</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;abcde&quot;, t = &quot;edbac&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">12</span></p> <p><strong>Explanation:</strong> The permutation difference between <code>s</code> and <code>t</code> is equal to <code>|0 - 3| + |1 - 2| + |2 - 4| + |3 - 1| + |4 - 0| = 12</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 26</code></li> <li>Each character occurs at most once in <code>s</code>.</li> <li><code>t</code> is a permutation of <code>s</code>.</li> <li><code>s</code> consists only of lowercase English letters.</li> </ul>
Hash Table; String
Go
func findPermutationDifference(s string, t string) (ans int) { d := [26]int{} for i, c := range s { d[c-'a'] = i } for i, c := range t { ans += max(d[c-'a']-i, i-d[c-'a']) } return }
3,146
Permutation Difference between Two Strings
Easy
<p>You are given two strings <code>s</code> and <code>t</code> such that every character occurs at most once in <code>s</code> and <code>t</code> is a permutation of <code>s</code>.</p> <p>The <strong>permutation difference</strong> between <code>s</code> and <code>t</code> is defined as the <strong>sum</strong> of the absolute difference between the index of the occurrence of each character in <code>s</code> and the index of the occurrence of the same character in <code>t</code>.</p> <p>Return the <strong>permutation difference</strong> between <code>s</code> and <code>t</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;abc&quot;, t = &quot;bac&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>For <code>s = &quot;abc&quot;</code> and <code>t = &quot;bac&quot;</code>, the permutation difference of <code>s</code> and <code>t</code> is equal to the sum of:</p> <ul> <li>The absolute difference between the index of the occurrence of <code>&quot;a&quot;</code> in <code>s</code> and the index of the occurrence of <code>&quot;a&quot;</code> in <code>t</code>.</li> <li>The absolute difference between the index of the occurrence of <code>&quot;b&quot;</code> in <code>s</code> and the index of the occurrence of <code>&quot;b&quot;</code> in <code>t</code>.</li> <li>The absolute difference between the index of the occurrence of <code>&quot;c&quot;</code> in <code>s</code> and the index of the occurrence of <code>&quot;c&quot;</code> in <code>t</code>.</li> </ul> <p>That is, the permutation difference between <code>s</code> and <code>t</code> is equal to <code>|0 - 1| + |1 - 0| + |2 - 2| = 2</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;abcde&quot;, t = &quot;edbac&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">12</span></p> <p><strong>Explanation:</strong> The permutation difference between <code>s</code> and <code>t</code> is equal to <code>|0 - 3| + |1 - 2| + |2 - 4| + |3 - 1| + |4 - 0| = 12</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 26</code></li> <li>Each character occurs at most once in <code>s</code>.</li> <li><code>t</code> is a permutation of <code>s</code>.</li> <li><code>s</code> consists only of lowercase English letters.</li> </ul>
Hash Table; String
Java
class Solution { public int findPermutationDifference(String s, String t) { int[] d = new int[26]; int n = s.length(); for (int i = 0; i < n; ++i) { d[s.charAt(i) - 'a'] = i; } int ans = 0; for (int i = 0; i < n; ++i) { ans += Math.abs(d[t.charAt(i) - 'a'] - i); } return ans; } }
3,146
Permutation Difference between Two Strings
Easy
<p>You are given two strings <code>s</code> and <code>t</code> such that every character occurs at most once in <code>s</code> and <code>t</code> is a permutation of <code>s</code>.</p> <p>The <strong>permutation difference</strong> between <code>s</code> and <code>t</code> is defined as the <strong>sum</strong> of the absolute difference between the index of the occurrence of each character in <code>s</code> and the index of the occurrence of the same character in <code>t</code>.</p> <p>Return the <strong>permutation difference</strong> between <code>s</code> and <code>t</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;abc&quot;, t = &quot;bac&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>For <code>s = &quot;abc&quot;</code> and <code>t = &quot;bac&quot;</code>, the permutation difference of <code>s</code> and <code>t</code> is equal to the sum of:</p> <ul> <li>The absolute difference between the index of the occurrence of <code>&quot;a&quot;</code> in <code>s</code> and the index of the occurrence of <code>&quot;a&quot;</code> in <code>t</code>.</li> <li>The absolute difference between the index of the occurrence of <code>&quot;b&quot;</code> in <code>s</code> and the index of the occurrence of <code>&quot;b&quot;</code> in <code>t</code>.</li> <li>The absolute difference between the index of the occurrence of <code>&quot;c&quot;</code> in <code>s</code> and the index of the occurrence of <code>&quot;c&quot;</code> in <code>t</code>.</li> </ul> <p>That is, the permutation difference between <code>s</code> and <code>t</code> is equal to <code>|0 - 1| + |1 - 0| + |2 - 2| = 2</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;abcde&quot;, t = &quot;edbac&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">12</span></p> <p><strong>Explanation:</strong> The permutation difference between <code>s</code> and <code>t</code> is equal to <code>|0 - 3| + |1 - 2| + |2 - 4| + |3 - 1| + |4 - 0| = 12</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 26</code></li> <li>Each character occurs at most once in <code>s</code>.</li> <li><code>t</code> is a permutation of <code>s</code>.</li> <li><code>s</code> consists only of lowercase English letters.</li> </ul>
Hash Table; String
Python
class Solution: def findPermutationDifference(self, s: str, t: str) -> int: d = {c: i for i, c in enumerate(s)} return sum(abs(d[c] - i) for i, c in enumerate(t))
3,146
Permutation Difference between Two Strings
Easy
<p>You are given two strings <code>s</code> and <code>t</code> such that every character occurs at most once in <code>s</code> and <code>t</code> is a permutation of <code>s</code>.</p> <p>The <strong>permutation difference</strong> between <code>s</code> and <code>t</code> is defined as the <strong>sum</strong> of the absolute difference between the index of the occurrence of each character in <code>s</code> and the index of the occurrence of the same character in <code>t</code>.</p> <p>Return the <strong>permutation difference</strong> between <code>s</code> and <code>t</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;abc&quot;, t = &quot;bac&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>For <code>s = &quot;abc&quot;</code> and <code>t = &quot;bac&quot;</code>, the permutation difference of <code>s</code> and <code>t</code> is equal to the sum of:</p> <ul> <li>The absolute difference between the index of the occurrence of <code>&quot;a&quot;</code> in <code>s</code> and the index of the occurrence of <code>&quot;a&quot;</code> in <code>t</code>.</li> <li>The absolute difference between the index of the occurrence of <code>&quot;b&quot;</code> in <code>s</code> and the index of the occurrence of <code>&quot;b&quot;</code> in <code>t</code>.</li> <li>The absolute difference between the index of the occurrence of <code>&quot;c&quot;</code> in <code>s</code> and the index of the occurrence of <code>&quot;c&quot;</code> in <code>t</code>.</li> </ul> <p>That is, the permutation difference between <code>s</code> and <code>t</code> is equal to <code>|0 - 1| + |1 - 0| + |2 - 2| = 2</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;abcde&quot;, t = &quot;edbac&quot;</span></p> <p><strong>Output:</strong> <span class="example-io">12</span></p> <p><strong>Explanation:</strong> The permutation difference between <code>s</code> and <code>t</code> is equal to <code>|0 - 3| + |1 - 2| + |2 - 4| + |3 - 1| + |4 - 0| = 12</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= s.length &lt;= 26</code></li> <li>Each character occurs at most once in <code>s</code>.</li> <li><code>t</code> is a permutation of <code>s</code>.</li> <li><code>s</code> consists only of lowercase English letters.</li> </ul>
Hash Table; String
TypeScript
function findPermutationDifference(s: string, t: string): number { const d: number[] = Array(26).fill(0); const n = s.length; for (let i = 0; i < n; ++i) { d[s.charCodeAt(i) - 97] = i; } let ans = 0; for (let i = 0; i < n; ++i) { ans += Math.abs(d[t.charCodeAt(i) - 97] - i); } return ans; }
3,147
Taking Maximum Energy From the Mystic Dungeon
Medium
<p>In a mystic dungeon, <code>n</code> magicians are standing in a line. Each magician has an attribute that gives you energy. Some magicians can give you negative energy, which means taking energy from you.</p> <p>You have been cursed in such a way that after absorbing energy from magician <code>i</code>, you will be instantly transported to magician <code>(i + k)</code>. This process will be repeated until you reach the magician where <code>(i + k)</code> does not exist.</p> <p>In other words, you will choose a starting point and then teleport with <code>k</code> jumps until you reach the end of the magicians&#39; sequence, <strong>absorbing all the energy</strong> during the journey.</p> <p>You are given an array <code>energy</code> and an integer <code>k</code>. Return the <strong>maximum</strong> possible energy you can gain.</p> <p><strong>Note</strong> that when you are reach a magician, you <em>must</em> take energy from them, whether it is negative or positive energy.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block" style=" border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem; "> <p><strong>Input:</strong> <span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; "> energy = [5,2,-10,-5,1], k = 3</span></p> <p><strong>Output:</strong><span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; "> 3</span></p> <p><strong>Explanation:</strong> We can gain a total energy of 3 by starting from magician 1 absorbing 2 + 1 = 3.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block" style=" border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem; "> <p><strong>Input:</strong><span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; "> energy = [-2,-3,-1], k = 2</span></p> <p><strong>Output:</strong><span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; "> -1</span></p> <p><strong>Explanation:</strong> We can gain a total energy of -1 by starting from magician 2.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= energy.length &lt;= 10<sup>5</sup></code></li> <li><code>-1000 &lt;= energy[i] &lt;= 1000</code></li> <li><code>1 &lt;= k &lt;= energy.length - 1</code></li> </ul> <p>&nbsp;</p> ​​​​​​
Array; Prefix Sum
C++
class Solution { public: int maximumEnergy(vector<int>& energy, int k) { int ans = -(1 << 30); int n = energy.size(); for (int i = n - k; i < n; ++i) { for (int j = i, s = 0; j >= 0; j -= k) { s += energy[j]; ans = max(ans, s); } } return ans; } };
3,147
Taking Maximum Energy From the Mystic Dungeon
Medium
<p>In a mystic dungeon, <code>n</code> magicians are standing in a line. Each magician has an attribute that gives you energy. Some magicians can give you negative energy, which means taking energy from you.</p> <p>You have been cursed in such a way that after absorbing energy from magician <code>i</code>, you will be instantly transported to magician <code>(i + k)</code>. This process will be repeated until you reach the magician where <code>(i + k)</code> does not exist.</p> <p>In other words, you will choose a starting point and then teleport with <code>k</code> jumps until you reach the end of the magicians&#39; sequence, <strong>absorbing all the energy</strong> during the journey.</p> <p>You are given an array <code>energy</code> and an integer <code>k</code>. Return the <strong>maximum</strong> possible energy you can gain.</p> <p><strong>Note</strong> that when you are reach a magician, you <em>must</em> take energy from them, whether it is negative or positive energy.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block" style=" border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem; "> <p><strong>Input:</strong> <span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; "> energy = [5,2,-10,-5,1], k = 3</span></p> <p><strong>Output:</strong><span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; "> 3</span></p> <p><strong>Explanation:</strong> We can gain a total energy of 3 by starting from magician 1 absorbing 2 + 1 = 3.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block" style=" border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem; "> <p><strong>Input:</strong><span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; "> energy = [-2,-3,-1], k = 2</span></p> <p><strong>Output:</strong><span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; "> -1</span></p> <p><strong>Explanation:</strong> We can gain a total energy of -1 by starting from magician 2.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= energy.length &lt;= 10<sup>5</sup></code></li> <li><code>-1000 &lt;= energy[i] &lt;= 1000</code></li> <li><code>1 &lt;= k &lt;= energy.length - 1</code></li> </ul> <p>&nbsp;</p> ​​​​​​
Array; Prefix Sum
Go
func maximumEnergy(energy []int, k int) int { ans := -(1 << 30) n := len(energy) for i := n - k; i < n; i++ { for j, s := i, 0; j >= 0; j -= k { s += energy[j] ans = max(ans, s) } } return ans }
3,147
Taking Maximum Energy From the Mystic Dungeon
Medium
<p>In a mystic dungeon, <code>n</code> magicians are standing in a line. Each magician has an attribute that gives you energy. Some magicians can give you negative energy, which means taking energy from you.</p> <p>You have been cursed in such a way that after absorbing energy from magician <code>i</code>, you will be instantly transported to magician <code>(i + k)</code>. This process will be repeated until you reach the magician where <code>(i + k)</code> does not exist.</p> <p>In other words, you will choose a starting point and then teleport with <code>k</code> jumps until you reach the end of the magicians&#39; sequence, <strong>absorbing all the energy</strong> during the journey.</p> <p>You are given an array <code>energy</code> and an integer <code>k</code>. Return the <strong>maximum</strong> possible energy you can gain.</p> <p><strong>Note</strong> that when you are reach a magician, you <em>must</em> take energy from them, whether it is negative or positive energy.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block" style=" border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem; "> <p><strong>Input:</strong> <span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; "> energy = [5,2,-10,-5,1], k = 3</span></p> <p><strong>Output:</strong><span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; "> 3</span></p> <p><strong>Explanation:</strong> We can gain a total energy of 3 by starting from magician 1 absorbing 2 + 1 = 3.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block" style=" border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem; "> <p><strong>Input:</strong><span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; "> energy = [-2,-3,-1], k = 2</span></p> <p><strong>Output:</strong><span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; "> -1</span></p> <p><strong>Explanation:</strong> We can gain a total energy of -1 by starting from magician 2.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= energy.length &lt;= 10<sup>5</sup></code></li> <li><code>-1000 &lt;= energy[i] &lt;= 1000</code></li> <li><code>1 &lt;= k &lt;= energy.length - 1</code></li> </ul> <p>&nbsp;</p> ​​​​​​
Array; Prefix Sum
Java
class Solution { public int maximumEnergy(int[] energy, int k) { int ans = -(1 << 30); int n = energy.length; for (int i = n - k; i < n; ++i) { for (int j = i, s = 0; j >= 0; j -= k) { s += energy[j]; ans = Math.max(ans, s); } } return ans; } }
3,147
Taking Maximum Energy From the Mystic Dungeon
Medium
<p>In a mystic dungeon, <code>n</code> magicians are standing in a line. Each magician has an attribute that gives you energy. Some magicians can give you negative energy, which means taking energy from you.</p> <p>You have been cursed in such a way that after absorbing energy from magician <code>i</code>, you will be instantly transported to magician <code>(i + k)</code>. This process will be repeated until you reach the magician where <code>(i + k)</code> does not exist.</p> <p>In other words, you will choose a starting point and then teleport with <code>k</code> jumps until you reach the end of the magicians&#39; sequence, <strong>absorbing all the energy</strong> during the journey.</p> <p>You are given an array <code>energy</code> and an integer <code>k</code>. Return the <strong>maximum</strong> possible energy you can gain.</p> <p><strong>Note</strong> that when you are reach a magician, you <em>must</em> take energy from them, whether it is negative or positive energy.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block" style=" border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem; "> <p><strong>Input:</strong> <span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; "> energy = [5,2,-10,-5,1], k = 3</span></p> <p><strong>Output:</strong><span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; "> 3</span></p> <p><strong>Explanation:</strong> We can gain a total energy of 3 by starting from magician 1 absorbing 2 + 1 = 3.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block" style=" border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem; "> <p><strong>Input:</strong><span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; "> energy = [-2,-3,-1], k = 2</span></p> <p><strong>Output:</strong><span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; "> -1</span></p> <p><strong>Explanation:</strong> We can gain a total energy of -1 by starting from magician 2.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= energy.length &lt;= 10<sup>5</sup></code></li> <li><code>-1000 &lt;= energy[i] &lt;= 1000</code></li> <li><code>1 &lt;= k &lt;= energy.length - 1</code></li> </ul> <p>&nbsp;</p> ​​​​​​
Array; Prefix Sum
Python
class Solution: def maximumEnergy(self, energy: List[int], k: int) -> int: ans = -inf n = len(energy) for i in range(n - k, n): j, s = i, 0 while j >= 0: s += energy[j] ans = max(ans, s) j -= k return ans
3,147
Taking Maximum Energy From the Mystic Dungeon
Medium
<p>In a mystic dungeon, <code>n</code> magicians are standing in a line. Each magician has an attribute that gives you energy. Some magicians can give you negative energy, which means taking energy from you.</p> <p>You have been cursed in such a way that after absorbing energy from magician <code>i</code>, you will be instantly transported to magician <code>(i + k)</code>. This process will be repeated until you reach the magician where <code>(i + k)</code> does not exist.</p> <p>In other words, you will choose a starting point and then teleport with <code>k</code> jumps until you reach the end of the magicians&#39; sequence, <strong>absorbing all the energy</strong> during the journey.</p> <p>You are given an array <code>energy</code> and an integer <code>k</code>. Return the <strong>maximum</strong> possible energy you can gain.</p> <p><strong>Note</strong> that when you are reach a magician, you <em>must</em> take energy from them, whether it is negative or positive energy.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block" style=" border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem; "> <p><strong>Input:</strong> <span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; "> energy = [5,2,-10,-5,1], k = 3</span></p> <p><strong>Output:</strong><span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; "> 3</span></p> <p><strong>Explanation:</strong> We can gain a total energy of 3 by starting from magician 1 absorbing 2 + 1 = 3.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block" style=" border-color: var(--border-tertiary); border-left-width: 2px; color: var(--text-secondary); font-size: .875rem; margin-bottom: 1rem; margin-top: 1rem; overflow: visible; padding-left: 1rem; "> <p><strong>Input:</strong><span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; "> energy = [-2,-3,-1], k = 2</span></p> <p><strong>Output:</strong><span class="example-io" style=" font-family: Menlo,sans-serif; font-size: 0.85rem; "> -1</span></p> <p><strong>Explanation:</strong> We can gain a total energy of -1 by starting from magician 2.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= energy.length &lt;= 10<sup>5</sup></code></li> <li><code>-1000 &lt;= energy[i] &lt;= 1000</code></li> <li><code>1 &lt;= k &lt;= energy.length - 1</code></li> </ul> <p>&nbsp;</p> ​​​​​​
Array; Prefix Sum
TypeScript
function maximumEnergy(energy: number[], k: number): number { const n = energy.length; let ans = -Infinity; for (let i = n - k; i < n; ++i) { for (let j = i, s = 0; j >= 0; j -= k) { s += energy[j]; ans = Math.max(ans, s); } } return ans; }
3,148
Maximum Difference Score in a Grid
Medium
<p>You are given an <code>m x n</code> matrix <code>grid</code> consisting of <strong>positive</strong> integers. You can move from a cell in the matrix to <strong>any</strong> other cell that is either to the bottom or to the right (not necessarily adjacent). The score of a move from a cell with the value <code>c1</code> to a cell with the value <code>c2</code> is <code>c2 - c1</code>.<!-- notionvc: 8819ca04-8606-4ecf-815b-fb77bc63b851 --></p> <p>You can start at <strong>any</strong> cell, and you have to make <strong>at least</strong> one move.</p> <p>Return the <strong>maximum</strong> total score you can achieve.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3148.Maximum%20Difference%20Score%20in%20a%20Grid/images/grid1.png" style="width: 240px; height: 240px;" /> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">grid = [[9,5,7,3],[8,9,6,1],[6,7,14,3],[2,5,3,1]]</span></p> <p><strong>Output:</strong> <span class="example-io">9</span></p> <p><strong>Explanation:</strong> We start at the cell <code>(0, 1)</code>, and we perform the following moves:<br /> - Move from the cell <code>(0, 1)</code> to <code>(2, 1)</code> with a score of <code>7 - 5 = 2</code>.<br /> - Move from the cell <code>(2, 1)</code> to <code>(2, 2)</code> with a score of <code>14 - 7 = 7</code>.<br /> The total score is <code>2 + 7 = 9</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3148.Maximum%20Difference%20Score%20in%20a%20Grid/images/moregridsdrawio-1.png" style="width: 180px; height: 116px;" /></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">grid = [[4,3,2],[3,2,1]]</span></p> <p><strong>Output:</strong> <span class="example-io">-1</span></p> <p><strong>Explanation:</strong> We start at the cell <code>(0, 0)</code>, and we perform one move: <code>(0, 0)</code> to <code>(0, 1)</code>. The score is <code>3 - 4 = -1</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>m == grid.length</code></li> <li><code>n == grid[i].length</code></li> <li><code>2 &lt;= m, n &lt;= 1000</code></li> <li><code>4 &lt;= m * n &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= grid[i][j] &lt;= 10<sup>5</sup></code></li> </ul>
Array; Dynamic Programming; Matrix
C++
class Solution { public: int maxScore(vector<vector<int>>& grid) { int m = grid.size(), n = grid[0].size(); const int inf = 1 << 30; int ans = -inf; int f[m][n]; for (int i = 0; i < m; ++i) { for (int j = 0; j < n; ++j) { int mi = inf; if (i) { mi = min(mi, f[i - 1][j]); } if (j) { mi = min(mi, f[i][j - 1]); } ans = max(ans, grid[i][j] - mi); f[i][j] = min(grid[i][j], mi); } } return ans; } };
3,148
Maximum Difference Score in a Grid
Medium
<p>You are given an <code>m x n</code> matrix <code>grid</code> consisting of <strong>positive</strong> integers. You can move from a cell in the matrix to <strong>any</strong> other cell that is either to the bottom or to the right (not necessarily adjacent). The score of a move from a cell with the value <code>c1</code> to a cell with the value <code>c2</code> is <code>c2 - c1</code>.<!-- notionvc: 8819ca04-8606-4ecf-815b-fb77bc63b851 --></p> <p>You can start at <strong>any</strong> cell, and you have to make <strong>at least</strong> one move.</p> <p>Return the <strong>maximum</strong> total score you can achieve.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3148.Maximum%20Difference%20Score%20in%20a%20Grid/images/grid1.png" style="width: 240px; height: 240px;" /> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">grid = [[9,5,7,3],[8,9,6,1],[6,7,14,3],[2,5,3,1]]</span></p> <p><strong>Output:</strong> <span class="example-io">9</span></p> <p><strong>Explanation:</strong> We start at the cell <code>(0, 1)</code>, and we perform the following moves:<br /> - Move from the cell <code>(0, 1)</code> to <code>(2, 1)</code> with a score of <code>7 - 5 = 2</code>.<br /> - Move from the cell <code>(2, 1)</code> to <code>(2, 2)</code> with a score of <code>14 - 7 = 7</code>.<br /> The total score is <code>2 + 7 = 9</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3148.Maximum%20Difference%20Score%20in%20a%20Grid/images/moregridsdrawio-1.png" style="width: 180px; height: 116px;" /></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">grid = [[4,3,2],[3,2,1]]</span></p> <p><strong>Output:</strong> <span class="example-io">-1</span></p> <p><strong>Explanation:</strong> We start at the cell <code>(0, 0)</code>, and we perform one move: <code>(0, 0)</code> to <code>(0, 1)</code>. The score is <code>3 - 4 = -1</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>m == grid.length</code></li> <li><code>n == grid[i].length</code></li> <li><code>2 &lt;= m, n &lt;= 1000</code></li> <li><code>4 &lt;= m * n &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= grid[i][j] &lt;= 10<sup>5</sup></code></li> </ul>
Array; Dynamic Programming; Matrix
Go
func maxScore(grid [][]int) int { m, n := len(grid), len(grid[0]) f := make([][]int, m) for i := range f { f[i] = make([]int, n) } const inf int = 1 << 30 ans := -inf for i, row := range grid { for j, x := range row { mi := inf if i > 0 { mi = min(mi, f[i-1][j]) } if j > 0 { mi = min(mi, f[i][j-1]) } ans = max(ans, x-mi) f[i][j] = min(x, mi) } } return ans }
3,148
Maximum Difference Score in a Grid
Medium
<p>You are given an <code>m x n</code> matrix <code>grid</code> consisting of <strong>positive</strong> integers. You can move from a cell in the matrix to <strong>any</strong> other cell that is either to the bottom or to the right (not necessarily adjacent). The score of a move from a cell with the value <code>c1</code> to a cell with the value <code>c2</code> is <code>c2 - c1</code>.<!-- notionvc: 8819ca04-8606-4ecf-815b-fb77bc63b851 --></p> <p>You can start at <strong>any</strong> cell, and you have to make <strong>at least</strong> one move.</p> <p>Return the <strong>maximum</strong> total score you can achieve.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3148.Maximum%20Difference%20Score%20in%20a%20Grid/images/grid1.png" style="width: 240px; height: 240px;" /> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">grid = [[9,5,7,3],[8,9,6,1],[6,7,14,3],[2,5,3,1]]</span></p> <p><strong>Output:</strong> <span class="example-io">9</span></p> <p><strong>Explanation:</strong> We start at the cell <code>(0, 1)</code>, and we perform the following moves:<br /> - Move from the cell <code>(0, 1)</code> to <code>(2, 1)</code> with a score of <code>7 - 5 = 2</code>.<br /> - Move from the cell <code>(2, 1)</code> to <code>(2, 2)</code> with a score of <code>14 - 7 = 7</code>.<br /> The total score is <code>2 + 7 = 9</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3148.Maximum%20Difference%20Score%20in%20a%20Grid/images/moregridsdrawio-1.png" style="width: 180px; height: 116px;" /></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">grid = [[4,3,2],[3,2,1]]</span></p> <p><strong>Output:</strong> <span class="example-io">-1</span></p> <p><strong>Explanation:</strong> We start at the cell <code>(0, 0)</code>, and we perform one move: <code>(0, 0)</code> to <code>(0, 1)</code>. The score is <code>3 - 4 = -1</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>m == grid.length</code></li> <li><code>n == grid[i].length</code></li> <li><code>2 &lt;= m, n &lt;= 1000</code></li> <li><code>4 &lt;= m * n &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= grid[i][j] &lt;= 10<sup>5</sup></code></li> </ul>
Array; Dynamic Programming; Matrix
Java
class Solution { public int maxScore(List<List<Integer>> grid) { int m = grid.size(), n = grid.get(0).size(); final int inf = 1 << 30; int ans = -inf; int[][] f = new int[m][n]; for (int i = 0; i < m; ++i) { for (int j = 0; j < n; ++j) { int mi = inf; if (i > 0) { mi = Math.min(mi, f[i - 1][j]); } if (j > 0) { mi = Math.min(mi, f[i][j - 1]); } ans = Math.max(ans, grid.get(i).get(j) - mi); f[i][j] = Math.min(grid.get(i).get(j), mi); } } return ans; } }
3,148
Maximum Difference Score in a Grid
Medium
<p>You are given an <code>m x n</code> matrix <code>grid</code> consisting of <strong>positive</strong> integers. You can move from a cell in the matrix to <strong>any</strong> other cell that is either to the bottom or to the right (not necessarily adjacent). The score of a move from a cell with the value <code>c1</code> to a cell with the value <code>c2</code> is <code>c2 - c1</code>.<!-- notionvc: 8819ca04-8606-4ecf-815b-fb77bc63b851 --></p> <p>You can start at <strong>any</strong> cell, and you have to make <strong>at least</strong> one move.</p> <p>Return the <strong>maximum</strong> total score you can achieve.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3148.Maximum%20Difference%20Score%20in%20a%20Grid/images/grid1.png" style="width: 240px; height: 240px;" /> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">grid = [[9,5,7,3],[8,9,6,1],[6,7,14,3],[2,5,3,1]]</span></p> <p><strong>Output:</strong> <span class="example-io">9</span></p> <p><strong>Explanation:</strong> We start at the cell <code>(0, 1)</code>, and we perform the following moves:<br /> - Move from the cell <code>(0, 1)</code> to <code>(2, 1)</code> with a score of <code>7 - 5 = 2</code>.<br /> - Move from the cell <code>(2, 1)</code> to <code>(2, 2)</code> with a score of <code>14 - 7 = 7</code>.<br /> The total score is <code>2 + 7 = 9</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3148.Maximum%20Difference%20Score%20in%20a%20Grid/images/moregridsdrawio-1.png" style="width: 180px; height: 116px;" /></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">grid = [[4,3,2],[3,2,1]]</span></p> <p><strong>Output:</strong> <span class="example-io">-1</span></p> <p><strong>Explanation:</strong> We start at the cell <code>(0, 0)</code>, and we perform one move: <code>(0, 0)</code> to <code>(0, 1)</code>. The score is <code>3 - 4 = -1</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>m == grid.length</code></li> <li><code>n == grid[i].length</code></li> <li><code>2 &lt;= m, n &lt;= 1000</code></li> <li><code>4 &lt;= m * n &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= grid[i][j] &lt;= 10<sup>5</sup></code></li> </ul>
Array; Dynamic Programming; Matrix
Python
class Solution: def maxScore(self, grid: List[List[int]]) -> int: f = [[0] * len(grid[0]) for _ in range(len(grid))] ans = -inf for i, row in enumerate(grid): for j, x in enumerate(row): mi = inf if i: mi = min(mi, f[i - 1][j]) if j: mi = min(mi, f[i][j - 1]) ans = max(ans, x - mi) f[i][j] = min(x, mi) return ans
3,148
Maximum Difference Score in a Grid
Medium
<p>You are given an <code>m x n</code> matrix <code>grid</code> consisting of <strong>positive</strong> integers. You can move from a cell in the matrix to <strong>any</strong> other cell that is either to the bottom or to the right (not necessarily adjacent). The score of a move from a cell with the value <code>c1</code> to a cell with the value <code>c2</code> is <code>c2 - c1</code>.<!-- notionvc: 8819ca04-8606-4ecf-815b-fb77bc63b851 --></p> <p>You can start at <strong>any</strong> cell, and you have to make <strong>at least</strong> one move.</p> <p>Return the <strong>maximum</strong> total score you can achieve.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3148.Maximum%20Difference%20Score%20in%20a%20Grid/images/grid1.png" style="width: 240px; height: 240px;" /> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">grid = [[9,5,7,3],[8,9,6,1],[6,7,14,3],[2,5,3,1]]</span></p> <p><strong>Output:</strong> <span class="example-io">9</span></p> <p><strong>Explanation:</strong> We start at the cell <code>(0, 1)</code>, and we perform the following moves:<br /> - Move from the cell <code>(0, 1)</code> to <code>(2, 1)</code> with a score of <code>7 - 5 = 2</code>.<br /> - Move from the cell <code>(2, 1)</code> to <code>(2, 2)</code> with a score of <code>14 - 7 = 7</code>.<br /> The total score is <code>2 + 7 = 9</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <p><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3148.Maximum%20Difference%20Score%20in%20a%20Grid/images/moregridsdrawio-1.png" style="width: 180px; height: 116px;" /></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">grid = [[4,3,2],[3,2,1]]</span></p> <p><strong>Output:</strong> <span class="example-io">-1</span></p> <p><strong>Explanation:</strong> We start at the cell <code>(0, 0)</code>, and we perform one move: <code>(0, 0)</code> to <code>(0, 1)</code>. The score is <code>3 - 4 = -1</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>m == grid.length</code></li> <li><code>n == grid[i].length</code></li> <li><code>2 &lt;= m, n &lt;= 1000</code></li> <li><code>4 &lt;= m * n &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= grid[i][j] &lt;= 10<sup>5</sup></code></li> </ul>
Array; Dynamic Programming; Matrix
TypeScript
function maxScore(grid: number[][]): number { const [m, n] = [grid.length, grid[0].length]; const f: number[][] = Array.from({ length: m }, () => Array.from({ length: n }, () => 0)); let ans = -Infinity; for (let i = 0; i < m; ++i) { for (let j = 0; j < n; ++j) { let mi = Infinity; if (i) { mi = Math.min(mi, f[i - 1][j]); } if (j) { mi = Math.min(mi, f[i][j - 1]); } ans = Math.max(ans, grid[i][j] - mi); f[i][j] = Math.min(mi, grid[i][j]); } } return ans; }
3,149
Find the Minimum Cost Array Permutation
Hard
<p>You are given an array <code>nums</code> which is a <span data-keyword="permutation">permutation</span> of <code>[0, 1, 2, ..., n - 1]</code>. The <strong>score</strong> of any permutation of <code>[0, 1, 2, ..., n - 1]</code> named <code>perm</code> is defined as:</p> <p><code>score(perm) = |perm[0] - nums[perm[1]]| + |perm[1] - nums[perm[2]]| + ... + |perm[n - 1] - nums[perm[0]]|</code></p> <p>Return the permutation <code>perm</code> which has the <strong>minimum</strong> possible score. If <em>multiple</em> permutations exist with this score, return the one that is <span data-keyword="lexicographically-smaller-array">lexicographically smallest</span> among them.</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 = [1,0,2]</span></p> <p><strong>Output:</strong> <span class="example-io">[0,1,2]</span></p> <p><strong>Explanation:</strong></p> <p><strong><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3149.Find%20the%20Minimum%20Cost%20Array%20Permutation/images/example0gif.gif" style="width: 235px; height: 235px;" /></strong></p> <p>The lexicographically smallest permutation with minimum cost is <code>[0,1,2]</code>. The cost of this permutation is <code>|0 - 0| + |1 - 2| + |2 - 1| = 2</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [0,2,1]</span></p> <p><strong>Output:</strong> <span class="example-io">[0,2,1]</span></p> <p><strong>Explanation:</strong></p> <p><strong><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3149.Find%20the%20Minimum%20Cost%20Array%20Permutation/images/example1gif.gif" style="width: 235px; height: 235px;" /></strong></p> <p>The lexicographically smallest permutation with minimum cost is <code>[0,2,1]</code>. The cost of this permutation is <code>|0 - 1| + |2 - 2| + |1 - 0| = 2</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= n == nums.length &lt;= 14</code></li> <li><code>nums</code> is a permutation of <code>[0, 1, 2, ..., n - 1]</code>.</li> </ul>
Bit Manipulation; Array; Dynamic Programming; Bitmask
C++
class Solution { public: vector<int> findPermutation(vector<int>& nums) { int n = nums.size(); vector<int> ans; int f[1 << n][n]; memset(f, -1, sizeof(f)); function<int(int, int)> dfs = [&](int mask, int pre) { if (mask == (1 << n) - 1) { return abs(pre - nums[0]); } int* res = &f[mask][pre]; if (*res != -1) { return *res; } *res = INT_MAX; for (int cur = 1; cur < n; ++cur) { if (mask >> cur & 1 ^ 1) { *res = min(*res, abs(pre - nums[cur]) + dfs(mask | 1 << cur, cur)); } } return *res; }; function<void(int, int)> g = [&](int mask, int pre) { ans.push_back(pre); if (mask == (1 << n) - 1) { return; } int res = dfs(mask, pre); for (int cur = 1; cur < n; ++cur) { if (mask >> cur & 1 ^ 1) { if (abs(pre - nums[cur]) + dfs(mask | 1 << cur, cur) == res) { g(mask | 1 << cur, cur); break; } } } }; g(1, 0); return ans; } };
3,149
Find the Minimum Cost Array Permutation
Hard
<p>You are given an array <code>nums</code> which is a <span data-keyword="permutation">permutation</span> of <code>[0, 1, 2, ..., n - 1]</code>. The <strong>score</strong> of any permutation of <code>[0, 1, 2, ..., n - 1]</code> named <code>perm</code> is defined as:</p> <p><code>score(perm) = |perm[0] - nums[perm[1]]| + |perm[1] - nums[perm[2]]| + ... + |perm[n - 1] - nums[perm[0]]|</code></p> <p>Return the permutation <code>perm</code> which has the <strong>minimum</strong> possible score. If <em>multiple</em> permutations exist with this score, return the one that is <span data-keyword="lexicographically-smaller-array">lexicographically smallest</span> among them.</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 = [1,0,2]</span></p> <p><strong>Output:</strong> <span class="example-io">[0,1,2]</span></p> <p><strong>Explanation:</strong></p> <p><strong><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3149.Find%20the%20Minimum%20Cost%20Array%20Permutation/images/example0gif.gif" style="width: 235px; height: 235px;" /></strong></p> <p>The lexicographically smallest permutation with minimum cost is <code>[0,1,2]</code>. The cost of this permutation is <code>|0 - 0| + |1 - 2| + |2 - 1| = 2</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [0,2,1]</span></p> <p><strong>Output:</strong> <span class="example-io">[0,2,1]</span></p> <p><strong>Explanation:</strong></p> <p><strong><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3149.Find%20the%20Minimum%20Cost%20Array%20Permutation/images/example1gif.gif" style="width: 235px; height: 235px;" /></strong></p> <p>The lexicographically smallest permutation with minimum cost is <code>[0,2,1]</code>. The cost of this permutation is <code>|0 - 1| + |2 - 2| + |1 - 0| = 2</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= n == nums.length &lt;= 14</code></li> <li><code>nums</code> is a permutation of <code>[0, 1, 2, ..., n - 1]</code>.</li> </ul>
Bit Manipulation; Array; Dynamic Programming; Bitmask
Go
func findPermutation(nums []int) (ans []int) { n := len(nums) f := make([][]int, 1<<n) for i := range f { f[i] = make([]int, n) for j := range f[i] { f[i][j] = -1 } } var dfs func(int, int) int dfs = func(mask, pre int) int { if mask == 1<<n-1 { return abs(pre - nums[0]) } if f[mask][pre] != -1 { return f[mask][pre] } res := &f[mask][pre] *res = math.MaxInt32 for cur := 1; cur < n; cur++ { if mask>>cur&1 == 0 { *res = min(*res, abs(pre-nums[cur])+dfs(mask|1<<cur, cur)) } } return *res } var g func(int, int) g = func(mask, pre int) { ans = append(ans, pre) if mask == 1<<n-1 { return } res := dfs(mask, pre) for cur := 1; cur < n; cur++ { if mask>>cur&1 == 0 { if abs(pre-nums[cur])+dfs(mask|1<<cur, cur) == res { g(mask|1<<cur, cur) break } } } } g(1, 0) return } func abs(x int) int { if x < 0 { return -x } return x }
3,149
Find the Minimum Cost Array Permutation
Hard
<p>You are given an array <code>nums</code> which is a <span data-keyword="permutation">permutation</span> of <code>[0, 1, 2, ..., n - 1]</code>. The <strong>score</strong> of any permutation of <code>[0, 1, 2, ..., n - 1]</code> named <code>perm</code> is defined as:</p> <p><code>score(perm) = |perm[0] - nums[perm[1]]| + |perm[1] - nums[perm[2]]| + ... + |perm[n - 1] - nums[perm[0]]|</code></p> <p>Return the permutation <code>perm</code> which has the <strong>minimum</strong> possible score. If <em>multiple</em> permutations exist with this score, return the one that is <span data-keyword="lexicographically-smaller-array">lexicographically smallest</span> among them.</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 = [1,0,2]</span></p> <p><strong>Output:</strong> <span class="example-io">[0,1,2]</span></p> <p><strong>Explanation:</strong></p> <p><strong><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3149.Find%20the%20Minimum%20Cost%20Array%20Permutation/images/example0gif.gif" style="width: 235px; height: 235px;" /></strong></p> <p>The lexicographically smallest permutation with minimum cost is <code>[0,1,2]</code>. The cost of this permutation is <code>|0 - 0| + |1 - 2| + |2 - 1| = 2</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [0,2,1]</span></p> <p><strong>Output:</strong> <span class="example-io">[0,2,1]</span></p> <p><strong>Explanation:</strong></p> <p><strong><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3149.Find%20the%20Minimum%20Cost%20Array%20Permutation/images/example1gif.gif" style="width: 235px; height: 235px;" /></strong></p> <p>The lexicographically smallest permutation with minimum cost is <code>[0,2,1]</code>. The cost of this permutation is <code>|0 - 1| + |2 - 2| + |1 - 0| = 2</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= n == nums.length &lt;= 14</code></li> <li><code>nums</code> is a permutation of <code>[0, 1, 2, ..., n - 1]</code>.</li> </ul>
Bit Manipulation; Array; Dynamic Programming; Bitmask
Java
class Solution { private Integer[][] f; private int[] nums; private int[] ans; private int n; public int[] findPermutation(int[] nums) { n = nums.length; ans = new int[n]; this.nums = nums; f = new Integer[1 << n][n]; g(1, 0, 0); return ans; } private int dfs(int mask, int pre) { if (mask == (1 << n) - 1) { return Math.abs(pre - nums[0]); } if (f[mask][pre] != null) { return f[mask][pre]; } int res = Integer.MAX_VALUE; for (int cur = 1; cur < n; ++cur) { if ((mask >> cur & 1) == 0) { res = Math.min(res, Math.abs(pre - nums[cur]) + dfs(mask | 1 << cur, cur)); } } return f[mask][pre] = res; } private void g(int mask, int pre, int k) { ans[k] = pre; if (mask == (1 << n) - 1) { return; } int res = dfs(mask, pre); for (int cur = 1; cur < n; ++cur) { if ((mask >> cur & 1) == 0) { if (Math.abs(pre - nums[cur]) + dfs(mask | 1 << cur, cur) == res) { g(mask | 1 << cur, cur, k + 1); break; } } } } }
3,149
Find the Minimum Cost Array Permutation
Hard
<p>You are given an array <code>nums</code> which is a <span data-keyword="permutation">permutation</span> of <code>[0, 1, 2, ..., n - 1]</code>. The <strong>score</strong> of any permutation of <code>[0, 1, 2, ..., n - 1]</code> named <code>perm</code> is defined as:</p> <p><code>score(perm) = |perm[0] - nums[perm[1]]| + |perm[1] - nums[perm[2]]| + ... + |perm[n - 1] - nums[perm[0]]|</code></p> <p>Return the permutation <code>perm</code> which has the <strong>minimum</strong> possible score. If <em>multiple</em> permutations exist with this score, return the one that is <span data-keyword="lexicographically-smaller-array">lexicographically smallest</span> among them.</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 = [1,0,2]</span></p> <p><strong>Output:</strong> <span class="example-io">[0,1,2]</span></p> <p><strong>Explanation:</strong></p> <p><strong><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3149.Find%20the%20Minimum%20Cost%20Array%20Permutation/images/example0gif.gif" style="width: 235px; height: 235px;" /></strong></p> <p>The lexicographically smallest permutation with minimum cost is <code>[0,1,2]</code>. The cost of this permutation is <code>|0 - 0| + |1 - 2| + |2 - 1| = 2</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [0,2,1]</span></p> <p><strong>Output:</strong> <span class="example-io">[0,2,1]</span></p> <p><strong>Explanation:</strong></p> <p><strong><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3149.Find%20the%20Minimum%20Cost%20Array%20Permutation/images/example1gif.gif" style="width: 235px; height: 235px;" /></strong></p> <p>The lexicographically smallest permutation with minimum cost is <code>[0,2,1]</code>. The cost of this permutation is <code>|0 - 1| + |2 - 2| + |1 - 0| = 2</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= n == nums.length &lt;= 14</code></li> <li><code>nums</code> is a permutation of <code>[0, 1, 2, ..., n - 1]</code>.</li> </ul>
Bit Manipulation; Array; Dynamic Programming; Bitmask
Python
class Solution: def findPermutation(self, nums: List[int]) -> List[int]: @cache def dfs(mask: int, pre: int) -> int: if mask == (1 << n) - 1: return abs(pre - nums[0]) res = inf for cur in range(1, n): if mask >> cur & 1 ^ 1: res = min(res, abs(pre - nums[cur]) + dfs(mask | 1 << cur, cur)) return res def g(mask: int, pre: int): ans.append(pre) if mask == (1 << n) - 1: return res = dfs(mask, pre) for cur in range(1, n): if mask >> cur & 1 ^ 1: if abs(pre - nums[cur]) + dfs(mask | 1 << cur, cur) == res: g(mask | 1 << cur, cur) break n = len(nums) ans = [] g(1, 0) return ans
3,149
Find the Minimum Cost Array Permutation
Hard
<p>You are given an array <code>nums</code> which is a <span data-keyword="permutation">permutation</span> of <code>[0, 1, 2, ..., n - 1]</code>. The <strong>score</strong> of any permutation of <code>[0, 1, 2, ..., n - 1]</code> named <code>perm</code> is defined as:</p> <p><code>score(perm) = |perm[0] - nums[perm[1]]| + |perm[1] - nums[perm[2]]| + ... + |perm[n - 1] - nums[perm[0]]|</code></p> <p>Return the permutation <code>perm</code> which has the <strong>minimum</strong> possible score. If <em>multiple</em> permutations exist with this score, return the one that is <span data-keyword="lexicographically-smaller-array">lexicographically smallest</span> among them.</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 = [1,0,2]</span></p> <p><strong>Output:</strong> <span class="example-io">[0,1,2]</span></p> <p><strong>Explanation:</strong></p> <p><strong><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3149.Find%20the%20Minimum%20Cost%20Array%20Permutation/images/example0gif.gif" style="width: 235px; height: 235px;" /></strong></p> <p>The lexicographically smallest permutation with minimum cost is <code>[0,1,2]</code>. The cost of this permutation is <code>|0 - 0| + |1 - 2| + |2 - 1| = 2</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [0,2,1]</span></p> <p><strong>Output:</strong> <span class="example-io">[0,2,1]</span></p> <p><strong>Explanation:</strong></p> <p><strong><img alt="" src="https://fastly.jsdelivr.net/gh/doocs/leetcode@main/solution/3100-3199/3149.Find%20the%20Minimum%20Cost%20Array%20Permutation/images/example1gif.gif" style="width: 235px; height: 235px;" /></strong></p> <p>The lexicographically smallest permutation with minimum cost is <code>[0,2,1]</code>. The cost of this permutation is <code>|0 - 1| + |2 - 2| + |1 - 0| = 2</code>.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= n == nums.length &lt;= 14</code></li> <li><code>nums</code> is a permutation of <code>[0, 1, 2, ..., n - 1]</code>.</li> </ul>
Bit Manipulation; Array; Dynamic Programming; Bitmask
TypeScript
function findPermutation(nums: number[]): number[] { const n = nums.length; const ans: number[] = []; const f: number[][] = Array.from({ length: 1 << n }, () => Array(n).fill(-1)); const dfs = (mask: number, pre: number): number => { if (mask === (1 << n) - 1) { return Math.abs(pre - nums[0]); } if (f[mask][pre] !== -1) { return f[mask][pre]; } let res = Infinity; for (let cur = 1; cur < n; ++cur) { if (((mask >> cur) & 1) ^ 1) { res = Math.min(res, Math.abs(pre - nums[cur]) + dfs(mask | (1 << cur), cur)); } } return (f[mask][pre] = res); }; const g = (mask: number, pre: number) => { ans.push(pre); if (mask === (1 << n) - 1) { return; } const res = dfs(mask, pre); for (let cur = 1; cur < n; ++cur) { if (((mask >> cur) & 1) ^ 1) { if (Math.abs(pre - nums[cur]) + dfs(mask | (1 << cur), cur) === res) { g(mask | (1 << cur), cur); break; } } } }; g(1, 0); return ans; }
3,150
Invalid Tweets II
Easy
<p>Table: <code>Tweets</code></p> <pre> +----------------+---------+ | Column Name | Type | +----------------+---------+ | tweet_id | int | | content | varchar | +----------------+---------+ tweet_id is the primary key (column with unique values) for this table. This table contains all the tweets in a social media app. </pre> <p>Write a solution to find <strong>invalid tweets</strong>. A tweet is considered invalid if it meets <strong>any</strong> of the following criteria:</p> <ul> <li>It exceeds <code>140</code> characters in length.</li> <li>It has more than <code>3</code> mentions.</li> <li>It includes more than <code><font face="monospace">3</font></code>&nbsp;hashtags.</li> </ul> <p>Return <em>the result table ordered by</em> <code>tweet_id</code> <em>in <strong>ascending</strong> order</em>.</p> <p>The result format is in the following example.</p> <p>&nbsp;</p> <p><strong>Example:</strong></p> <div class="example-block"> <p><strong>Input:</strong></p> <p>Tweets table:</p> <pre class="example-io"> +----------+-----------------------------------------------------------------------------------+ | tweet_id | content | +----------+-----------------------------------------------------------------------------------+ | 1 | Traveling, exploring, and living my best life @JaneSmith @SaraJohnson @LisaTaylor | | | @MikeBrown #Foodie #Fitness #Learning | | 2 | Just had the best dinner with friends! #Foodie #Friends #Fun | | 4 | Working hard on my new project #Work #Goals #Productivity #Fun | +----------+-----------------------------------------------------------------------------------+ </pre> <p><strong>Output:</strong></p> <pre class="example-io"> +----------+ | tweet_id | +----------+ | 1 | | 4 | +----------+ </pre> <p><strong>Explanation:</strong></p> <ul> <li>tweet_id&nbsp;1 contains 4&nbsp;mentions.</li> <li>tweet_id 4 contains 4 hashtags.</li> </ul> Output table is ordered by tweet_id in ascending order.</div>
Database
Python
import pandas as pd def find_invalid_tweets(tweets: pd.DataFrame) -> pd.DataFrame: invalid_tweets = tweets[ (tweets["content"].str.len() > 140) | (tweets["content"].str.count("@") > 3) | (tweets["content"].str.count("#") > 3) ].sort_values(by="tweet_id") return invalid_tweets[["tweet_id"]]
3,150
Invalid Tweets II
Easy
<p>Table: <code>Tweets</code></p> <pre> +----------------+---------+ | Column Name | Type | +----------------+---------+ | tweet_id | int | | content | varchar | +----------------+---------+ tweet_id is the primary key (column with unique values) for this table. This table contains all the tweets in a social media app. </pre> <p>Write a solution to find <strong>invalid tweets</strong>. A tweet is considered invalid if it meets <strong>any</strong> of the following criteria:</p> <ul> <li>It exceeds <code>140</code> characters in length.</li> <li>It has more than <code>3</code> mentions.</li> <li>It includes more than <code><font face="monospace">3</font></code>&nbsp;hashtags.</li> </ul> <p>Return <em>the result table ordered by</em> <code>tweet_id</code> <em>in <strong>ascending</strong> order</em>.</p> <p>The result format is in the following example.</p> <p>&nbsp;</p> <p><strong>Example:</strong></p> <div class="example-block"> <p><strong>Input:</strong></p> <p>Tweets table:</p> <pre class="example-io"> +----------+-----------------------------------------------------------------------------------+ | tweet_id | content | +----------+-----------------------------------------------------------------------------------+ | 1 | Traveling, exploring, and living my best life @JaneSmith @SaraJohnson @LisaTaylor | | | @MikeBrown #Foodie #Fitness #Learning | | 2 | Just had the best dinner with friends! #Foodie #Friends #Fun | | 4 | Working hard on my new project #Work #Goals #Productivity #Fun | +----------+-----------------------------------------------------------------------------------+ </pre> <p><strong>Output:</strong></p> <pre class="example-io"> +----------+ | tweet_id | +----------+ | 1 | | 4 | +----------+ </pre> <p><strong>Explanation:</strong></p> <ul> <li>tweet_id&nbsp;1 contains 4&nbsp;mentions.</li> <li>tweet_id 4 contains 4 hashtags.</li> </ul> Output table is ordered by tweet_id in ascending order.</div>
Database
SQL
# Write your MySQL query statement below SELECT tweet_id FROM Tweets WHERE LENGTH(content) > 140 OR (LENGTH(content) - LENGTH(REPLACE(content, '@', ''))) > 3 OR (LENGTH(content) - LENGTH(REPLACE(content, '#', ''))) > 3 ORDER BY 1;
3,151
Special Array I
Easy
<p>An array is considered <strong>special</strong> if the <em>parity</em> of every pair of adjacent elements is different. In other words, one element in each pair <strong>must</strong> be even, and the other <strong>must</strong> be odd.</p> <p>You are given an array of integers <code>nums</code>. Return <code>true</code> if <code>nums</code> is a <strong>special</strong> array, otherwise, return <code>false</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]</span></p> <p><strong>Output:</strong> <span class="example-io">true</span></p> <p><strong>Explanation:</strong></p> <p>There is only one element. So the answer is <code>true</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,1,4]</span></p> <p><strong>Output:</strong> <span class="example-io">true</span></p> <p><strong>Explanation:</strong></p> <p>There is only two pairs: <code>(2,1)</code> and <code>(1,4)</code>, and both of them contain numbers with different parity. So the answer is <code>true</code>.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [4,3,1,6]</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p><code>nums[1]</code> and <code>nums[2]</code> are both odd. So the answer is <code>false</code>.</p> </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> </ul>
Array
C++
class Solution { public: bool isArraySpecial(vector<int>& nums) { for (int i = 1; i < nums.size(); ++i) { if (nums[i] % 2 == nums[i - 1] % 2) { return false; } } return true; } };
3,151
Special Array I
Easy
<p>An array is considered <strong>special</strong> if the <em>parity</em> of every pair of adjacent elements is different. In other words, one element in each pair <strong>must</strong> be even, and the other <strong>must</strong> be odd.</p> <p>You are given an array of integers <code>nums</code>. Return <code>true</code> if <code>nums</code> is a <strong>special</strong> array, otherwise, return <code>false</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]</span></p> <p><strong>Output:</strong> <span class="example-io">true</span></p> <p><strong>Explanation:</strong></p> <p>There is only one element. So the answer is <code>true</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,1,4]</span></p> <p><strong>Output:</strong> <span class="example-io">true</span></p> <p><strong>Explanation:</strong></p> <p>There is only two pairs: <code>(2,1)</code> and <code>(1,4)</code>, and both of them contain numbers with different parity. So the answer is <code>true</code>.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [4,3,1,6]</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p><code>nums[1]</code> and <code>nums[2]</code> are both odd. So the answer is <code>false</code>.</p> </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> </ul>
Array
Go
func isArraySpecial(nums []int) bool { for i, x := range nums[1:] { if x%2 == nums[i]%2 { return false } } return true }
3,151
Special Array I
Easy
<p>An array is considered <strong>special</strong> if the <em>parity</em> of every pair of adjacent elements is different. In other words, one element in each pair <strong>must</strong> be even, and the other <strong>must</strong> be odd.</p> <p>You are given an array of integers <code>nums</code>. Return <code>true</code> if <code>nums</code> is a <strong>special</strong> array, otherwise, return <code>false</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]</span></p> <p><strong>Output:</strong> <span class="example-io">true</span></p> <p><strong>Explanation:</strong></p> <p>There is only one element. So the answer is <code>true</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,1,4]</span></p> <p><strong>Output:</strong> <span class="example-io">true</span></p> <p><strong>Explanation:</strong></p> <p>There is only two pairs: <code>(2,1)</code> and <code>(1,4)</code>, and both of them contain numbers with different parity. So the answer is <code>true</code>.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [4,3,1,6]</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p><code>nums[1]</code> and <code>nums[2]</code> are both odd. So the answer is <code>false</code>.</p> </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> </ul>
Array
Java
class Solution { public boolean isArraySpecial(int[] nums) { for (int i = 1; i < nums.length; ++i) { if (nums[i] % 2 == nums[i - 1] % 2) { return false; } } return true; } }
3,151
Special Array I
Easy
<p>An array is considered <strong>special</strong> if the <em>parity</em> of every pair of adjacent elements is different. In other words, one element in each pair <strong>must</strong> be even, and the other <strong>must</strong> be odd.</p> <p>You are given an array of integers <code>nums</code>. Return <code>true</code> if <code>nums</code> is a <strong>special</strong> array, otherwise, return <code>false</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]</span></p> <p><strong>Output:</strong> <span class="example-io">true</span></p> <p><strong>Explanation:</strong></p> <p>There is only one element. So the answer is <code>true</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,1,4]</span></p> <p><strong>Output:</strong> <span class="example-io">true</span></p> <p><strong>Explanation:</strong></p> <p>There is only two pairs: <code>(2,1)</code> and <code>(1,4)</code>, and both of them contain numbers with different parity. So the answer is <code>true</code>.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [4,3,1,6]</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p><code>nums[1]</code> and <code>nums[2]</code> are both odd. So the answer is <code>false</code>.</p> </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> </ul>
Array
Python
class Solution: def isArraySpecial(self, nums: List[int]) -> bool: return all(a % 2 != b % 2 for a, b in pairwise(nums))
3,151
Special Array I
Easy
<p>An array is considered <strong>special</strong> if the <em>parity</em> of every pair of adjacent elements is different. In other words, one element in each pair <strong>must</strong> be even, and the other <strong>must</strong> be odd.</p> <p>You are given an array of integers <code>nums</code>. Return <code>true</code> if <code>nums</code> is a <strong>special</strong> array, otherwise, return <code>false</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]</span></p> <p><strong>Output:</strong> <span class="example-io">true</span></p> <p><strong>Explanation:</strong></p> <p>There is only one element. So the answer is <code>true</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [2,1,4]</span></p> <p><strong>Output:</strong> <span class="example-io">true</span></p> <p><strong>Explanation:</strong></p> <p>There is only two pairs: <code>(2,1)</code> and <code>(1,4)</code>, and both of them contain numbers with different parity. So the answer is <code>true</code>.</p> </div> <p><strong class="example">Example 3:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [4,3,1,6]</span></p> <p><strong>Output:</strong> <span class="example-io">false</span></p> <p><strong>Explanation:</strong></p> <p><code>nums[1]</code> and <code>nums[2]</code> are both odd. So the answer is <code>false</code>.</p> </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> </ul>
Array
TypeScript
function isArraySpecial(nums: number[]): boolean { for (let i = 1; i < nums.length; ++i) { if (nums[i] % 2 === nums[i - 1] % 2) { return false; } } return true; }
3,152
Special Array II
Medium
<p>An array is considered <strong>special</strong> if every pair of its adjacent elements contains two numbers with different parity.</p> <p>You are given an array of integer <code>nums</code> and a 2D integer matrix <code>queries</code>, where for <code>queries[i] = [from<sub>i</sub>, to<sub>i</sub>]</code> your task is to check that <span data-keyword="subarray">subarray</span> <code>nums[from<sub>i</sub>..to<sub>i</sub>]</code> is <strong>special</strong> or not.</p> <p>Return an array of booleans <code>answer</code> such that <code>answer[i]</code> is <code>true</code> if <code>nums[from<sub>i</sub>..to<sub>i</sub>]</code> is special.<!-- notionvc: e5d6f4e2-d20a-4fbd-9c7f-22fbe52ef730 --></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 = [3,4,1,2,6], queries = [[0,4]]</span></p> <p><strong>Output:</strong> <span class="example-io">[false]</span></p> <p><strong>Explanation:</strong></p> <p>The subarray is <code>[3,4,1,2,6]</code>. 2 and 6 are both even.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [4,3,1,6], queries = [[0,2],[2,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">[false,true]</span></p> <p><strong>Explanation:</strong></p> <ol> <li>The subarray is <code>[4,3,1]</code>. 3 and 1 are both odd. So the answer to this query is <code>false</code>.</li> <li>The subarray is <code>[1,6]</code>. There is only one pair: <code>(1,6)</code> and it contains numbers with different parity. So the answer to this query is <code>true</code>.</li> </ol> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= queries.length &lt;= 10<sup>5</sup></code></li> <li><code>queries[i].length == 2</code></li> <li><code>0 &lt;= queries[i][0] &lt;= queries[i][1] &lt;= nums.length - 1</code></li> </ul>
Array; Binary Search; Prefix Sum
C++
class Solution { public: vector<bool> isArraySpecial(vector<int>& nums, vector<vector<int>>& queries) { int n = nums.size(); vector<int> d(n); iota(d.begin(), d.end(), 0); for (int i = 1; i < n; ++i) { if (nums[i] % 2 != nums[i - 1] % 2) { d[i] = d[i - 1]; } } vector<bool> ans; for (auto& q : queries) { ans.push_back(d[q[1]] <= q[0]); } return ans; } };
3,152
Special Array II
Medium
<p>An array is considered <strong>special</strong> if every pair of its adjacent elements contains two numbers with different parity.</p> <p>You are given an array of integer <code>nums</code> and a 2D integer matrix <code>queries</code>, where for <code>queries[i] = [from<sub>i</sub>, to<sub>i</sub>]</code> your task is to check that <span data-keyword="subarray">subarray</span> <code>nums[from<sub>i</sub>..to<sub>i</sub>]</code> is <strong>special</strong> or not.</p> <p>Return an array of booleans <code>answer</code> such that <code>answer[i]</code> is <code>true</code> if <code>nums[from<sub>i</sub>..to<sub>i</sub>]</code> is special.<!-- notionvc: e5d6f4e2-d20a-4fbd-9c7f-22fbe52ef730 --></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 = [3,4,1,2,6], queries = [[0,4]]</span></p> <p><strong>Output:</strong> <span class="example-io">[false]</span></p> <p><strong>Explanation:</strong></p> <p>The subarray is <code>[3,4,1,2,6]</code>. 2 and 6 are both even.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [4,3,1,6], queries = [[0,2],[2,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">[false,true]</span></p> <p><strong>Explanation:</strong></p> <ol> <li>The subarray is <code>[4,3,1]</code>. 3 and 1 are both odd. So the answer to this query is <code>false</code>.</li> <li>The subarray is <code>[1,6]</code>. There is only one pair: <code>(1,6)</code> and it contains numbers with different parity. So the answer to this query is <code>true</code>.</li> </ol> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= queries.length &lt;= 10<sup>5</sup></code></li> <li><code>queries[i].length == 2</code></li> <li><code>0 &lt;= queries[i][0] &lt;= queries[i][1] &lt;= nums.length - 1</code></li> </ul>
Array; Binary Search; Prefix Sum
Go
func isArraySpecial(nums []int, queries [][]int) (ans []bool) { n := len(nums) d := make([]int, n) for i := range d { d[i] = i } for i := 1; i < len(nums); i++ { if nums[i]%2 != nums[i-1]%2 { d[i] = d[i-1] } } for _, q := range queries { ans = append(ans, d[q[1]] <= q[0]) } return }
3,152
Special Array II
Medium
<p>An array is considered <strong>special</strong> if every pair of its adjacent elements contains two numbers with different parity.</p> <p>You are given an array of integer <code>nums</code> and a 2D integer matrix <code>queries</code>, where for <code>queries[i] = [from<sub>i</sub>, to<sub>i</sub>]</code> your task is to check that <span data-keyword="subarray">subarray</span> <code>nums[from<sub>i</sub>..to<sub>i</sub>]</code> is <strong>special</strong> or not.</p> <p>Return an array of booleans <code>answer</code> such that <code>answer[i]</code> is <code>true</code> if <code>nums[from<sub>i</sub>..to<sub>i</sub>]</code> is special.<!-- notionvc: e5d6f4e2-d20a-4fbd-9c7f-22fbe52ef730 --></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 = [3,4,1,2,6], queries = [[0,4]]</span></p> <p><strong>Output:</strong> <span class="example-io">[false]</span></p> <p><strong>Explanation:</strong></p> <p>The subarray is <code>[3,4,1,2,6]</code>. 2 and 6 are both even.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [4,3,1,6], queries = [[0,2],[2,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">[false,true]</span></p> <p><strong>Explanation:</strong></p> <ol> <li>The subarray is <code>[4,3,1]</code>. 3 and 1 are both odd. So the answer to this query is <code>false</code>.</li> <li>The subarray is <code>[1,6]</code>. There is only one pair: <code>(1,6)</code> and it contains numbers with different parity. So the answer to this query is <code>true</code>.</li> </ol> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= queries.length &lt;= 10<sup>5</sup></code></li> <li><code>queries[i].length == 2</code></li> <li><code>0 &lt;= queries[i][0] &lt;= queries[i][1] &lt;= nums.length - 1</code></li> </ul>
Array; Binary Search; Prefix Sum
Java
class Solution { public boolean[] isArraySpecial(int[] nums, int[][] queries) { int n = nums.length; int[] d = new int[n]; for (int i = 1; i < n; ++i) { if (nums[i] % 2 != nums[i - 1] % 2) { d[i] = d[i - 1]; } else { d[i] = i; } } int m = queries.length; boolean[] ans = new boolean[m]; for (int i = 0; i < m; ++i) { ans[i] = d[queries[i][1]] <= queries[i][0]; } return ans; } }
3,152
Special Array II
Medium
<p>An array is considered <strong>special</strong> if every pair of its adjacent elements contains two numbers with different parity.</p> <p>You are given an array of integer <code>nums</code> and a 2D integer matrix <code>queries</code>, where for <code>queries[i] = [from<sub>i</sub>, to<sub>i</sub>]</code> your task is to check that <span data-keyword="subarray">subarray</span> <code>nums[from<sub>i</sub>..to<sub>i</sub>]</code> is <strong>special</strong> or not.</p> <p>Return an array of booleans <code>answer</code> such that <code>answer[i]</code> is <code>true</code> if <code>nums[from<sub>i</sub>..to<sub>i</sub>]</code> is special.<!-- notionvc: e5d6f4e2-d20a-4fbd-9c7f-22fbe52ef730 --></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 = [3,4,1,2,6], queries = [[0,4]]</span></p> <p><strong>Output:</strong> <span class="example-io">[false]</span></p> <p><strong>Explanation:</strong></p> <p>The subarray is <code>[3,4,1,2,6]</code>. 2 and 6 are both even.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [4,3,1,6], queries = [[0,2],[2,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">[false,true]</span></p> <p><strong>Explanation:</strong></p> <ol> <li>The subarray is <code>[4,3,1]</code>. 3 and 1 are both odd. So the answer to this query is <code>false</code>.</li> <li>The subarray is <code>[1,6]</code>. There is only one pair: <code>(1,6)</code> and it contains numbers with different parity. So the answer to this query is <code>true</code>.</li> </ol> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= queries.length &lt;= 10<sup>5</sup></code></li> <li><code>queries[i].length == 2</code></li> <li><code>0 &lt;= queries[i][0] &lt;= queries[i][1] &lt;= nums.length - 1</code></li> </ul>
Array; Binary Search; Prefix Sum
Python
class Solution: def isArraySpecial(self, nums: List[int], queries: List[List[int]]) -> List[bool]: n = len(nums) d = list(range(n)) for i in range(1, n): if nums[i] % 2 != nums[i - 1] % 2: d[i] = d[i - 1] return [d[t] <= f for f, t in queries]
3,152
Special Array II
Medium
<p>An array is considered <strong>special</strong> if every pair of its adjacent elements contains two numbers with different parity.</p> <p>You are given an array of integer <code>nums</code> and a 2D integer matrix <code>queries</code>, where for <code>queries[i] = [from<sub>i</sub>, to<sub>i</sub>]</code> your task is to check that <span data-keyword="subarray">subarray</span> <code>nums[from<sub>i</sub>..to<sub>i</sub>]</code> is <strong>special</strong> or not.</p> <p>Return an array of booleans <code>answer</code> such that <code>answer[i]</code> is <code>true</code> if <code>nums[from<sub>i</sub>..to<sub>i</sub>]</code> is special.<!-- notionvc: e5d6f4e2-d20a-4fbd-9c7f-22fbe52ef730 --></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 = [3,4,1,2,6], queries = [[0,4]]</span></p> <p><strong>Output:</strong> <span class="example-io">[false]</span></p> <p><strong>Explanation:</strong></p> <p>The subarray is <code>[3,4,1,2,6]</code>. 2 and 6 are both even.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [4,3,1,6], queries = [[0,2],[2,3]]</span></p> <p><strong>Output:</strong> <span class="example-io">[false,true]</span></p> <p><strong>Explanation:</strong></p> <ol> <li>The subarray is <code>[4,3,1]</code>. 3 and 1 are both odd. So the answer to this query is <code>false</code>.</li> <li>The subarray is <code>[1,6]</code>. There is only one pair: <code>(1,6)</code> and it contains numbers with different parity. So the answer to this query is <code>true</code>.</li> </ol> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>1 &lt;= nums.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= queries.length &lt;= 10<sup>5</sup></code></li> <li><code>queries[i].length == 2</code></li> <li><code>0 &lt;= queries[i][0] &lt;= queries[i][1] &lt;= nums.length - 1</code></li> </ul>
Array; Binary Search; Prefix Sum
TypeScript
function isArraySpecial(nums: number[], queries: number[][]): boolean[] { const n = nums.length; const d: number[] = Array.from({ length: n }, (_, i) => i); for (let i = 1; i < n; ++i) { if (nums[i] % 2 !== nums[i - 1] % 2) { d[i] = d[i - 1]; } } return queries.map(([from, to]) => d[to] <= from); }
3,153
Sum of Digit Differences of All Pairs
Medium
<p>You are given an array <code>nums</code> consisting of <strong>positive</strong> integers where all integers have the <strong>same</strong> number of digits.</p> <p>The <strong>digit difference</strong> between two integers is the <em>count</em> of different digits that are in the <strong>same</strong> position in the two integers.</p> <p>Return the <strong>sum</strong> of the <strong>digit differences</strong> between <strong>all</strong> pairs of integers in <code>nums</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 = [13,23,12]</span></p> <p><strong>Output:</strong> 4</p> <p><strong>Explanation:</strong><br /> We have the following:<br /> - The digit difference between <strong>1</strong>3 and <strong>2</strong>3 is 1.<br /> - The digit difference between 1<strong>3</strong> and 1<strong>2</strong> is 1.<br /> - The digit difference between <strong>23</strong> and <strong>12</strong> is 2.<br /> So the total sum of digit differences between all pairs of integers is <code>1 + 1 + 2 = 4</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [10,10,10,10]</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong><br /> All the integers in the array are the same. So the total sum of digit differences between all pairs of integers will be 0.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= nums.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt; 10<sup>9</sup></code></li> <li>All integers in <code>nums</code> have the same number of digits.</li> </ul>
Array; Hash Table; Math; Counting
C++
class Solution { public: long long sumDigitDifferences(vector<int>& nums) { int n = nums.size(); int m = floor(log10(nums[0])) + 1; int cnt[10]; long long ans = 0; for (int k = 0; k < m; ++k) { memset(cnt, 0, sizeof(cnt)); for (int i = 0; i < n; ++i) { ++cnt[nums[i] % 10]; nums[i] /= 10; } for (int i = 0; i < 10; ++i) { ans += 1LL * cnt[i] * (n - cnt[i]); } } return ans / 2; } };
3,153
Sum of Digit Differences of All Pairs
Medium
<p>You are given an array <code>nums</code> consisting of <strong>positive</strong> integers where all integers have the <strong>same</strong> number of digits.</p> <p>The <strong>digit difference</strong> between two integers is the <em>count</em> of different digits that are in the <strong>same</strong> position in the two integers.</p> <p>Return the <strong>sum</strong> of the <strong>digit differences</strong> between <strong>all</strong> pairs of integers in <code>nums</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 = [13,23,12]</span></p> <p><strong>Output:</strong> 4</p> <p><strong>Explanation:</strong><br /> We have the following:<br /> - The digit difference between <strong>1</strong>3 and <strong>2</strong>3 is 1.<br /> - The digit difference between 1<strong>3</strong> and 1<strong>2</strong> is 1.<br /> - The digit difference between <strong>23</strong> and <strong>12</strong> is 2.<br /> So the total sum of digit differences between all pairs of integers is <code>1 + 1 + 2 = 4</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [10,10,10,10]</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong><br /> All the integers in the array are the same. So the total sum of digit differences between all pairs of integers will be 0.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= nums.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt; 10<sup>9</sup></code></li> <li>All integers in <code>nums</code> have the same number of digits.</li> </ul>
Array; Hash Table; Math; Counting
Go
func sumDigitDifferences(nums []int) (ans int64) { n := len(nums) m := int(math.Floor(math.Log10(float64(nums[0])))) + 1 for k := 0; k < m; k++ { cnt := [10]int{} for i, x := range nums { cnt[x%10]++ nums[i] /= 10 } for _, v := range cnt { ans += int64(v) * int64(n-v) } } ans /= 2 return }
3,153
Sum of Digit Differences of All Pairs
Medium
<p>You are given an array <code>nums</code> consisting of <strong>positive</strong> integers where all integers have the <strong>same</strong> number of digits.</p> <p>The <strong>digit difference</strong> between two integers is the <em>count</em> of different digits that are in the <strong>same</strong> position in the two integers.</p> <p>Return the <strong>sum</strong> of the <strong>digit differences</strong> between <strong>all</strong> pairs of integers in <code>nums</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 = [13,23,12]</span></p> <p><strong>Output:</strong> 4</p> <p><strong>Explanation:</strong><br /> We have the following:<br /> - The digit difference between <strong>1</strong>3 and <strong>2</strong>3 is 1.<br /> - The digit difference between 1<strong>3</strong> and 1<strong>2</strong> is 1.<br /> - The digit difference between <strong>23</strong> and <strong>12</strong> is 2.<br /> So the total sum of digit differences between all pairs of integers is <code>1 + 1 + 2 = 4</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [10,10,10,10]</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong><br /> All the integers in the array are the same. So the total sum of digit differences between all pairs of integers will be 0.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= nums.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt; 10<sup>9</sup></code></li> <li>All integers in <code>nums</code> have the same number of digits.</li> </ul>
Array; Hash Table; Math; Counting
Java
class Solution { public long sumDigitDifferences(int[] nums) { int n = nums.length; int m = (int) Math.floor(Math.log10(nums[0])) + 1; int[] cnt = new int[10]; long ans = 0; for (int k = 0; k < m; ++k) { Arrays.fill(cnt, 0); for (int i = 0; i < n; ++i) { ++cnt[nums[i] % 10]; nums[i] /= 10; } for (int i = 0; i < 10; ++i) { ans += 1L * cnt[i] * (n - cnt[i]); } } return ans / 2; } }
3,153
Sum of Digit Differences of All Pairs
Medium
<p>You are given an array <code>nums</code> consisting of <strong>positive</strong> integers where all integers have the <strong>same</strong> number of digits.</p> <p>The <strong>digit difference</strong> between two integers is the <em>count</em> of different digits that are in the <strong>same</strong> position in the two integers.</p> <p>Return the <strong>sum</strong> of the <strong>digit differences</strong> between <strong>all</strong> pairs of integers in <code>nums</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 = [13,23,12]</span></p> <p><strong>Output:</strong> 4</p> <p><strong>Explanation:</strong><br /> We have the following:<br /> - The digit difference between <strong>1</strong>3 and <strong>2</strong>3 is 1.<br /> - The digit difference between 1<strong>3</strong> and 1<strong>2</strong> is 1.<br /> - The digit difference between <strong>23</strong> and <strong>12</strong> is 2.<br /> So the total sum of digit differences between all pairs of integers is <code>1 + 1 + 2 = 4</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [10,10,10,10]</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong><br /> All the integers in the array are the same. So the total sum of digit differences between all pairs of integers will be 0.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= nums.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt; 10<sup>9</sup></code></li> <li>All integers in <code>nums</code> have the same number of digits.</li> </ul>
Array; Hash Table; Math; Counting
Python
class Solution: def sumDigitDifferences(self, nums: List[int]) -> int: n = len(nums) m = int(log10(nums[0])) + 1 ans = 0 for _ in range(m): cnt = Counter() for i, x in enumerate(nums): nums[i], y = divmod(x, 10) cnt[y] += 1 ans += sum(v * (n - v) for v in cnt.values()) // 2 return ans
3,153
Sum of Digit Differences of All Pairs
Medium
<p>You are given an array <code>nums</code> consisting of <strong>positive</strong> integers where all integers have the <strong>same</strong> number of digits.</p> <p>The <strong>digit difference</strong> between two integers is the <em>count</em> of different digits that are in the <strong>same</strong> position in the two integers.</p> <p>Return the <strong>sum</strong> of the <strong>digit differences</strong> between <strong>all</strong> pairs of integers in <code>nums</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 = [13,23,12]</span></p> <p><strong>Output:</strong> 4</p> <p><strong>Explanation:</strong><br /> We have the following:<br /> - The digit difference between <strong>1</strong>3 and <strong>2</strong>3 is 1.<br /> - The digit difference between 1<strong>3</strong> and 1<strong>2</strong> is 1.<br /> - The digit difference between <strong>23</strong> and <strong>12</strong> is 2.<br /> So the total sum of digit differences between all pairs of integers is <code>1 + 1 + 2 = 4</code>.</p> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">nums = [10,10,10,10]</span></p> <p><strong>Output:</strong> <span class="example-io">0</span></p> <p><strong>Explanation:</strong><br /> All the integers in the array are the same. So the total sum of digit differences between all pairs of integers will be 0.</p> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>2 &lt;= nums.length &lt;= 10<sup>5</sup></code></li> <li><code>1 &lt;= nums[i] &lt; 10<sup>9</sup></code></li> <li>All integers in <code>nums</code> have the same number of digits.</li> </ul>
Array; Hash Table; Math; Counting
TypeScript
function sumDigitDifferences(nums: number[]): number { const n = nums.length; const m = Math.floor(Math.log10(nums[0])) + 1; let ans: bigint = BigInt(0); for (let k = 0; k < m; ++k) { const cnt: number[] = Array(10).fill(0); for (let i = 0; i < n; ++i) { ++cnt[nums[i] % 10]; nums[i] = Math.floor(nums[i] / 10); } for (let i = 0; i < 10; ++i) { ans += BigInt(cnt[i]) * BigInt(n - cnt[i]); } } ans /= BigInt(2); return Number(ans); }
3,154
Find Number of Ways to Reach the K-th Stair
Hard
<p>You are given a <strong>non-negative</strong> integer <code>k</code>. There exists a staircase with an infinite number of stairs, with the <strong>lowest</strong> stair numbered 0.</p> <p>Alice has an integer <code>jump</code>, with an initial value of 0. She starts on stair 1 and wants to reach stair <code>k</code> using <strong>any</strong> number of <strong>operations</strong>. If she is on stair <code>i</code>, in one <strong>operation</strong> she can:</p> <ul> <li>Go down to stair <code>i - 1</code>. This operation <strong>cannot</strong> be used consecutively or on stair 0.</li> <li>Go up to stair <code>i + 2<sup>jump</sup></code>. And then, <code>jump</code> becomes <code>jump + 1</code>.</li> </ul> <p>Return the <em>total</em> number of ways Alice can reach stair <code>k</code>.</p> <p><strong>Note</strong> that it is possible that Alice reaches the stair <code>k</code>, and performs some operations to reach the stair <code>k</code> again.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">k = 0</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>The 2 possible ways of reaching stair 0 are:</p> <ul> <li>Alice starts at stair 1. <ul> <li>Using an operation of the first type, she goes down 1 stair to reach stair 0.</li> </ul> </li> <li>Alice starts at stair 1. <ul> <li>Using an operation of the first type, she goes down 1 stair to reach stair 0.</li> <li>Using an operation of the second type, she goes up 2<sup>0</sup> stairs to reach stair 1.</li> <li>Using an operation of the first type, she goes down 1 stair to reach stair 0.</li> </ul> </li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">k = 1</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <p>The 4 possible ways of reaching stair 1 are:</p> <ul> <li>Alice starts at stair 1. Alice is at stair 1.</li> <li>Alice starts at stair 1. <ul> <li>Using an operation of the first type, she goes down 1 stair to reach stair 0.</li> <li>Using an operation of the second type, she goes up 2<sup>0</sup> stairs to reach stair 1.</li> </ul> </li> <li>Alice starts at stair 1. <ul> <li>Using an operation of the second type, she goes up 2<sup>0</sup> stairs to reach stair 2.</li> <li>Using an operation of the first type, she goes down 1 stair to reach stair 1.</li> </ul> </li> <li>Alice starts at stair 1. <ul> <li>Using an operation of the first type, she goes down 1 stair to reach stair 0.</li> <li>Using an operation of the second type, she goes up 2<sup>0</sup> stairs to reach stair 1.</li> <li>Using an operation of the first type, she goes down 1 stair to reach stair 0.</li> <li>Using an operation of the second type, she goes up 2<sup>1</sup> stairs to reach stair 2.</li> <li>Using an operation of the first type, she goes down 1 stair to reach stair 1.</li> </ul> </li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>0 &lt;= k &lt;= 10<sup>9</sup></code></li> </ul>
Bit Manipulation; Memoization; Math; Dynamic Programming; Combinatorics
C++
class Solution { public: int waysToReachStair(int k) { unordered_map<long long, int> f; auto dfs = [&](this auto&& dfs, int i, int j, int jump) -> int { if (i > k + 1) { return 0; } long long key = ((long long) i << 32) | jump << 1 | j; if (f.contains(key)) { return f[key]; } int ans = i == k ? 1 : 0; if (i > 0 && j == 0) { ans += dfs(i - 1, 1, jump); } ans += dfs(i + (1 << jump), 0, jump + 1); f[key] = ans; return ans; }; return dfs(1, 0, 0); } };
3,154
Find Number of Ways to Reach the K-th Stair
Hard
<p>You are given a <strong>non-negative</strong> integer <code>k</code>. There exists a staircase with an infinite number of stairs, with the <strong>lowest</strong> stair numbered 0.</p> <p>Alice has an integer <code>jump</code>, with an initial value of 0. She starts on stair 1 and wants to reach stair <code>k</code> using <strong>any</strong> number of <strong>operations</strong>. If she is on stair <code>i</code>, in one <strong>operation</strong> she can:</p> <ul> <li>Go down to stair <code>i - 1</code>. This operation <strong>cannot</strong> be used consecutively or on stair 0.</li> <li>Go up to stair <code>i + 2<sup>jump</sup></code>. And then, <code>jump</code> becomes <code>jump + 1</code>.</li> </ul> <p>Return the <em>total</em> number of ways Alice can reach stair <code>k</code>.</p> <p><strong>Note</strong> that it is possible that Alice reaches the stair <code>k</code>, and performs some operations to reach the stair <code>k</code> again.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">k = 0</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>The 2 possible ways of reaching stair 0 are:</p> <ul> <li>Alice starts at stair 1. <ul> <li>Using an operation of the first type, she goes down 1 stair to reach stair 0.</li> </ul> </li> <li>Alice starts at stair 1. <ul> <li>Using an operation of the first type, she goes down 1 stair to reach stair 0.</li> <li>Using an operation of the second type, she goes up 2<sup>0</sup> stairs to reach stair 1.</li> <li>Using an operation of the first type, she goes down 1 stair to reach stair 0.</li> </ul> </li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">k = 1</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <p>The 4 possible ways of reaching stair 1 are:</p> <ul> <li>Alice starts at stair 1. Alice is at stair 1.</li> <li>Alice starts at stair 1. <ul> <li>Using an operation of the first type, she goes down 1 stair to reach stair 0.</li> <li>Using an operation of the second type, she goes up 2<sup>0</sup> stairs to reach stair 1.</li> </ul> </li> <li>Alice starts at stair 1. <ul> <li>Using an operation of the second type, she goes up 2<sup>0</sup> stairs to reach stair 2.</li> <li>Using an operation of the first type, she goes down 1 stair to reach stair 1.</li> </ul> </li> <li>Alice starts at stair 1. <ul> <li>Using an operation of the first type, she goes down 1 stair to reach stair 0.</li> <li>Using an operation of the second type, she goes up 2<sup>0</sup> stairs to reach stair 1.</li> <li>Using an operation of the first type, she goes down 1 stair to reach stair 0.</li> <li>Using an operation of the second type, she goes up 2<sup>1</sup> stairs to reach stair 2.</li> <li>Using an operation of the first type, she goes down 1 stair to reach stair 1.</li> </ul> </li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>0 &lt;= k &lt;= 10<sup>9</sup></code></li> </ul>
Bit Manipulation; Memoization; Math; Dynamic Programming; Combinatorics
Go
func waysToReachStair(k int) int { f := map[int]int{} var dfs func(i, j, jump int) int dfs = func(i, j, jump int) int { if i > k+1 { return 0 } key := (i << 32) | jump<<1 | j if v, has := f[key]; has { return v } ans := 0 if i == k { ans++ } if i > 0 && j == 0 { ans += dfs(i-1, 1, jump) } ans += dfs(i+(1<<jump), 0, jump+1) f[key] = ans return ans } return dfs(1, 0, 0) }
3,154
Find Number of Ways to Reach the K-th Stair
Hard
<p>You are given a <strong>non-negative</strong> integer <code>k</code>. There exists a staircase with an infinite number of stairs, with the <strong>lowest</strong> stair numbered 0.</p> <p>Alice has an integer <code>jump</code>, with an initial value of 0. She starts on stair 1 and wants to reach stair <code>k</code> using <strong>any</strong> number of <strong>operations</strong>. If she is on stair <code>i</code>, in one <strong>operation</strong> she can:</p> <ul> <li>Go down to stair <code>i - 1</code>. This operation <strong>cannot</strong> be used consecutively or on stair 0.</li> <li>Go up to stair <code>i + 2<sup>jump</sup></code>. And then, <code>jump</code> becomes <code>jump + 1</code>.</li> </ul> <p>Return the <em>total</em> number of ways Alice can reach stair <code>k</code>.</p> <p><strong>Note</strong> that it is possible that Alice reaches the stair <code>k</code>, and performs some operations to reach the stair <code>k</code> again.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">k = 0</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>The 2 possible ways of reaching stair 0 are:</p> <ul> <li>Alice starts at stair 1. <ul> <li>Using an operation of the first type, she goes down 1 stair to reach stair 0.</li> </ul> </li> <li>Alice starts at stair 1. <ul> <li>Using an operation of the first type, she goes down 1 stair to reach stair 0.</li> <li>Using an operation of the second type, she goes up 2<sup>0</sup> stairs to reach stair 1.</li> <li>Using an operation of the first type, she goes down 1 stair to reach stair 0.</li> </ul> </li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">k = 1</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <p>The 4 possible ways of reaching stair 1 are:</p> <ul> <li>Alice starts at stair 1. Alice is at stair 1.</li> <li>Alice starts at stair 1. <ul> <li>Using an operation of the first type, she goes down 1 stair to reach stair 0.</li> <li>Using an operation of the second type, she goes up 2<sup>0</sup> stairs to reach stair 1.</li> </ul> </li> <li>Alice starts at stair 1. <ul> <li>Using an operation of the second type, she goes up 2<sup>0</sup> stairs to reach stair 2.</li> <li>Using an operation of the first type, she goes down 1 stair to reach stair 1.</li> </ul> </li> <li>Alice starts at stair 1. <ul> <li>Using an operation of the first type, she goes down 1 stair to reach stair 0.</li> <li>Using an operation of the second type, she goes up 2<sup>0</sup> stairs to reach stair 1.</li> <li>Using an operation of the first type, she goes down 1 stair to reach stair 0.</li> <li>Using an operation of the second type, she goes up 2<sup>1</sup> stairs to reach stair 2.</li> <li>Using an operation of the first type, she goes down 1 stair to reach stair 1.</li> </ul> </li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>0 &lt;= k &lt;= 10<sup>9</sup></code></li> </ul>
Bit Manipulation; Memoization; Math; Dynamic Programming; Combinatorics
Java
class Solution { private Map<Long, Integer> f = new HashMap<>(); private int k; public int waysToReachStair(int k) { this.k = k; return dfs(1, 0, 0); } private int dfs(int i, int j, int jump) { if (i > k + 1) { return 0; } long key = ((long) i << 32) | jump << 1 | j; if (f.containsKey(key)) { return f.get(key); } int ans = i == k ? 1 : 0; if (i > 0 && j == 0) { ans += dfs(i - 1, 1, jump); } ans += dfs(i + (1 << jump), 0, jump + 1); f.put(key, ans); return ans; } }
3,154
Find Number of Ways to Reach the K-th Stair
Hard
<p>You are given a <strong>non-negative</strong> integer <code>k</code>. There exists a staircase with an infinite number of stairs, with the <strong>lowest</strong> stair numbered 0.</p> <p>Alice has an integer <code>jump</code>, with an initial value of 0. She starts on stair 1 and wants to reach stair <code>k</code> using <strong>any</strong> number of <strong>operations</strong>. If she is on stair <code>i</code>, in one <strong>operation</strong> she can:</p> <ul> <li>Go down to stair <code>i - 1</code>. This operation <strong>cannot</strong> be used consecutively or on stair 0.</li> <li>Go up to stair <code>i + 2<sup>jump</sup></code>. And then, <code>jump</code> becomes <code>jump + 1</code>.</li> </ul> <p>Return the <em>total</em> number of ways Alice can reach stair <code>k</code>.</p> <p><strong>Note</strong> that it is possible that Alice reaches the stair <code>k</code>, and performs some operations to reach the stair <code>k</code> again.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">k = 0</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>The 2 possible ways of reaching stair 0 are:</p> <ul> <li>Alice starts at stair 1. <ul> <li>Using an operation of the first type, she goes down 1 stair to reach stair 0.</li> </ul> </li> <li>Alice starts at stair 1. <ul> <li>Using an operation of the first type, she goes down 1 stair to reach stair 0.</li> <li>Using an operation of the second type, she goes up 2<sup>0</sup> stairs to reach stair 1.</li> <li>Using an operation of the first type, she goes down 1 stair to reach stair 0.</li> </ul> </li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">k = 1</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <p>The 4 possible ways of reaching stair 1 are:</p> <ul> <li>Alice starts at stair 1. Alice is at stair 1.</li> <li>Alice starts at stair 1. <ul> <li>Using an operation of the first type, she goes down 1 stair to reach stair 0.</li> <li>Using an operation of the second type, she goes up 2<sup>0</sup> stairs to reach stair 1.</li> </ul> </li> <li>Alice starts at stair 1. <ul> <li>Using an operation of the second type, she goes up 2<sup>0</sup> stairs to reach stair 2.</li> <li>Using an operation of the first type, she goes down 1 stair to reach stair 1.</li> </ul> </li> <li>Alice starts at stair 1. <ul> <li>Using an operation of the first type, she goes down 1 stair to reach stair 0.</li> <li>Using an operation of the second type, she goes up 2<sup>0</sup> stairs to reach stair 1.</li> <li>Using an operation of the first type, she goes down 1 stair to reach stair 0.</li> <li>Using an operation of the second type, she goes up 2<sup>1</sup> stairs to reach stair 2.</li> <li>Using an operation of the first type, she goes down 1 stair to reach stair 1.</li> </ul> </li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>0 &lt;= k &lt;= 10<sup>9</sup></code></li> </ul>
Bit Manipulation; Memoization; Math; Dynamic Programming; Combinatorics
Python
class Solution: def waysToReachStair(self, k: int) -> int: @cache def dfs(i: int, j: int, jump: int) -> int: if i > k + 1: return 0 ans = int(i == k) if i > 0 and j == 0: ans += dfs(i - 1, 1, jump) ans += dfs(i + (1 << jump), 0, jump + 1) return ans return dfs(1, 0, 0)
3,154
Find Number of Ways to Reach the K-th Stair
Hard
<p>You are given a <strong>non-negative</strong> integer <code>k</code>. There exists a staircase with an infinite number of stairs, with the <strong>lowest</strong> stair numbered 0.</p> <p>Alice has an integer <code>jump</code>, with an initial value of 0. She starts on stair 1 and wants to reach stair <code>k</code> using <strong>any</strong> number of <strong>operations</strong>. If she is on stair <code>i</code>, in one <strong>operation</strong> she can:</p> <ul> <li>Go down to stair <code>i - 1</code>. This operation <strong>cannot</strong> be used consecutively or on stair 0.</li> <li>Go up to stair <code>i + 2<sup>jump</sup></code>. And then, <code>jump</code> becomes <code>jump + 1</code>.</li> </ul> <p>Return the <em>total</em> number of ways Alice can reach stair <code>k</code>.</p> <p><strong>Note</strong> that it is possible that Alice reaches the stair <code>k</code>, and performs some operations to reach the stair <code>k</code> again.</p> <p>&nbsp;</p> <p><strong class="example">Example 1:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">k = 0</span></p> <p><strong>Output:</strong> <span class="example-io">2</span></p> <p><strong>Explanation:</strong></p> <p>The 2 possible ways of reaching stair 0 are:</p> <ul> <li>Alice starts at stair 1. <ul> <li>Using an operation of the first type, she goes down 1 stair to reach stair 0.</li> </ul> </li> <li>Alice starts at stair 1. <ul> <li>Using an operation of the first type, she goes down 1 stair to reach stair 0.</li> <li>Using an operation of the second type, she goes up 2<sup>0</sup> stairs to reach stair 1.</li> <li>Using an operation of the first type, she goes down 1 stair to reach stair 0.</li> </ul> </li> </ul> </div> <p><strong class="example">Example 2:</strong></p> <div class="example-block"> <p><strong>Input:</strong> <span class="example-io">k = 1</span></p> <p><strong>Output:</strong> <span class="example-io">4</span></p> <p><strong>Explanation:</strong></p> <p>The 4 possible ways of reaching stair 1 are:</p> <ul> <li>Alice starts at stair 1. Alice is at stair 1.</li> <li>Alice starts at stair 1. <ul> <li>Using an operation of the first type, she goes down 1 stair to reach stair 0.</li> <li>Using an operation of the second type, she goes up 2<sup>0</sup> stairs to reach stair 1.</li> </ul> </li> <li>Alice starts at stair 1. <ul> <li>Using an operation of the second type, she goes up 2<sup>0</sup> stairs to reach stair 2.</li> <li>Using an operation of the first type, she goes down 1 stair to reach stair 1.</li> </ul> </li> <li>Alice starts at stair 1. <ul> <li>Using an operation of the first type, she goes down 1 stair to reach stair 0.</li> <li>Using an operation of the second type, she goes up 2<sup>0</sup> stairs to reach stair 1.</li> <li>Using an operation of the first type, she goes down 1 stair to reach stair 0.</li> <li>Using an operation of the second type, she goes up 2<sup>1</sup> stairs to reach stair 2.</li> <li>Using an operation of the first type, she goes down 1 stair to reach stair 1.</li> </ul> </li> </ul> </div> <p>&nbsp;</p> <p><strong>Constraints:</strong></p> <ul> <li><code>0 &lt;= k &lt;= 10<sup>9</sup></code></li> </ul>
Bit Manipulation; Memoization; Math; Dynamic Programming; Combinatorics
TypeScript
function waysToReachStair(k: number): number { const f: Map<bigint, number> = new Map(); const dfs = (i: number, j: number, jump: number): number => { if (i > k + 1) { return 0; } const key: bigint = (BigInt(i) << BigInt(32)) | BigInt(jump << 1) | BigInt(j); if (f.has(key)) { return f.get(key)!; } let ans: number = 0; if (i === k) { ans++; } if (i > 0 && j === 0) { ans += dfs(i - 1, 1, jump); } ans += dfs(i + (1 << jump), 0, jump + 1); f.set(key, ans); return ans; }; return dfs(1, 0, 0); }