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287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
n = int(input()) mod = n % 4 if mod == 2 or mod == 3: print(-1) else: ans = [-1 for i in range(n)] i = 0 while i < n // 2: ans[i] = n - i - 1 ans[i+1] = i + 1 ans[n-1-i] = i + 2 ans[n-2-i] = n - i i += 2 if mod == 1: ans[n//2] = n//2 + 1 print(' '.join(map(str, ans)))
PYTHON3
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; const long long maxx = 1ll << 32; const int maxn = 100005; int n, k = 0, m, l, r, x, y, t; int a[maxn]; long long c[maxn]; int dp[maxn]; int vis[maxn]; int gcd(long long a, long long b) { return b == 0 ? a : gcd(b, a % b); } struct lee { int num; int x, y; } lo[maxn]; struct le { int v, sum; } lm[maxn]; char ss; string s1, s2; stack<long long> stackk; int main() { while (~scanf("%d", &n)) { if (n % 4 != 0 && n % 4 != 1) printf("-1\n"); else { int k = 1; for (int i = 1; i <= n; i++) vis[i] = 0; if (n & 1) a[n / 2 + 1] = n / 2 + 1; for (int i = n / 2; vis[i] == 0 && i; i--) { a[i] = k; a[n + 1 - k] = i; a[n + 1 - i] = n + 1 - k; a[k] = n + 1 - i; vis[i] = vis[n + 1 - k] = vis[n + 1 - i] = vis[k] = 1; k++; } for (int i = 1; i <= n; i++) i == n ? printf("%d\n", a[i]) : printf("%d ", a[i]); } } }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
import java.util.*; public class C { Scanner sc = new Scanner(System.in); void doIt() { int n = sc.nextInt(); if(n % 4 >= 2) System.out.println(-1); else { int [] ans = new int[n]; if(n % 4 == 1) ans[n / 2] = (n + 1) / 2; for(int i = 0; i < n / 2; i += 2 ){ ans[i] = i+2; ans[i+1] = n-i; ans[n-i-2] = i+1; ans[n-i-1] = n-i-1; //System.out.println(Arrays.toString(ans)); } StringBuilder sb = new StringBuilder(""); for(int i = 0; i < n; i++) sb.append(ans[i] + " "); System.out.println(sb); } } /** * @param args */ public static void main(String[] args) { new C().doIt(); } }
JAVA
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; int v[100010]; int main() { int n; while (cin >> n) { memset(v, 0, sizeof(v)); if (n % 4 == 2 || n % 4 == 3) { cout << -1 << endl; continue; } if (n == 1) { cout << 1 << endl; continue; } int m = n / 4; m <<= 1; int i; for (i = 1; i <= m; i += 2) { v[i] = i + 1; v[i + 1] = n - i + 1; v[n - i + 1] = n - i; v[n - i] = i; } if (n % 4 == 1) { v[i] = i; } for (int i = 1; i <= n; i++) { printf("%d ", v[i]); } cout << endl; } return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
n=int(input()) if(n%4>1): print(-1) else: ans=[0]*(n+1) i,j,a,b=1,n,1,n while(i<j and a<=n and b>=1): ans[i],ans[j]=a+1,b-1 ans[i+1],ans[j-1]=b,a i+=2 j-=2 a+=2 b-=2 if(i==j): ans[i]=a for i in range(1,n+1): print(ans[i],end=' ')
PYTHON3
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; void _ad(int &p) { static int i = 0; p = i++; } int n; int perm[100001] = {0}; bool checkit(vector<int> &a) { for (int i = 0; i < a.size(); i++) { if (a[a[i] - 1] != a.size() - i) return false; } return true; } void past(int l, int r, int mn, int mx) { perm[l] = mn + 1; perm[l + 1] = mx; perm[r - 1] = mx - 1; perm[r - 2] = mn; } int main() { cin >> n; if (n == 1) { cout << 1; return 0; } if (n < 4) { cout << -1; return 0; } if (n % 4 == 0 || n % 4 == 1) { int mn = 1; int mx = n; int l = 0, r = n; while (l < r - 1) { past(l, r, mn, mx); l += 2; r -= 2; mn += 2; mx -= 2; } if (n % 2 == 1) perm[n / 2] = mn; for (int i = 0; i < n; i++) { printf("%d ", perm[i]); } return 0; } cout << -1; return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.io.PrintWriter; import java.util.ArrayList; import java.util.Locale; import java.util.StringTokenizer; public class A { private void solve() throws IOException { int n = nextInt(); if (n % 4 == 2 || n % 4 == 3) { println("-1"); return; } int l = 0; int r = n - 1; int L = 1; int R = n; int[] a = new int[n]; int m = n; while (m >= 4) { a[l] = L + 1; a[l + 1] = R; a[r] = R - 1; a[r - 1] = L; l += 2; r -= 2; L += 2; R -= 2; m -= 4; } if (m == 1) { a[l] = l + 1; } for (int i: a) { print(i + " "); } } private String nextToken() throws IOException { while (tokenizer == null || !tokenizer.hasMoreTokens()) { tokenizer = new StringTokenizer(reader.readLine()); } return tokenizer.nextToken(); } private int nextInt() throws NumberFormatException, IOException { return Integer.parseInt(nextToken()); } private double nextDouble() throws NumberFormatException, IOException { return Double.parseDouble(nextToken()); } private long nextLong() throws IOException { return Long.parseLong(nextToken()); } private void print(Object o) { writer.print(o); } private void println(Object o) { writer.println(o); } private void printf(String format, Object... o) { writer.printf(format, o); } public static void main(String[] args) { long time = System.currentTimeMillis(); Locale.setDefault(Locale.US); new A().run(); System.err.printf("%.3f\n", 1e-3 * (System.currentTimeMillis() - time)); } BufferedReader reader; StringTokenizer tokenizer; PrintWriter writer; private void run() { try { reader = new BufferedReader(new InputStreamReader(System.in)); writer = new PrintWriter(System.out); solve(); reader.close(); writer.close(); } catch (IOException e) { e.printStackTrace(); System.exit(13); } } }
JAVA
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; const int Maxn = 101000; int a[Maxn]; int n; int main() { scanf("%d", &n); if ((n / 2) % 2 == 1) { printf("-1\n"); return 0; } for (int i1 = 1, i2 = 2, i3 = n - 1, i4 = n; i2 < i3;) { a[i1] = i2; a[i2] = i4; a[i4] = i3; a[i3] = i1; i1 += 2; i2 += 2; i3 -= 2; i4 -= 2; } if (n % 2 == 1) a[n / 2 + 1] = n / 2 + 1; for (int i = 1; i <= n; ++i) printf("%d ", a[i]); printf("\n"); return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; int n, a[100005], i; void Solve(int left, int right) { if (left > right) return; if (right - left < 3) { if (left == right) a[left] = right; if (left + 1 == right) a[left] = left, a[right] = right; if (left + 2 == right) a[left] = right, a[left + 1] = left + 1, a[right] = left; return; } a[left] = left + 1; a[left + 1] = right; a[right] = right - 1; a[right - 1] = left; Solve(left + 2, right - 2); } int main() { ios_base::sync_with_stdio(0); cin >> n; Solve(1, n); for (i = 1; i <= n; ++i) if (a[a[i]] != n - i + 1) return cout << "-1\n", 0; for (i = 1; i <= n; ++i) cout << a[i] << " \n"[i == n]; return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; const int max_n = 1e5 + 15; int n, p[max_n]; int main() { cin >> n; if ((n & 3) > 1) { cout << -1; return 0; } if (n == 1) { cout << 1; return 0; } for (int i = 0; i + i + 1 < n; i += 2) { p[i] = i + 2; p[n - i - 1] = n + 1 - p[i]; p[i + 1] = p[n - i - 1] + 1; p[n - i - 2] = n + 1 - p[i + 1]; } if (n & 1) p[n / 2] = n / 2 + 1; for (int i = 0; i < n; i++) cout << p[i] << " "; return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; long p[100001]; bool visit[100001]; long n; bool DFS(int i); int main(void) { ios::sync_with_stdio(false); cin.tie(NULL); cin >> n; if (n > 1) { memset(p, -1, sizeof(p)); memset(visit, false, sizeof(visit)); bool key = true; for (int i = 1; i <= n; i++) { if (!visit[i]) { if (i + 1 <= n && !visit[i + 1]) p[i] = i + 1; else p[i] = i; key = key && DFS(i); } } if (key) { for (int i = 1; i <= n; i++) cout << p[i] << " "; } else cout << "-1"; } else if (n == 1) cout << "1"; return 0; } bool DFS(int i) { long temp = n - i + 1; visit[i] = true; if (p[p[i]] == -1) { p[p[i]] = temp; return DFS(p[i]); } else if (p[p[i]] == temp) return true; else return false; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
import java.io.OutputStream; import java.io.IOException; import java.io.OutputStreamWriter; import java.io.PrintWriter; import java.io.BufferedWriter; import java.util.InputMismatchException; import java.io.Writer; import java.io.InputStream; /** * Built using CHelper plug-in * Actual solution is at the top * @author BSRK Aditya ([email protected]) */ public class Main { public static void main(String[] args) { InputStream inputStream = System.in; OutputStream outputStream = System.out; InputReader in = new InputReader(inputStream); OutputWriter out = new OutputWriter(outputStream); TaskA solver = new TaskA(); solver.solve(1, in, out); out.close(); } } class TaskA { public void solve(int testNumber, InputReader in, OutputWriter out) { int n = in.readInt(); if(n%4 <= 1) { int [] ans = new int[n]; for(int i = 1, j = 2; 2*i < n; i += 2, j += 2) { ans[j-1] = i; ans[i-1] = n+1-j; ans[n-j] = n+1-i; ans[n-i] = j; } if(n%4 == 1) ans[(n-1)/2] = (n-1)/2+1; for(int v : ans) out.print(v + " "); out.printLine(); } else { out.printLine(-1); } } } class InputReader { private InputStream stream; private byte[] buf = new byte[1024]; private int curChar; private int numChars; private SpaceCharFilter filter; public InputReader(InputStream stream) { this.stream = stream; } public int read() { if (numChars == -1) throw new InputMismatchException(); if (curChar >= numChars) { curChar = 0; try { numChars = stream.read(buf); } catch (IOException e) { throw new InputMismatchException(); } if (numChars <= 0) return -1; } return buf[curChar++]; } public int readInt() { int c = read(); while (isSpaceChar(c)) c = read(); int sgn = 1; if (c == '-') { sgn = -1; c = read(); } int res = 0; do { if (c < '0' || c > '9') throw new InputMismatchException(); res *= 10; res += c - '0'; c = read(); } while (!isSpaceChar(c)); return res * sgn; } public boolean isSpaceChar(int c) { if (filter != null) return filter.isSpaceChar(c); return isWhitespace(c); } public static boolean isWhitespace(int c) { return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1; } public interface SpaceCharFilter { public boolean isSpaceChar(int ch); } } class OutputWriter { private final PrintWriter writer; public OutputWriter(OutputStream outputStream) { writer = new PrintWriter(new BufferedWriter(new OutputStreamWriter(outputStream))); } public OutputWriter(Writer writer) { this.writer = new PrintWriter(writer); } public void print(Object...objects) { for (int i = 0; i < objects.length; i++) { if (i != 0) writer.print(' '); writer.print(objects[i]); } } public void printLine(Object...objects) { print(objects); writer.println(); } public void close() { writer.close(); } }
JAVA
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; const int N = 100005; int a[N]; int main() { int n, i; scanf("%d", &n); if (n % 4 == 2 || n % 4 == 3) printf("-1\n"); else { for (i = 1; i <= n / 2; i += 2) { a[i] = i + 1; a[i + 1] = n - i + 1; a[n - i] = i; a[n - i + 1] = n - i; } if (n % 4 == 1) a[n / 2 + 1] = n / 2 + 1; for (i = 1; i < n; i++) printf("%d ", a[i]); printf("%d\n", a[n]); } return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> int ans[100000]; int main() { int a; scanf("%d", &a); if (a % 4 == 2 || a % 4 == 3) { printf("-1\n"); return 0; } if (a % 4 == 0) { for (int i = 0; i < a / 4; i++) { ans[i * 2] = i * 2 + 2; ans[i * 2 + 1] = a - i * 2; ans[a - 1 - i * 2] = a - 1 - i * 2; ans[a - 2 - i * 2] = i * 2 + 1; } } else { for (int i = 0; i < a / 4; i++) { ans[i * 2] = i * 2 + 2; ans[i * 2 + 1] = a - i * 2; ans[a - 1 - i * 2] = a - 1 - i * 2; ans[a - 2 - i * 2] = i * 2 + 1; } ans[a / 2] = a / 2 + 1; } for (int i = 0; i < a; i++) printf("%d ", ans[i]); }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; int a, b, c, d, n, m, i, j, ans, l, r, lcnt = 1, rcnt; int ar[100005]; int main() { scanf("%d\n", &n); if (n % 4 > 1) { printf("-1\n"); return 0; } lcnt = 1, rcnt = n; l = 1, r = n; for (i = 0; i <= n - 4; i += 4) { ar[l++] = lcnt + 1; ar[l++] = rcnt; ar[r--] = rcnt - 1; ar[r--] = lcnt; lcnt += 2; rcnt -= 2; } if (n % 4 == 1) { ar[n / 2 + 1] = n / 2 + 1; } for (i = 1; i <= n; i++) { printf("%d ", ar[i]); } return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> int n; int f[100002]; void DP() { int i, x, y; for (i = 1; 2 * i <= n; i += 2) { x = i; y = i + 1; f[x] = y; f[y] = n - x + 1; f[n - x + 1] = n - y + 1; f[n - y + 1] = x; } if (n % 4) f[(n + 1) / 2] = (n + 1) / 2; for (i = 1; i < n; i++) printf("%d ", f[i]); printf("%d\n", f[n]); } int main() { while (~scanf("%d", &n)) { if (n == 1 || (n % 4) <= 1) DP(); else puts("-1"); } return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
import java.io.BufferedReader; import java.io.IOException; import java.io.InputStream; import java.io.InputStreamReader; import java.io.PrintWriter; import java.util.Scanner; import java.util.StringTokenizer; public class Main{ public static void main(String[] args) { Scanner r = new Scanner(System.in); PrintWriter out = new PrintWriter(System.out); int N = r.nextInt(); if(N % 4 == 0 || (N % 4 == 1)){ int[] a = new int[N]; int rem = N; if(N % 2 == 1)a[N / 2] = N / 2 + 1; for(int i = 0; i < N; i += 2){ if(rem < 4)break; a[i] = (i + 1) + 1; a[i + 1] = N - i - 1 + 1; a[m(i, N) - 1] = i + 1; a[m(i, N)] = m(i, N) - 1 + 1; rem -= 4; } for(int i = 0; i < N; i++) out.println(a[i]); }else{ out.println(-1); } out.close(); } private static int m(int i, int N) { return N - i - 1; } static class InputReader { private BufferedReader reader; private StringTokenizer tokenizer; public InputReader(InputStream stream) { reader = new BufferedReader(new InputStreamReader(stream)); tokenizer = null; } public String nextLine(){ try { return reader.readLine(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); return null; } } public String next() { while (tokenizer == null || !tokenizer.hasMoreTokens()) { try { tokenizer = new StringTokenizer(reader.readLine()); } catch (IOException e) { throw new RuntimeException(e); } } return tokenizer.nextToken(); } public int nextInt() { return Integer.parseInt(next()); } public long nextLong() { return Long.parseLong(next()); } } }
JAVA
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; int main() { long long int n, i; cin >> n; if (n % 4 != 1 && n % 4 != 0) { cout << "-1"; return 0; } long long int a[n]; for (i = 0; i < n / 4; i++) { a[2 * i] = 2 * i + 2; a[2 * i + 1] = n - 2 * i; a[n - 2 * i - 1] = n - 2 * i - 1; a[n - 2 * i - 2] = 2 * i + 1; } if (n % 4 == 1) { a[n / 2] = n / 2 + 1; } for (i = 0; i < n; i++) cout << a[i] << " "; return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
import java.util.*; import java.io.*; public class a { static long mod = 1000000007; public static void main(String[] args) throws IOException { input.init(System.in); PrintWriter out = new PrintWriter(new OutputStreamWriter(System.out)); int n = input.nextInt(); int[] res = new int[n+1]; if(n%4 == 2 || n%4 == 3) { out.println(-1); } else if(n%4 == 1) { res[(n+1)/2] = (n+1)/2; int at = (n+1)/2; for(int i = 0; i<n/4; i++) { res[at+1+2*i] = res[at]-2-2*i; res[at+2+2*i] = res[at]+1+2*i; res[at-1-2*i] = res[at]+2+2*i; res[at-2-2*i] = res[at]-1-2*i; } for(int i = 1; i<=n; i++) out.print(res[i]+" "); } else if(n%4 == 0) { int at = n/2; res[at] = n/2+2; for(int i = 0; i<n/4; i++) { res[at+1+2*i] = res[at]-3-2*i; res[at-2*i] = res[at]+2*i; res[at-1-2*i] = res[at]-2-2*i; res[at+2+2*i] = res[at]-1+2*i; } for(int i = 1; i<=n; i++) out.print(res[i]+" "); } out.close(); } //static long gcd(long a, long b) //{ // if(b==0) return a; // return gcd(b,a%b); //} //static long choose(int n, int k) //{ // long num = 1, denom = 1; // for(int i = 0; i<k; i++) // { // num = (num*(n-i))%mod; // denom = (denom*(k-i))%mod; // } // return (num * modinv(denom, mod))%mod; //} //static long[] gcd(long p, long q) { // if (q == 0) // return new long[] { p, 1, 0 }; // long[] vals = gcd(q, p % q); // long d = vals[0]; // long a = vals[2]; // long b = vals[1] - (p / q) * vals[2]; // return new long[] { d, a, b }; //} // //static long modinv(long k, long n) { // long[] vals = gcd(k, n); // long d = vals[0]; // long a = vals[1]; // long b = vals[2]; // if (a > 0) return a; // return n + a; //} static class input { static BufferedReader reader; static StringTokenizer tokenizer; /** call this method to initialize reader for InputStream */ static void init(InputStream input) { reader = new BufferedReader( new InputStreamReader(input) ); tokenizer = new StringTokenizer(""); } /** get next word */ static String next() throws IOException { while ( ! tokenizer.hasMoreTokens() ) { //TODO add check for eof if necessary tokenizer = new StringTokenizer( reader.readLine() ); } return tokenizer.nextToken(); } static int nextInt() throws IOException { return Integer.parseInt( next() ); } static long nextLong() throws IOException { return Long.parseLong( next() ); } static double nextDouble() throws IOException { return Double.parseDouble( next() ); } static String nextLine() throws IOException { return reader.readLine(); } } }
JAVA
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; int DEBUG = 0; int main(int argc, char **argv) { DEBUG = (argc >= 2) ? atoi(argv[1]) : 0; int n; scanf("%d", &n); if (n == 1) { cout << 1 << endl; return 0; } if ((n % 4) == 0 || (n % 4) == 1) { int k = n / 4; for (int i = 1; i <= k; i++) { cout << (2 * i) << " " << (n - 2 * (i - 1)) << " "; } if (n == (4 * k + 1)) { cout << (2 * k + 1) << " "; } for (int i = k; i >= 1; i--) { cout << (2 * i - 1) << " " << (n - (2 * i - 1)) << " "; } cout << endl; } else { cout << -1 << endl; } return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; int P[100010]; int main(int argc, const char *argv[]) { int n; cin >> n; if (n % 4 == 2 || n % 4 == 3) { cout << -1; return 0; } for (int i = 1; i <= (n - 1) / 2; i += 2) { P[i] = i + 1; for (int j = i; P[P[j]] == 0; j = P[j]) { P[P[j]] = n - j + 1; } } if (n % 4 == 1) P[(n + 1) / 2] = (n + 1) / 2; for (int i = 1; i <= n; i++) cout << P[i] << ' '; return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#import itertools #def isok(l, n): # for i in range(1, n+1): # if l[l[i-1]-1] != n - i + 1: # return False # return True n = int(raw_input()) #ok = 0 #for l in itertools.permutations([i for i in range(1, n+1)]): # if isok(l, n): # ok = 1 # print ' '.join(str(i) for i in l) # break #if ok == 0: # print -1 if n % 4 == 2 or n % 4 == 3: print -1 exit() a = [0]*(n+1) if n%2 == 1: a[n/2+1] = n/2+1 for i in range(1, n/2, 2): a[i] = i+1 a[i+1] = n-i+1 a[n-i+1] = n-i a[n-i] = i print ' '.join(map(str, a[1:]))
PYTHON
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; int outpu[100001]; set<int> se; set<int>::iterator it; int n; int main() { cin >> n; bool k = 0; if ((n - 1) % 4 == 0) { k = 1; outpu[n / 2 + 1] = n / 2 + 1; } if (n % 4 == 0 || n % 4 == 1) { for (int i = 1; i <= n; i++) if (k == 0 || (k == 1 && i != n / 2 + 1)) se.insert(i); for (int i = 1; i <= n; i++) if (outpu[i] == 0) { for (it = se.begin(); it != se.end(); it++) if (((*it) != i) && (*it) != (n - i + 1)) break; int j = i; outpu[j] = (*it); se.erase(*it); while (1) { outpu[outpu[j]] = (n - j + 1); j = outpu[j]; se.erase(j); if (j == i) break; } } for (int i = 1; i <= n; i++) { cout << outpu[i] << ' '; } cout << endl; } else { cout << "-1" << endl; } return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
import java.io.IOException; import java.util.InputMismatchException; public class LuckyPermutation { public static void main(String[] args) { FasterScanner sc = new FasterScanner(); int N = sc.nextInt(); if (N % 4 == 2 || N % 4 == 3) { System.out.println(-1); return; } int[] arr = new int[N + 1]; int L = 1; int R = N; for (int i = 0; i < N / 4; i++) { arr[L] = L + 1; arr[L + 1] = R; arr[R] = R - 1; arr[R - 1] = L; L += 2; R -= 2; } if (N % 2 == 1) { arr[N / 2 + 1] = N / 2 + 1; } StringBuilder sb = new StringBuilder(); for (int i = 1; i <= N; i++) { sb.append(arr[i] + " "); } System.out.println(sb.toString()); } public static class FasterScanner { private byte[] buf = new byte[1024]; private int curChar; private int numChars; public int read() { if (numChars == -1) throw new InputMismatchException(); if (curChar >= numChars) { curChar = 0; try { numChars = System.in.read(buf); } catch (IOException e) { throw new InputMismatchException(); } if (numChars <= 0) return -1; } return buf[curChar++]; } public String nextLine() { int c = read(); while (isSpaceChar(c)) c = read(); StringBuilder res = new StringBuilder(); do { res.appendCodePoint(c); c = read(); } while (!isEndOfLine(c)); return res.toString(); } public String nextString() { int c = read(); while (isSpaceChar(c)) c = read(); StringBuilder res = new StringBuilder(); do { res.appendCodePoint(c); c = read(); } while (!isSpaceChar(c)); return res.toString(); } public long nextLong() { int c = read(); while (isSpaceChar(c)) c = read(); int sgn = 1; if (c == '-') { sgn = -1; c = read(); } long res = 0; do { if (c < '0' || c > '9') throw new InputMismatchException(); res *= 10; res += c - '0'; c = read(); } while (!isSpaceChar(c)); return res * sgn; } public int nextInt() { int c = read(); while (isSpaceChar(c)) c = read(); int sgn = 1; if (c == '-') { sgn = -1; c = read(); } int res = 0; do { if (c < '0' || c > '9') throw new InputMismatchException(); res *= 10; res += c - '0'; c = read(); } while (!isSpaceChar(c)); return res * sgn; } public int[] nextIntArray(int n) { int[] arr = new int[n]; for (int i = 0; i < n; i++) { arr[i] = nextInt(); } return arr; } public long[] nextLongArray(int n) { long[] arr = new long[n]; for (int i = 0; i < n; i++) { arr[i] = nextLong(); } return arr; } private boolean isSpaceChar(int c) { return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1; } private boolean isEndOfLine(int c) { return c == '\n' || c == '\r' || c == -1; } } }
JAVA
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
from collections import Counter from itertools import cycle, product as prod, permutations as perm, combinations as comb, combinations_with_replacement as combr from sys import stdin, stdout read_ints = lambda: map(int, raw_input().split()) read_floats = lambda: map(float, raw_input().split()) def main(): n = input() b = [None] * (n + 1) cur = 1 if n % 4 == 0: for i in xrange(1, n/2+1, 2): o = [i, i+1, n-i+1, n-i] for j in xrange(4): b[o[j]] = o[j+1 & 3] print ' '.join(map(str, b[1:])) elif n % 4 == 1: for i in xrange(1, n/2+1, 2): o = [i, i+1, n-i+1, n-i] for j in xrange(4): b[o[j]] = o[j+1 & 3] b[n/2+1] = n/2+1 print ' '.join(map(str, b[1:])) else: print -1 if __name__ == '__main__': main()
PYTHON
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; long long INV2 = 500000004; long long INV6 = 166666668; long long power(long long a, long long b, long long c) { long long x = 1, y = a; while (b > 0) { if (b & 1) x = (x * y) % c; y = (y * y) % c; b /= 2; } return x % c; } int dx[] = {0, -1, 0, 1}; int dy[] = {-1, 0, 1, 0}; int dr[] = {1, 1, 0, -1, -1, -1, 0, 1}; int dc[] = {0, 1, 1, 1, 0, -1, -1, -1}; int ans[100005]; bool fl; int has[100005]; int main() { int n; scanf("%d", &n); if (n == 2 || n == 3 || n == 6) { printf("-1\n"); } else { int mid = n / 2 + 1; if (n & 1) { ans[mid] = mid; for (int i = 1; i < mid; i += 2) { ans[i] = i + 1; has[i + 1]++; if (has[i + 1] > 1) fl = 1; } int val = n; for (int i = 2; i < mid; i += 2) { ans[i] = val; val -= 2; has[val]++; if (has[val] > 1) fl = 1; } for (int i = n; i > mid; i -= 2) { ans[i] = i - 1; has[i - 1]++; if (has[i - 1] > 1) fl = 1; } val = 1; for (int i = n - 1; i > mid; i -= 2) { ans[i] = val; has[val]++; if (has[val] > 1) fl = 1; val += 2; } } else { mid = n / 2; for (int i = 1; i <= mid; i += 2) { ans[i] = i + 1; has[i + 1]++; if (has[i + 1] > 1) fl = 1; } int val = n; for (int i = 2; i <= mid; i += 2) { ans[i] = val; has[val]++; if (has[val] > 1) fl = 1; val -= 2; } for (int i = n; i > mid; i -= 2) { ans[i] = i - 1; has[i - 1]++; if (has[i - 1] > 1) fl = 1; } val = 1; for (int i = n - 1; i > mid; i -= 2) { ans[i] = val; has[val]++; if (has[val] > 1) fl = 1; val += 2; } } for (int i = 1; i <= n; ++i) { if (ans[ans[i]] != (n - i + 1)) { fl = 1; break; } } if (fl) { printf("-1\n"); return 0; } for (int i = 1; i <= n; ++i) { printf("%d ", ans[i]); } printf("\n"); } return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; inline bool iseq(double x, double y) { if (fabs(x - y) < 1e-8) return true; return false; } template <typename T> inline T hpt(T x1, T y1, T x2, T y2) { return hypot(x1 - x2, y1 - y2); } template <typename T> inline T gcd(T a, T b) { if (!b) return a; else return gcd(b, a % b); } template <typename T> inline void extended_euclid(T a, T b, T &x, T &y) { if (a % b == 0) x = 0, y = 1; else { extended_euclid(b, a % b, x, y); T temp = x; x = y; y = -y * (a / b) + temp; } } template <typename T> inline T bigmod(T b, T p, T m) { if (!p) return 1; else if (!(p % 2)) { T x = bigmod(b, p / 2, m); return x * x; } else return ((b % m) * bigmod(b, p - 1, m)) % m; } int prime[5 / 32 + 1]; void setbit(int i) { int p = i >> 5, q = i & 31; prime[p] |= (1 << q); } bool checkbit(int i) { int p = i >> 5, q = i & 31; return prime[p] & (1 << q) ? true : false; } void buildprime(int n) { int i, j, k = sqrt(double(n)); prime[0] = 3; for (i = 4; i < n; i += 2) setbit(i); for (i = 3; i <= k; i += 2) { if (!checkbit(i)) { int ii = i + i; for (j = i * i; j < n; j += ii) setbit(j); } } } int sum, r, n, N, R, C; int val[150005]; int main() { int i, j, k; while (scanf("%d", &n) == 1) { if (n % 4 > 1) { printf("-1\n"); continue; } list<int> L; for (int i = 1; i <= n; ++i) L.push_back(i); int beg = 0; int end_ = n - 1; while (!L.empty()) { if (beg == end_) { val[beg] = L.front(); L.pop_front(); break; } int f1 = L.front(); L.pop_front(); int f2 = L.front(); L.pop_front(); int e1 = L.back(); L.pop_back(); int e2 = L.back(); L.pop_back(); val[beg] = f2; val[beg + 1] = e1; val[end_] = e2; val[end_ - 1] = f1; beg += 2; end_ -= 2; } for (int i = 0; i < n; ++i) cout << val[i] << " "; cout << endl; } return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> int a[100001]; int main() { int i, n; scanf("%d", &n); if (n % 4 == 2 || n % 4 == 3) puts("-1"); else { for (i = 1; i <= n / 4; i++) { a[2 * i - 1] = 2 * i; a[2 * i] = n - 2 * i + 2; a[n - 2 * i + 2] = n - 2 * i + 1; a[n - 2 * i + 1] = 2 * i - 1; } if (n % 2) a[n / 2 + 1] = n / 2 + 1; for (i = 1; i <= n; i++) printf("%d ", a[i]); } }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; int n, num[100005]; int main() { cin >> n; if (!(n % 4 == 0 || n % 4 == 1)) { cout << -1 << endl; return 0; } int st = 1, en = n, cnt = 0; while (1) { if (cnt * 4 == n) break; if (cnt * 4 + 1 == n) { num[st] = st; break; } num[st] = st + 1; num[st + 1] = en; num[en] = en - 1; num[en - 1] = st; st = st + 2; en = en - 2; cnt++; } for (int i = 0; i < n; i++) cout << num[i + 1] << " "; return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
n = int(input()) if n%4 > 1: print(-1) else: a = [n+1>>1]*n for i in range(n//4): j = i*2 a[j], a[j+1], a[-2-j], a[-1-j] = j+2, n-j, j+1, n-1-j print(' '.join(map(str, a)))
PYTHON3
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
import java.io.IOException; import java.io.InputStream; import java.io.PrintWriter; import java.util.Arrays; import java.util.HashSet; import java.util.InputMismatchException; import java.util.LinkedList; public class B { static int N; static PrintWriter out; public static void main(String[] args) { MScanner sc = new MScanner(); out = new PrintWriter(System.out); int N = sc.nextInt(); if(N%4>1){ out.println(-1); out.close(); return; } LinkedList<Integer> start = new LinkedList<Integer>(); if(N%4==1)start.add(1); else{ start.add(2); start.add(4); start.add(1); start.add(3); } while(start.size()!=N){ int s = start.size(); start.addFirst(s+4); start.addFirst(2); start.addLast(1); start.addLast(s+3); } LinkedList<Integer> outputL = new LinkedList<Integer>(); LinkedList<Integer> outputR = new LinkedList<Integer>(); int val = 0; while(!start.isEmpty()){ if(start.size()<4){ while(!start.isEmpty()){ outputL.add(start.poll()+val); } } else{ outputL.addLast(start.poll()+val); outputL.addLast(start.poll()+val); outputR.addFirst(start.pollLast()+val); outputR.addFirst(start.pollLast()+val); val+=2; } } for(Integer x : outputL)out.print(x+" "); for(Integer x : outputR)out.print(x+" "); out.close(); } static class MScanner { private InputStream stream; private byte[] buf = new byte[1024]; private int curChar; private int numChars; public MScanner() { stream = System.in; // stream = new FileInputStream(new File("dec.in")); } int read() { if (numChars == -1) throw new InputMismatchException(); if (curChar >= numChars) { curChar = 0; try { numChars = stream.read(buf); } catch (IOException e) { throw new InputMismatchException(); } if (numChars <= 0) return -1; } return buf[curChar++]; } boolean isSpaceChar(int c) { return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1; } boolean isEndline(int c) { return c == '\n' || c == '\r' || c == -1; } int nextInt() { return Integer.parseInt(next()); } int[] nextInt(int N) { int[] ret = new int[N]; for (int a = 0; a < N; a++) ret[a] = nextInt(); return ret; } int[][] nextInt(int N, int M) { int[][] ret = new int[N][M]; for (int a = 0; a < N; a++) ret[a] = nextInt(M); return ret; } long nextLong() { return Long.parseLong(next()); } long[] nextLong(int N) { long[] ret = new long[N]; for (int a = 0; a < N; a++) ret[a] = nextLong(); return ret; } double nextDouble() { return Double.parseDouble(next()); } double[] nextDouble(int N) { double[] ret = new double[N]; for (int a = 0; a < N; a++) ret[a] = nextDouble(); return ret; } String next() { int c = read(); while (isSpaceChar(c)) c = read(); StringBuilder res = new StringBuilder(); do { res.appendCodePoint(c); c = read(); } while (!isSpaceChar(c)); return res.toString(); } String[] next(int N) { String[] ret = new String[N]; for (int a = 0; a < N; a++) ret[a] = next(); return ret; } String nextLine() { int c = read(); while (isEndline(c)) c = read(); StringBuilder res = new StringBuilder(); do { res.appendCodePoint(c); c = read(); } while (!isEndline(c)); return res.toString(); } String[] nextLine(int N) { String[] ret = new String[N]; for (int a = 0; a < N; a++) ret[a] = nextLine(); return ret; } } }
JAVA
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> int n; int main() { scanf("%d", &n); if (n % 4 == 2 || n % 4 == 3) { printf("-1\n"); return 0; } if (n % 4) { for (int i = 0; i < n / 2; ++i) { if (i) printf(" "); if (i & 1) printf("%d", n - i + 1); else printf("%d", i + 2); } if (n / 2) printf(" "); printf("%d", n / 2 + 1); for (int i = n / 2 + 1; i < n; ++i) { printf(" "); if (i & 1) printf("%d", n - i - 1); else printf("%d", i); } } else { for (int i = 0; i < n / 2; ++i) { if (i) printf(" "); if (i & 1) printf("%d", n - i + 1); else printf("%d", i + 2); } for (int i = n / 2; i < n; ++i) { printf(" "); if (i & 1) printf("%d", i); else printf("%d", n - i - 1); } } printf("\n"); return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
import java.io.BufferedReader; import java.io.InputStreamReader; import java.io.PrintWriter; import java.util.Arrays; import java.util.HashSet; import java.util.StringTokenizer; import static java.lang.Math.*; import static java.lang.Integer.*; import static java.lang.Long.*; import static java.lang.Character.*; @SuppressWarnings("unused") public class round176C { static BufferedReader br = new BufferedReader(new InputStreamReader( System.in)); static StringTokenizer st = new StringTokenizer(""); static int nextInt() throws Exception { return Integer.parseInt(next()); } static String next() throws Exception { while (true) { if (st.hasMoreTokens()) { return st.nextToken(); } String s = br.readLine(); if (s == null) { return null; } st = new StringTokenizer(s); } } public static void main(String[] args) throws Exception { PrintWriter out = new PrintWriter(System.out); int n = nextInt(); if(n % 4 == 2 || n % 4 == 3){ out.println(-1); out.flush(); return; } int [] ans = new int [n + 1]; int mx = n; int mn = 1; for(int i = 0 ; i < n / 4 ; ++i){ ans[mn] = mn + 1; ans[mn + 1] = mx; ans[mx] = mx - 1; ans[mx - 1] = mn; mx -= 2; mn += 2; } if(n % 4 == 1){ ans[n / 2 + 1] = n / 2 + 1; } for(int i = 1 ; i < n + 1 ; ++i){ out.print(ans[i] + " "); } out.flush(); } }
JAVA
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
import static java.util.Arrays.deepToString; import java.io.*; import java.math.*; import java.util.*; public class A { static void solve() { int n = nextInt(); int pairs = n / 2; if (pairs % 2 == 1) { writer.println(-1); return; } int[] p = new int[n + 1]; if (n % 2 == 1) { p[n / 2 + 1] = n / 2 + 1; } for (int it = 0; it < pairs / 2; it++) { int i = 2 * it + 1; p[i] = i + 1; p[i + 1] = n - i + 1; p[n - i + 1] = n - i; p[n - i] = i; } for (int i = 1; i <= n; i++) { writer.print(p[i] + " "); } } public static void main(String[] args) throws Exception { reader = new BufferedReader(new InputStreamReader(System.in)); writer = new PrintWriter(System.out); Locale.setDefault(Locale.US); setTime(); solve(); printTime(); printMemory(); writer.close(); } static BufferedReader reader; static PrintWriter writer; static StringTokenizer tok = new StringTokenizer(""); static long systemTime; static void debug(Object... o) { System.err.println(deepToString(o)); } static void setTime() { systemTime = System.currentTimeMillis(); } static void printTime() { System.err.println("Time consumed: " + (System.currentTimeMillis() - systemTime)); } static void printMemory() { System.err.println("Memory consumed: " + (Runtime.getRuntime().totalMemory() - Runtime.getRuntime().freeMemory()) / 1000 + "kb"); } static String next() { while (!tok.hasMoreTokens()) { String w = null; try { w = reader.readLine(); } catch (Exception e) { e.printStackTrace(); } if (w == null) return null; tok = new StringTokenizer(w); } return tok.nextToken(); } static int nextInt() { return Integer.parseInt(next()); } static long nextLong() { return Long.parseLong(next()); } static double nextDouble() { return Double.parseDouble(next()); } static BigInteger nextBigInteger() { return new BigInteger(next()); } }
JAVA
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; int dx[] = {0, 1, 0, -1, -1, -1, 1, 1}; int dy[] = {1, 0, -1, 0, 1, -1, 1, -1}; int res[100010]; bool vis[100010]; int main() { ios::sync_with_stdio(false); int n; cin >> n; if (n == 1) cout << 1; else { int co = 1; if (n & 1) vis[n / 2 + 1] = res[n / 2 + 1] = n / 2 + 1; if ((n / 2) % 4 != 2 && (n / 2) % 4 != 0) { cout << -1 << endl; return 0; } for (long long i = 1; i < n + 1; i++) { if (vis[i]) continue; int x = n - i + 1; res[i] = i + 1; while (!vis[i]) { vis[i] = 1; int x = n - i + 1; res[res[i]] = x; i = res[i]; } } for (long long i = 1; i < n + 1; i++) cout << res[i] << " "; } return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
import static java.lang.Math.*; import static java.lang.System.currentTimeMillis; import static java.lang.System.exit; import static java.lang.System.arraycopy; import static java.util.Arrays.sort; import static java.util.Arrays.binarySearch; import static java.util.Arrays.fill; import java.util.*; import java.io.*; public class Main { public static void main(String[] args) throws IOException { new Main().run(); } BufferedReader in; PrintWriter out; StringTokenizer st = new StringTokenizer(""); final int maxn = 100100; int n; int a[] = new int[maxn]; private void run() throws IOException { in = new BufferedReader(new InputStreamReader(System.in));//new FileReader("input.txt")); out = new PrintWriter(System.out);//"output.txt"); n = nextInt(); if ((n - n % 2) % 4 != 0) out.println("-1\n"); else { if (n % 2 == 1) a[n / 2 + 1] = n / 2 + 1; int l = 1; int r = n; while (r - l + 1 >= 4) { a[l] = l + 1; a[l + 1] = r; a[r - 1] = l; a[r] = r - 1; l += 2; r -= 2; } for (int i = 1; i <= n; i++) out.print(a[i] + " "); out.println(); } in.close(); out.close(); } void chk(boolean b) { if (b) return; System.out.println(new Error().getStackTrace()[1]); exit(999); } void deb(String fmt, Object... args) { System.out.printf(Locale.US, fmt + "%n", args); } String nextToken() throws IOException { while (!st.hasMoreTokens()) st = new StringTokenizer(in.readLine()); return st.nextToken(); } int nextInt() throws IOException { return Integer.parseInt(nextToken()); } long nextLong() throws IOException { return Long.parseLong(nextToken()); } double nextDouble() throws IOException { return Double.parseDouble(nextToken()); } String nextLine() throws IOException { st = new StringTokenizer(""); return in.readLine(); } boolean EOF() throws IOException { while (!st.hasMoreTokens()) { String s = in.readLine(); if (s == null) return true; st = new StringTokenizer(s); } return false; } }
JAVA
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; const int N = 100010; int n, p[N]; void Read_in() { scanf("%d", &n); return; } void Put_out() { if (n % 4 == 2 || n % 4 == 3) { printf("-1\n"); return; } for (int i = 1; i <= n; i++) { printf("%d", p[i]); if (i != n) printf(" "); else printf("\n"); } return; } void QAQ() { if (n % 4 == 2 || n % 4 == 3) return; for (int i = 1; i <= n / 2; i++) { if (i % 2) p[i] = i + 1, p[n - i + 1] = n - i; else p[i] = n - i + 2, p[n - i + 1] = i - 1; } if (n % 4 == 1) p[n / 2 + 1] = n / 2 + 1; return; } int main() { Read_in(); QAQ(); Put_out(); return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; const int maxn = 1e5 + 2; int a[maxn]; int n; int main() { ios_base::sync_with_stdio(0); cin >> n; int t = n % 4; for (int i = 1; i <= n; i++) a[i] = i; if (t == 1 or !t) { int pt1 = 1; int pt2 = n; while (pt1 < pt2) { swap(a[pt1], a[pt1 + 1]); swap(a[pt2], a[pt2 - 1]); swap(a[pt2 - 1], a[pt1 + 1]); pt2 -= 2; pt1 += 2; } for (int i = 1; i <= n; i++) cout << a[i] << ' '; } else cout << -1; return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; int n; int a[1000020]; int main() { cin >> n; if (n == 1) { puts("1"); } else if (n % 4 == 2 || n % 4 == 3) { puts("-1"); } else { for (int i = 0; i < n / 2; i++) if (i % 2 == 0) { a[i] = i + 1; a[i + 1] = n - 1 - i; a[n - 2 - i] = i; a[n - 1 - i] = n - 2 - i; } if (n & 1) a[n / 2] = n / 2; for (int i = 0; i < n; i++) printf("%d ", a[i] + 1); } }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
import java.io.BufferedReader; import java.io.InputStreamReader; import java.util.Arrays; import java.util.StringTokenizer; public class CodeA { static class Scanner { BufferedReader br = new BufferedReader(new InputStreamReader(System.in)); StringTokenizer st = new StringTokenizer(""); public String nextLine() { try { return br.readLine(); } catch(Exception e) { throw(new RuntimeException()); } } public String next() { while(!st.hasMoreTokens()) { String l = nextLine(); if(l == null) return null; st = new StringTokenizer(l); } return st.nextToken(); } public int nextInt() { return Integer.parseInt(next()); } public long nextLong() { return Long.parseLong(next()); } public double nextDouble() { return Double.parseDouble(next()); } public int[] nextIntArray(int n) { int[] res = new int[n]; for(int i = 0; i < res.length; i++) res[i] = nextInt(); return res; } public long[] nextLongArray(int n) { long[] res = new long[n]; for(int i = 0; i < res.length; i++) res[i] = nextLong(); return res; } public double[] nextDoubleArray(int n) { double[] res = new double[n]; for(int i = 0; i < res.length; i++) res[i] = nextLong(); return res; } public void sortIntArray(int[] array) { Integer[] vals = new Integer[array.length]; for(int i = 0; i < array.length; i++) vals[i] = array[i]; Arrays.sort(vals); for(int i = 0; i < array.length; i++) array[i] = vals[i]; } public void sortLongArray(long[] array) { Long[] vals = new Long[array.length]; for(int i = 0; i < array.length; i++) vals[i] = array[i]; Arrays.sort(vals); for(int i = 0; i < array.length; i++) array[i] = vals[i]; } public void sortDoubleArray(double[] array) { Double[] vals = new Double[array.length]; for(int i = 0; i < array.length; i++) vals[i] = array[i]; Arrays.sort(vals); for(int i = 0; i < array.length; i++) array[i] = vals[i]; } } static int[] permutation; public static boolean poner(int n, int val) { if(permutation[n] != 0) { if(permutation[n] != val) return false; return true; } else { permutation[n] = val; return poner(val, (permutation.length - 1) - n + 1); } } public static boolean intentar(int n) { permutation = new int[n + 1]; if(n == 1) { permutation[1] = 1; return true; } for(int i = 1; permutation[i] == 0; i += 2) { if(!poner(i, i + 1)) { permutation[i] = 0; if(!poner(i, i)) return false; return true; } } return true; } public static void main(String[] args) { Scanner sc = new Scanner(); int n = sc.nextInt(); if(intentar(n)) { for(int i = 1; i < permutation.length; i++) System.out.print((i == 1 ? "" : " ") + permutation[i]); System.out.println(); } else System.out.println(-1); } }
JAVA
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
import java.io.OutputStream; import java.io.IOException; import java.io.PrintWriter; import java.util.InputMismatchException; import java.util.LinkedList; import java.io.InputStream; /** * Built using CHelper plug-in * Actual solution is at the top * @author George Marcus */ public class Main { public static void main(String[] args) { InputStream inputStream = System.in; OutputStream outputStream = System.out; InputReader in = new InputReader(inputStream); PrintWriter out = new PrintWriter(outputStream); TaskC solver = new TaskC(); solver.solve(1, in, out); out.close(); } } class TaskC { int[] A; int N; public void solve(int testNumber, InputReader in, PrintWriter out) { N = in.nextInt(); if(N % 4 > 1) { out.println(-1); return; } LinkedList<Integer> left = new LinkedList<Integer>(); for(int i = 1; i <= N; i++) left.addLast(i); A = new int[N + 1]; if(N % 2 == 1) A[N / 2 + 1] = N / 2 + 1; boolean odd = N % 2 == 1; for(int i = 1; i <= N; i++) { if(odd && i == N / 2 + 1) continue; if(A[i] == 0) { int other = N - i + 1; int k; for(int j = 0; ; j++) { k = left.get(j); if(A[k] != 0) { left.remove(j); j--; continue; } if(k != i && k != other) { left.remove(j); break; } } A[i] = k; A[k] = other; go(k); } } for(int i = 1; i <= N; i++) out.print(A[i] + " "); } private void go(int k) { if(A[A[k]] == 0) { A[A[k]] = N - k + 1; go(A[k]); } } } class InputReader { private InputStream stream; private byte[] buf = new byte[1024]; private int curChar; private int numChars; public InputReader(InputStream stream) { this.stream = stream; } public int read() { if (numChars == -1) throw new InputMismatchException(); if (curChar >= numChars) { curChar = 0; try { numChars = stream.read(buf); } catch (IOException e) { throw new InputMismatchException(); } if (numChars <= 0) return -1; } return buf[curChar++]; } public int nextInt() { return Integer.parseInt(nextString()); } public String nextString() { int c = read(); while (isSpaceChar(c)) c = read(); StringBuffer res = new StringBuffer(); do { res.appendCodePoint(c); c = read(); } while (!isSpaceChar(c)); return res.toString(); } private boolean isSpaceChar(int c) { return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1; } }
JAVA
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; int main() { ios::sync_with_stdio(0); cin.tie(0); cout.tie(0); int n; cin >> n; if (n == 1) return cout << "1", 0; if (n % 4 > 1) return cout << "-1", 0; vector<int> ats, le, ri, add(n + 5); int mx, l, r; if (n % 4 == 0) { ats = {2, 4, 1, 3}; n -= 4; mx = 4; l = n / 2 + 1; r = n / 2 + 4; } else { ats = {1}; n -= 1; mx = 1; l = n / 2 + 1; r = n / 2 + 1; } while (n > 0) { mx += 4; n -= 4; le.push_back(mx); le.push_back(2); ri.push_back(1); ri.push_back(mx - 1); add[l] += 2; add[r + 1] -= 2; l -= 2; r += 2; } reverse(le.begin(), le.end()); reverse(ats.begin(), ats.end()); reverse(ri.begin(), ri.end()); while (!ats.empty()) le.push_back(ats.back()), ats.pop_back(); while (!ri.empty()) le.push_back(ri.back()), ri.pop_back(); for (int i = 0; i < le.size(); i++) { add[i + 1] += add[i]; cout << le[i] + add[i + 1] << " "; } }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; template <typename T> inline T abs(T t) { return t < 0 ? -t : t; } const long long modn = 1000000007; inline long long mod(long long x) { return x % modn; } int main() { int n, i, p[100005]; scanf("%d", &n); if (n == 1) { puts("1"); return 0; } if (n % 4 == 2 || n % 4 == 3) { puts("-1"); return 0; } for (i = 1; i <= n / 2; i++) if (i % 2) p[i] = i + 1, p[n - i + 1] = n - i; else p[i] = n - i + 2, p[n - i + 1] = i - 1; if (n % 4) p[n / 2 + 1] = n / 2 + 1; for (i = 1; i <= n; i++) printf("%d ", p[i]); putchar('\n'); return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; int f[100500]; int main() { int n; while (~scanf("%d", &n)) { if (n == 1) { printf("1\n"); continue; } else if (n <= 3) { printf("-1\n"); continue; } f[1] = 2; if (n % 2 == 0) { int x = n - 2; for (int i = 2; i <= n; ++i) { if (i % 2 == 0) f[i] = f[i - 1] + x; else f[i] = f[i - 1] - x; if (i == n / 2) x = 3; else if (i == n / 2 + 1) x = 2; else { if (i < n / 2) x -= 2; else x += 2; } } } else { int x = n - 2; for (int i = 2; i <= n; ++i) { if (i == n / 2 + 1 || i == n / 2 + 2) { f[i] = f[i - 1] - 2; if (i == n / 2 + 1) continue; } else { if (i <= n / 2) { if (i % 2 == 0) f[i] = f[i - 1] + x; else f[i] = f[i - 1] - x; } else { if (i % 2 != 0) f[i] = f[i - 1] + x; else f[i] = f[i - 1] - x; } } if (i <= n / 2) { x -= 2; } else { x += 2; } } } bool flag = 0; for (int i = 1; i <= n; ++i) { if (f[f[i]] != n - i + 1) { flag = 1; break; } } if (flag == 0) { printf("%d", f[1]); for (int i = 2; i <= n; ++i) printf(" %d", f[i]); } else printf("-1"); puts(""); } return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
import java.util.*; import java.io.*; public class Main implements Runnable { public void solve() throws IOException { int N = nextInt(); int[] ans = new int[N]; if((N%4) > 1){ System.out.println(-1); return; } if(N % 4 == 1){ ans[N/2] = N/2; } for(int i = 0; i < N/2; i += 2){ ans[i] = i+1; ans[i+1] = N-1 - i; ans[N - 1 - i] = N - 1 - (i + 1); ans[N - 2 - i] = i; } for(int i = 0; i < ans.length; i++) ans[i]++; print1Int(ans); } //----------------------------------------------------------- public static void main(String[] args) { new Main().run(); } public void print1Int(int[] a){ for(int i = 0; i < a.length; i++) System.out.print(a[i] + " "); System.out.println(); } public void print2Int(int[][] a){ for(int i = 0; i < a.length; i++){ for(int j = 0; j < a[0].length; j++){ System.out.print(a[i][j] + " "); } System.out.println(); } } public void run() { try { in = new BufferedReader(new InputStreamReader(System.in)); tok = null; solve(); in.close(); } catch (IOException e) { System.exit(0); } } public String nextToken() throws IOException { while (tok == null || !tok.hasMoreTokens()) { tok = new StringTokenizer(in.readLine()); } return tok.nextToken(); } public int nextInt() throws IOException { return Integer.parseInt(nextToken()); } public long nextLong() throws IOException { return Long.parseLong(nextToken()); } public double nextDouble() throws IOException { return Double.parseDouble(nextToken()); } BufferedReader in; StringTokenizer tok; }
JAVA
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; int flag[111111]; int main() { int n; cin >> n; if (n % 4 == 3 || n % 4 == 2) { cout << -1 << endl; return 0; } int m = n / 4; for (int i = 1, j = 1; i <= m; i++, j = j + 2) { flag[j] = j + 1; flag[j + 1] = n - j + 1; flag[n - j + 1] = n + 1 - flag[j]; flag[n - j] = n + 1 - flag[j + 1]; } if (n % 4 == 1) { flag[n / 2 + 1] = n / 2 + 1; } for (int i = 1; i <= n; i++) { if (i == n) { cout << flag[i] << endl; } else { cout << flag[i] << " "; } } return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; int res[110000]; int main() { int n; while (cin >> n) { if (n / 2 % 2) { cout << -1 << endl; continue; } res[n / 2] = n / 2; for (int i = 0; i < n / 2; i += 2) { res[i] = i + 1; res[i + 1] = n - i - 1; res[n - i - 1] = n - i - 2; res[n - i - 2] = i; } for (int i = 0; i < n; i++) { cout << res[i] + 1 << ' '; } cout << endl; } return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; int p[1111111]; int main() { int n; int cnt = 1; scanf("%d", &n); if (n % 4 == 2 || n % 4 == 3) { printf("-1\n"); return 0; } if (n == 1) { printf("1\n"); return 0; } int tmp = n / 2; for (int i = 1; i <= tmp; i += 2) { p[i] = i + 1; p[n - i + 1] = n - i; p[i + 1] = n + 1 - i; p[n - i] = i; } if (n % 2 == 1) p[(n + 1) / 2] = (n + 1) / 2; for (int i = 1, _b = n; i <= _b; i++) printf("%d ", p[i]); return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
N = int(raw_input()) if N%4 >= 2: print -1 else: perm = [0 for i in xrange(N)] for i in xrange(0,N/2,2): perm[i] = i+1 perm[i+1] = N-i-1 perm[-i-1] = N-perm[i]-1 perm[-i-2] = i if N%2 == 1: perm[N/2] = N/2 for p in perm: print p+1, print
PYTHON
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
import java.util.Locale; import java.util.Scanner; public class HappyPermutationSolver { private int n; public static void main(String[] args) { HappyPermutationSolver solver = new HappyPermutationSolver(); solver.readData(); int[] solution = solver.solve(); solver.print(solution); } private int gcd(int a, int b) { return b == 0 ? a : gcd(b, a % b); } private int lcm(int a, int b) { return a * b / gcd(a, b); } private void print(int[] values) { if (values.length > 0) { StringBuilder builder = new StringBuilder(); for (int value : values) { builder.append(value); builder.append(" "); } print(builder); } else { print(-1); } } private void print(Object value) { System.out.println(value); } private void print(boolean value) { System.out.println(value ? "YES" : "NO"); } private void print(int value) { System.out.println(value); } private void print(long value) { System.out.println(value); } private void print(double value) { System.out.printf(Locale.ENGLISH, "%.10f", value); } private int[] getDigits(int number) { int[] digits = new int[10]; int index = digits.length - 1; int digitsCount = 0; while (number > 0) { digits[index] = number % 10; number /= 10; index--; digitsCount++; } int[] result = new int[digitsCount]; System.arraycopy(digits, digits.length - digitsCount, result, 0, digitsCount); return result; } private int[] readArray(Scanner scanner, int size) { int[] result = new int[size]; for (int i = 0; i < size; i++) { result[i] = scanner.nextInt(); } return result; } private void readData() { Scanner scanner = new Scanner(System.in); n = scanner.nextInt(); } private int[] solve() { int[] result; int x = n & 3; if (x == 0 || x == 1) { result = new int[n]; if ((n & 1) == 1) { result[n >> 1] = (n >> 1) + 1; } for (int i = 1; i < (n >> 1); i += 2) { result[i - 1] = i + 1; result[i] = n - i + 1; result[n - i] = n - i; result[n - i - 1] = i; } } else { result = new int[0]; } return result; } }
JAVA
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; int main() { int n; cin >> n; if (n % 4 == 2 || n % 4 == 3) { cout << "-1"; return 0; } int p[n + 1]; for (int i = 1; i < n / 2; i += 2) { p[i] = i + 1; p[i + 1] = n - i + 1; p[n - i + 1] = n - i; p[n - i] = i; } if (n % 4 == 1) { p[n / 2 + 1] = n / 2 + 1; } for (int i = 1; i <= n; i++) { cout << p[i] << " "; } return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; int main() { ios::sync_with_stdio(false); cin.tie(0); cout.tie(0); long long n; cin >> n; if (n % 4 >= 2) { puts("-1"); return 0; } vector<long long> p(n); long long k = 1; for (long long i = 0; i < n / 2; i += 2) { p[n - i - 2] = k; p[i] = k + 1; p[n - i - 1] = n - k; p[i + 1] = n - k + 1; k += 2; } if (n % 4 == 1) p[n / 2] = (n + 1) / 2; for (long long i = (0); i < (long long)(p.size()); i++) cout << p[i] << " "; cout << "\n"; ; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
import java.util.Scanner; public class Prob286A { public static void main(String[] Args) { Scanner scan = new Scanner(System.in); int x = scan.nextInt(); if (x % 4 < 2) { int[] arr = new int[x]; int min = 1; int max = x; if (x % 2 == 1) arr[x / 2] = x / 2 + 1; int count = x / 4; while (count-- > 0) { arr[min - 1] = min + 1; arr[min] = max; arr[max - 2] = min; arr[max - 1] = max - 1; min += 2; max -= 2; } for (int i = 0; i < x; i++) System.out.print(arr[i] + " " ); } else System.out.println(-1); } }
JAVA
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
import java.io.PrintWriter; import java.util.Scanner; public class A { int N; int ans[]; private A() { } private void read() { Scanner sc = new Scanner(System.in); N = sc.nextInt(); } private void init() { } private void solve() { ans = new int[N]; for (int i=0; i<N/2; i+=2) { ans[i] = i+2; ans[i+1] = N-i; ans[N-i-1] = N-i-1; ans[N-i-2] = i+1; } if (1 == N % 4) { ans[N/2] = N/2 + 1; } } private void save() { PrintWriter pw = new PrintWriter(System.out); if (2 == N % 4 || 3 == N % 4) { pw.print(-1); } else { for (int i=0; i<N; i++) { if (i > 0) { pw.print(" "); } pw.print(ans[i]); } } pw.close(); } private void run() { read(); init(); solve(); save(); } public static void main(String args[]) { new A().run(); } }
JAVA
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
import java.util.*; public class Main { public static void main(String[] args) { Scanner in = new Scanner(System.in); // get n int n = in.nextInt(); // check parity of (n / 2) if ((n / 2) % 2 == 1) { System.out.println(-1); return; } int[] ary = new int[n + 5]; // check parity of n if (n % 2 == 1) { int m = n + 1; m /= 2; ary[m] = m; } // for for (int i = 1; i <= n / 2; i += 2) { int a = i; int b = i + 1; int A = n + 1 - a; int B = n + 1 - b; ary[a] = B; ary[B] = A; ary[A] = b; ary[b] = a; } StringBuilder sb = new StringBuilder(); for (int i = 1; i <= n; i++) { sb.append(ary[i]); if (i + 1 <= n) sb.append(" "); } System.out.println(sb); } }
JAVA
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
import java.io.*; import java.util.*; import java.math.*; public class Main { public static void main(String[] args) { new Main().run(); } void run() { InputReader in = new InputReader(System.in); PrintWriter out = new PrintWriter(System.out); int n = in.nextInt(); if (n % 4 > 1) { out.println(-1); } else { for (int i = 0; i < n / 2; i += 2) out.print((i + 2) + " " + (n - i) + " "); if (n % 4 == 1) out.print((n / 2 + 1) + " "); for (int i = (n + 1) / 2; i < n; i += 2) out.print((n - i - 1) + " " + (i + 1) + " "); out.println(); } out.close(); } } class InputReader { BufferedReader buff; StringTokenizer tokenizer; InputReader(InputStream stream) { buff = new BufferedReader(new InputStreamReader(stream)); tokenizer = null; } boolean hasNext() { while (tokenizer == null || !tokenizer.hasMoreTokens()) try { tokenizer = new StringTokenizer(buff.readLine()); } catch (Exception e) { return false; } return true; } String next() { if (!hasNext()) throw new RuntimeException(); return tokenizer.nextToken(); } int nextInt() { return Integer.parseInt(next()); } long nextLong() { return Long.parseLong(next()); } }
JAVA
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; int ax[100010]; int main(void) { int n; scanf("%d", &n); if (!(n % 4 == 0 || n % 4 == 1)) { printf("-1\n"); return 0; } for (int i = 1; i <= n / 2; i += 2) { ax[i] = i + 1; ax[i + 1] = n - i + 1; ax[n - i] = i; ax[n - i + 1] = n - i; } if (n % 2 == 1) { ax[n / 2 + 1] = n / 2 + 1; } for (int i = 1; i <= n; i++) { printf("%d ", ax[i]); } return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; vector<long long> v[301], vv, v1; long long a, b, c[1234567], c1[1234][1234], e, i, j, n, x, y, l, r, k; string s, s1; long long used[301]; long long ans; bool ok[123]; int main() { cin >> n; if (n / 2 % 2 == 1) { cout << -1; exit(0); } a = 2; for (int i = 1; i <= n / 2; i += 2) { c[i] = i + 1; c[n - i + 1] = (n + 1) - (i + 1); c[n - i] = i; c[i + 1] = n + 1 - i; } if (n % 2 == 1) c[n / 2 + 1] = n / 2 + 1; for (long long i = 1; i <= n; i++) cout << c[i] << " "; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; const int maxn = 1e5 + 5; int p[maxn]; int n; int main() { while (~scanf("%d", &n)) { if (n == 1) { printf("1\n"); continue; } if (n <= 3) { printf("-1\n"); continue; } memset(p, 0, sizeof(p)); ; if (n & 1) { if ((n - 1) % 4 != 0) { printf("-1\n"); continue; } p[(n + 1) / 2] = (n + 1) / 2; } else { if (n % 4 != 0) { printf("-1\n"); continue; } } for (int i = 1; i <= n / 2; i += 2) { p[i] = i + 1; p[i + 1] = n - i + 1; p[n - i + 1] = n - i; p[n - i] = i; } for (int i = 1; i <= n; i++) printf("%d ", p[i]); printf("\n"); } return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; int main() { int n; cin >> n; if (n % 4 && (n - 1) % 4) { cout << -1 << endl; return 0; } int ara[n + 1], i; for (i = 1; i <= n / 2; i += 2) { ara[i] = i + 1; } for (i = 2; i <= n / 2; i += 2) { ara[i] = n - i + 2; } for (i = n; i > (n + 1) / 2; i -= 2) { ara[i] = i - 1; } for (i = n - 1; i > (n + 1) / 2; i -= 2) { ara[i] = n - i; } if (n % 2) ara[(n + 1) / 2] = (n + 1) / 2; for (i = 1; i <= n; i++) cout << ara[i] << " "; cout << endl; return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
import java.io.BufferedWriter; import java.util.InputMismatchException; import java.io.InputStream; import java.util.NoSuchElementException; import java.io.OutputStreamWriter; import java.math.BigInteger; import java.io.OutputStream; import java.io.PrintWriter; import java.io.Writer; import java.io.IOException; /** * Built using CHelper plug-in * Actual solution is at the top * @author Nguyen Trung Hieu - [email protected] */ public class Main { public static void main(String[] args) { InputStream inputStream = System.in; OutputStream outputStream = System.out; InputReader in = new InputReader(inputStream); OutputWriter out = new OutputWriter(outputStream); TaskA solver = new TaskA(); solver.solve(1, in, out); out.close(); } } class TaskA { public void solve(int testNumber, InputReader in, OutputWriter out) { int count = in.readInt(); if (count % 4 >= 2) { out.printLine(-1); return; } if (count == 1) { out.printLine(1); return; } if (count % 4 == 0) { int left = 2; int right = count; while (left <= right) { out.print(left + " " + right + " "); left += 2; right -= 2; } left = (count - 2) / 2; right = (count + 2) / 2; while (left > 0) { out.print(left + " " + right + " "); left -= 2; right += 2; } } else { int left = 2; int right = count; while (left <= right) { out.print(left + " " + right + " "); left += 2; right -= 2; } out.print((count + 1) / 2 + " "); left = (count - 3) / 2; right = (count + 3) / 2; while (left > 0) { out.print(left + " " + right + " "); left -= 2; right += 2; } } } } class InputReader { private InputStream stream; private byte[] buf = new byte[1024]; private int curChar; private int numChars; private SpaceCharFilter filter; public InputReader(InputStream stream) { this.stream = stream; } public int read() { if (numChars == -1) throw new InputMismatchException(); if (curChar >= numChars) { curChar = 0; try { numChars = stream.read(buf); } catch (IOException e) { throw new InputMismatchException(); } if (numChars <= 0) return -1; } return buf[curChar++]; } public int readInt() { int c = read(); while (isSpaceChar(c)) c = read(); int sgn = 1; if (c == '-') { sgn = -1; c = read(); } int res = 0; do { if (c < '0' || c > '9') throw new InputMismatchException(); res *= 10; res += c - '0'; c = read(); } while (!isSpaceChar(c)); return res * sgn; } public boolean isSpaceChar(int c) { if (filter != null) return filter.isSpaceChar(c); return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1; } public interface SpaceCharFilter { public boolean isSpaceChar(int ch); } } class OutputWriter { private final PrintWriter writer; public OutputWriter(OutputStream outputStream) { writer = new PrintWriter(new BufferedWriter(new OutputStreamWriter(outputStream))); } public void print(Object...objects) { for (int i = 0; i < objects.length; i++) { if (i != 0) writer.print(' '); writer.print(objects[i]); } } public void printLine(Object...objects) { print(objects); writer.println(); } public void close() { writer.close(); } }
JAVA
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> const bool debug = false; using namespace std; long long powmod(long long a, long long b, long long MOD) { long long res = 1; a %= MOD; for (; b; b >>= 1) { if (b & 1) res = res * a % MOD; a = a * a % MOD; } return res; } void buginfo(const char* f, ...) { if (!debug) return; va_list al; va_start(al, f); vprintf(f, al); va_end(al); } const int maxn = 1e5 + 10; int n, a[maxn]; int main() { scanf("%d", &n); if (n % 4 == 2 || n % 4 == 3) { printf("-1\n"); return 0; } int p = 1, q = n; while (p < q) { a[p] = p + 1; a[p + 1] = q; a[q] = q - 1; a[q - 1] = p; p += 2, q -= 2; } if (p == q) a[p] = p; for (int i = 1; i < n + 1; ++i) printf("%d ", a[i]); printf("\n"); return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; template <class T> inline void checkmin(T& a, const T& b) { if (a > b) a = b; }; template <class T> inline void checkmax(T& a, const T& b) { if (a < b) a = b; }; int main() { for (int n; cin >> n;) { vector<int> ans(n + 1); if (n % 4 == 2 || n % 4 == 3) { puts("-1"); continue; } int left = 1, right = n; while (right - left + 1 >= 4) { ans[left] = right - 1; ans[left + 1] = left; ans[right - 1] = right; ans[right] = left + 1; left += 2; right -= 2; } if (left == right) { ans[left] = right; } for (int i = 1; i <= n; ++i) cout << ans[i] << " "; cout << endl; } }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
import java.io.*; import java.util.*; import java.math.*; import java.awt.geom.*; import static java.lang.Math.*; public class Solution implements Runnable { int n; int p []; boolean used[]; int count = 0; void doIt (int k) { if (count > 0) return; if (k == n + 1) { boolean good = true; for (int i = 1; i <= n; i++) { if (p[p[i]] != n - i + 1) { good = false; } } if (good) { count++; for (int i = 1; i <= n; i++) { out.print(p[i]+" "); } out.println(); } } else { for (int i = 1; i <= n; i++) { if (!used[i]) { used[i] = true; p[k] = i; doIt (k + 1); used[i] = false; } } } } public void solve() throws Throwable { n = sc.nextInt(); if (n == 1) { out.println(1); return; } else if (n <= 3) { out.println(-1); return; } p = new int [n + 1]; used = new boolean [n + 1]; if (n % 4 == 0 || (n - 1) % 4 == 0) { int l = 1; int r = n; while (l < r) { p[l] = l + 1; p[l + 1] = n - l + 1; p[r] = n - l; p[r - 1] = l; l += 2; r -= 2; } if (l == r) { p[l] = n / 2 + 1; } } else { out.println(-1); return; } for (int i = 1; i <= n; i++) { out.print((p[i])+" "); } } BufferedReader in; PrintWriter out; FastScanner sc; static Throwable uncaught; @Override public void run() { try { in = new BufferedReader(new InputStreamReader(System.in)); out = new PrintWriter(System.out); sc = new FastScanner(in); solve(); } catch (Throwable t) { Solution.uncaught = t; } finally { out.close(); } } public static void main(String[] args) throws Throwable { Thread t = new Thread(null, new Solution(), "", (1 << 26)); t.start(); t.join(); if (uncaught != null) { throw uncaught; } } } class FastScanner { BufferedReader reader; StringTokenizer strTok; public FastScanner(BufferedReader reader) { this.reader = reader; } public String nextToken() throws IOException { while (strTok == null || !strTok.hasMoreTokens()) { strTok = new StringTokenizer(reader.readLine().trim()); } return strTok.nextToken(); } public int nextInt() throws IOException { return Integer.parseInt(nextToken()); } public long nextLong() throws IOException { return Long.parseLong(nextToken()); } public double nextDouble() throws IOException { return Double.parseDouble(nextToken()); } }
JAVA
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; namespace Flandre_Scarlet { int n; void Input() { cin >> n; } int a[155555]; void Soviet() { memset(a, 0, sizeof(a)); if (n % 4 == 0) { for (int i = 1; i <= n; ++i) { if (!a[i]) { a[i] = i + 1; a[i + 1] = n - i + 1; a[n - i + 1] = n - i; a[n - i] = i; } } for (int i = 1; i <= n; ++i) { printf("%d ", a[i]); } putchar('\n'); } else if (n % 4 == 1) { a[n / 2 + 1] = n / 2 + 1; for (int i = 1; i <= n / 2; ++i) { if (!a[i]) { a[i] = i + 1; a[i + 1] = n - i + 1; a[n - i + 1] = n - i; a[n - i] = i; } } for (int i = 1; i <= n; ++i) { printf("%d ", a[i]); } putchar('\n'); } else { puts("-1"); } } void IsMyWife() { Input(); Soviet(); } } // namespace Flandre_Scarlet int main() { Flandre_Scarlet::IsMyWife(); getchar(); getchar(); return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; int f[100010]; int N; bool dfs(int l, int r, int k) { if (r - l + 1 >= 4) { f[l] = 2 + k * 2; f[l + 1] = N - k * 2; f[r] = N - 1 - k * 2; f[r - 1] = 1 + k * 2; return dfs(l + 2, r - 2, k + 1); } else if (r - l + 1 == 1) { f[r] = r; return true; } else if (r < l) return true; return false; } int main() { scanf("%d", &N); if (!dfs(1, N, 0)) { printf("-1\n"); return 0; } for (int(i) = 1; (i) < (N + 1); (i)++) { if (i != 1) putchar(' '); printf("%d", f[i]); } putchar('\n'); return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; int main() { int n; cin >> n; if (n == 1) { cout << 1; return 0; } if (n % 4 == 3 || n % 4 == 2) { cout << -1 << endl; return 0; } int a[n + 1]; int i = 1, j = n, l = 1, r = n; while (i < j) { a[i] = l + 1; a[j] = r - 1; a[i + 1] = r; a[j - 1] = l; l += 2; r -= 2; i += 2; j -= 2; } if (i == j) a[i] = l; for (int i = 1; i <= n; i++) cout << a[i] << " "; return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; int a[100002]; int main() { int n; cin >> n; if (n % 4 > 1) return cout << -1, 0; if (n % 4 == 1) a[(n - 1) / 2 + 1] = (n - 1) / 2 + 1; int e = n / 2; for (int i = 1; i < e; i += 2) { a[i] = i + 1; a[i + 1] = n - i + 1; a[n - i + 1] = n - i; a[n - i] = i; } for (int i = 1; i <= n; i++) cout << a[i] << ' '; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; int a[100005], n, p, x, k; bool test() { for (int i = 1; i <= n; i++) if (a[a[i]] != n - i + 1) return 0; return 1; } int main() { scanf("%d", &n); k = ceil(n / 2.0); int x = 1, p = 2; while (x <= k) { a[x] = p; p += 2; x += 2; } x = n; p = n - 1; while (x > k) { a[x] = p; p -= 2; x -= 2; } if (n % 2) a[n / 2 + 1] = n / 2 + 1; for (int i = 1; i <= n; i++) if (a[i]) a[a[i]] = n - i + 1; if (test()) { printf("%d", a[1]); for (int i = 2; i <= n; i++) printf(" %d", a[i]); printf("\n"); } else printf("-1\n"); return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; int n; int main() { cin >> n; if (n % 4 > 1) { cout << "-1\n"; return 0; } for (int i = 1; i <= n / 2; i++) { if (i % 2) cout << i + 1 << ' '; else cout << (n - i + 2) << ' '; } int m = n / 2; if (n % 4 == 1) { cout << m + 1; if (m + 1 < n) cout << ' '; m++; } for (int i = m + 1; i < n; i++) { if ((i - m) % 2) cout << n - i << ' '; else cout << i - 1 << ' '; } if (m + 1 < n) cout << (n - 1); cout << endl; return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
import java.io.*; import java.math.BigInteger; import java.util.*; public class A { private static final int mod = (int)1e9+7; boolean ok (final int[] xs) { for(int i = 0; i < xs.length; i++) { if(xs[xs[i]] != xs.length - 1 - i) { return false; } } return true; } int[] xs; void check(int a, int b) { xs[a] = b; for(int i = 0; i < xs.length; i++) { final int c = xs.length - 1 - xs[a]; // System.err.println("2: " + Arrays.toString(xs) + " " + a + " " + b + " " + c); if(xs[c] == a) break; xs[c] = a; a = c; } // System.err.println(Arrays.toString(xs)); } public void run() throws IOException { final int n = IOFast.nextInt(); xs = new int[n]; Arrays.fill(xs, -1); if(n == 1) { IOFast.out.println(1); return; } for(int i = n - 2, j = 0; i >= 0; i -= 2, j += 2) if(xs[i] == -1) { check(i, j); } if(n % 2 == 1) xs[n/2] = n/2; if(ok(xs)) { for(int j = 0; j < xs.length; j++) { IOFast.out.print(++xs[j] + (j == xs.length-1?"\n":" ")); } return; } IOFast.out.println(-1); /* LOOP: for(int i = 1; i <= 10; i++) { IOFast.out.println("check: " + i); final int[] xs = new int[i]; for(int j = 0; j < xs.length; j++) { xs[j] = j; } do { if(ok(xs)){ for(int j = 0; j < xs.length; j++) { IOFast.out.print(xs[j] + " "); } IOFast.out.println(); continue LOOP; } } while(Permutation.nextPermutation(xs)); IOFast.out.println("NOT FOUND"); } */ } static public class Permutation { private static final void swap(int[] xs, int i, int j) { final int t = xs[j]; xs[j] = xs[i]; xs[i] = t; } private static final boolean nextPermutation(final int[] xs) { for(int i = xs.length - 1; i > 0; i--) { if(xs[i - 1] > xs[i]) { continue; } for(int j = i, k = xs.length - 1; j < k; j++, k--) { swap(xs, j, k); } for(int j = i; j < xs.length; j++) if(xs[j] > xs[i - 1]) { swap(xs, j, i - 1); break; } return true; } return false; } } public static void main(String[] args) throws IOException { // IOFast.setFileIO("input.txt", "output.txt"); new A().run(); IOFast.out.flush(); } static public class IOFast { private static BufferedReader in = new BufferedReader(new InputStreamReader(System.in)); private static PrintWriter out = new PrintWriter(System.out); static void setFileIO(String ins, String outs) throws IOException { try { in = new BufferedReader(new FileReader(ins)); out = new PrintWriter(new FileWriter(outs)); } catch(IOException e) { System.err.println(e); throw e; } } // private static final int BUFFER_SIZE = 50 * 200000; private static int pos, readLen; private static final char[] buffer = new char[1024 * 8]; private static final StringBuilder buf = new StringBuilder(); private static boolean[] isDigit = new boolean[256]; private static boolean[] isSpace = new boolean[256]; static { for(int i = 0; i < 10; i++) { isDigit['0' + i] = true; } isDigit['-'] = true; isSpace[' '] = isSpace['\r'] = isSpace['\n'] = isSpace['\t'] = true; } static boolean endInput; private static int read() throws IOException { if(readLen == -1) { return -1; } if(pos >= readLen) { readLen = in.read(buffer); pos = 0; if(readLen <= 0) { return -1; } } return buffer[pos++]; } private static int nextInt() throws IOException { boolean plus = false; int ret = 0; while(true) { final int c = read(); if(c == -1) { endInput = true; return Integer.MIN_VALUE; } if(isDigit[c]) { if(c != '-') { plus = true; ret = c - '0'; } break; } } while(true) { final int c = read(); if(c == -1 || !isDigit[c]) { break; } ret = ret * 10 + c - '0'; } return plus ? ret : -ret; } private static long nextLong() throws IOException { boolean plus = false; long ret = 0; while(true) { final int c = read(); if(c == -1) { endInput = true; return Integer.MIN_VALUE; } if(isDigit[c]) { if(c != '-') { plus = true; ret = c - '0'; } break; } } while(true) { final int c = read(); if(c == -1 || !isDigit[c]) { break; } ret = ret * 10 + c - '0'; } return plus ? ret : -ret; } private static char nextChar() throws IOException { while(true) { final int c = read(); if(c == -1) { endInput = true; return '\0'; } if(!isSpace[c]) { return (char)c; } } } private static String next() throws IOException { buf.setLength(0); while(true) { final int c = read(); if(c == -1) { endInput = true; return "-1"; } if(!isSpace[c]) { buf.append((char)c); break; } } while(true) { final int c = read(); if(c == -1 || isSpace[c]) { break; } buf.append((char)c); } return buf.toString(); } private static double nextDouble() throws IOException { return Double.parseDouble(next()); } } }
JAVA
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> #pragma comment(linker, "/STACK:666000000") using namespace std; const int inf = (1 << 30) - 1; const long double eps = 1e-9; const long double pi = fabs(atan2(0.0, -1.0)); void ML() { int *ass; for (;;) { ass = new int[2500000]; for (int i = 0; i < 2500000; i++) ass[i] = rand(); } } int n; int a[100500]; void LoAd() { cin >> n; } void SoLvE() { if (1 == n) { puts("1"); return; } if (2 == n || 3 == n) { puts("-1"); return; } int lt = 0; int rt = n - 1; while (lt <= rt) { if (0 == rt - lt) { a[lt] = lt; break; } else if (1 == rt - lt || 2 == rt - lt) { puts("-1"); return; } else { a[rt - 1] = lt; a[rt] = rt - 1; a[lt] = lt + 1; a[lt + 1] = rt; lt += 2; rt -= 2; } } for (int i = 0; i < n; i++) printf("%d ", a[i] + 1); puts(""); } int main() { srand((int)time(NULL)); { LoAd(); SoLvE(); } return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
import java.io.*; import java.math.*; import java.util.*; public class Solution { public void run() { try { int n = reader.nextInt(); if (n % 4 >= 2) { writer.println(-1); } else { int[] p = new int[n]; for (int i = 0; i < n; ++ i) { p[i] = i; } for (int i = 0; i + 1 < n - i - 2; i += 2) { p[i] = n - i - 2; p[n - i - 2] = p[n - i - 1]; p[n - i - 1] = p[i + 1]; p[i + 1] = i; } for (int i = 0; i < n; ++ i) { writer.print(String.format("%d%c", p[i] + 1, i == n - 1 ? '\n' : ' ')); } } } catch (IOException ex) { } writer.close(); } InputReader reader; PrintWriter writer; Solution() { reader = new InputReader(); writer = new PrintWriter(System.out); } public static void main(String[] args) { new Solution().run(); } } class InputReader { BufferedReader reader; StringTokenizer tokenizer; InputReader() { reader = new BufferedReader(new InputStreamReader(System.in)); tokenizer = new StringTokenizer(""); } String next() throws IOException { while (!tokenizer.hasMoreTokens()) { tokenizer = new StringTokenizer(reader.readLine()); } return tokenizer.nextToken(); } Integer nextInt() throws IOException { return Integer.parseInt(next()); } }
JAVA
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; int seq[111111]; int main(void) { int n = 0; scanf("%d", &n); if (n % 4 > 1) puts("-1"); else { for (int i = 0; i < n / 4; i++) { int t = i * 2 + 1; int l = n + 1 - t; seq[t] = t + 1; seq[t + 1] = l; seq[l] = l - 1; seq[l - 1] = t; } for (int i = 1; i <= n; i++) if (seq[i] == 0) seq[i] = i; for (int i = 1; i <= n; i++) printf("%d ", seq[i]); puts(""); bool okay = true; for (int i = 1; i <= n; i++) if (seq[seq[i]] != n - i + 1) okay = false; } while (getchar() != EOF) ; return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; int n; int a[100010]; int main() { cin >> n; if (n % 4 > 1) { cout << -1; return 0; } for (int i = 1; i < n / 2; i += 2) { a[i] = i + 1; a[i + 1] = n - i + 1; a[n - i + 1] = n - i; a[n - i] = i; } if (n % 2 == 1) a[n / 2 + 1] = n / 2 + 1; for (int i = 1; i <= n; i++) cout << a[i] << ' '; return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; int main() { int arr[100009] = {0}; bool vis[100009] = {0}; set<int> st; bool f = 1; int n = 0; cin >> n; if (n == 1) { cout << n; return 0; } if (n <= 3) { cout << -1; return 0; } for (int i = 1; i <= n; i++) st.insert(i); while (st.size()) { int i = *st.begin(); st.erase(i); int v = vis[i + 1] ? i : i + 1; while (!vis[v]) { vis[v] = 1; int v2 = n - i + 1; arr[i] = v; i = v; v = v2; st.erase(i); } } for (int i = 1; i <= n; i++) f &= vis[i]; if (!f) cout << -1; else for (int i = 1; i <= n; i++) cout << arr[i] << " "; return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; FILE *f, *g; int v[100100]; int i, j, q; int n; int main() { scanf("%d", &n); if (n % 4 == 2 || n % 4 == 3) { printf("-1"); return 0; } for (i = 1, j = n; i <= (n / 4) * 2; i += 2, j -= 2) { v[i] = i + 1; v[i + 1] = j; v[j - 1] = i; v[j] = j - 1; } if (n % 4 == 1) { v[i] = i; } for (i = 1; i <= n; i++) printf("%d ", v[i]); return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
//package codeforces; import java.io.BufferedReader; import java.io.BufferedWriter; import java.io.Closeable; import java.io.FileReader; import java.io.FileWriter; import java.io.IOException; import java.io.InputStreamReader; import java.io.OutputStreamWriter; import java.io.PrintWriter; import java.math.BigInteger; import java.util.ArrayList; import java.util.Arrays; import java.util.Collection; import java.util.Collections; import java.util.Comparator; import java.util.HashMap; import java.util.HashSet; import java.util.Iterator; import java.util.LinkedList; import java.util.List; import java.util.ListIterator; import java.util.Map; import java.util.PriorityQueue; import java.util.Queue; import java.util.Set; import java.util.StringTokenizer; import java.util.TreeSet; public class A implements Closeable { BufferedReader reader = new BufferedReader(new InputStreamReader(System.in)); PrintWriter writer = new PrintWriter(new BufferedWriter(new OutputStreamWriter(System.out))); A() throws IOException { // reader = new BufferedReader(new FileReader("input.txt")); // writer = new PrintWriter(new FileWriter("output.txt")); } StringTokenizer stringTokenizer; String next() throws IOException { while (stringTokenizer == null || !stringTokenizer.hasMoreTokens()) { stringTokenizer = new StringTokenizer(reader.readLine()); } return stringTokenizer.nextToken(); } int nextInt() throws IOException { return Integer.parseInt(next()); } long nextLong() throws IOException { return Long.parseLong(next()); } private int MOD = 1000 * 1000 * 1000 + 7; int sum(int a, int b) { a += b; return a >= MOD ? a - MOD : a; } int product(int a, int b) { return (int) (1l * a * b % MOD); } int pow(int x, int k) { int result = 1; while (k > 0) { if (k % 2 == 1) { result = product(result, x); } x = product(x, x); k /= 2; } return result; } int inv(int x) { return pow(x, MOD - 2); } void solve() throws IOException { int n = nextInt(); if(n % 4 != 0 && n % 4 != 1) { writer.println(-1); return; } int[] p = new int[n]; for(int i = 1; i < n / 2; i += 2) { int x = i, y = n - x + 1, u = i + 1, v = n - u + 1; //x -> u -> y -> v p[x - 1] = u; p[u - 1] = y; p[y - 1] = v; p[v - 1] = x; } if(n % 2 == 1) { p[n / 2] = n / 2 + 1; } for (int x : p) { writer.print(x + " "); } } public static void main(String[] args) throws IOException { try (A a = new A()) { a.solve(); } } @Override public void close() throws IOException { reader.close(); writer.close(); } }
JAVA
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; int n; int a[100005]; int used[10005]; bool check(int i) { if (a[i] == -1) return true; if (a[a[i] - 1] == -1) { a[a[i] - 1] = n - i; used[n - i] = true; } else return a[a[i] - 1] == n - i; return check(a[i] - 1); } bool checkans() { for (int i = 0; i < n; ++i) { if (a[i] != -1) { if (!check(i)) return false; } else { for (int j = 1; j <= n; ++j) { if (used[j]) continue; used[j] = true; a[i] = j; if (check(i)) break; a[i] = -1; used[j] = false; } } } return true; } int main() { cin >> n; if (n == 1 || ((n - (n % 2)) % 4 == 0)) { for (int i = 2; i <= n / 2; i += 2) { printf("%d %d ", i, n - i + 2); } if (n % 2) printf("%d ", n / 2 + 1); for (int i = n / 2 - 1; i >= 1; i -= 2) { printf("%d %d ", i, n - i); } } else printf("-1"); return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; set<int> st; int ans[100007]; int main() { int n; cin >> n; if (n % 4 == 2 || n % 4 == 3) { cout << "-1" << endl; return 0; } for (int i = 1; i <= n; i++) st.insert(i); if (n % 4 == 1) { int idx = (n + 1) / 2; st.erase(idx); ans[idx] = idx; } while (!st.empty()) { int num1 = *(st.begin()); set<int>::iterator it; it = ++st.begin(); int num2 = *it; int num3 = n - num1 + 1; int num4 = n - num2 + 1; ans[num1] = num2; ans[num2] = num3; ans[num3] = num4; ans[num4] = num1; st.erase(num1); st.erase(num2); st.erase(num3); st.erase(num4); } for (int i = 1; i <= n; i++) cout << ans[i] << " "; return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; const double PI = 3.1415926535; int n; int main() { cin >> n; if (n % 4 > 1) cout << -1; else { int x = n / 4; for (int i = 0; i < x; ++i) printf("%d %d ", 2 + i * 2, n - i * 2); if (n % 4 == 1) printf("%d ", n / 2 + 1); for (int i = x - 1; i >= 0; --i) printf("%d %d ", 1 + i * 2, n - 1 - i * 2); } return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; int main() { int n; int p[100005], parent[100005]; scanf("%d", &n); if (n % 4 > 1) { printf("-1\n"); return 0; } memset(parent, 0, sizeof(parent)); for (int i = 1; i <= n / 2; i += 2) { p[i] = 1 + i; p[i + 1] = n - i + 1; p[n - i + 1] = n - i; p[n - i] = i; } if (n % 4 == 1) p[n / 2 + 1] = n / 2 + 1; for (int i = 1; i < n; ++i) { printf("%d ", p[i]); } printf("%d\n", p[n]); return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; int main() { ios::sync_with_stdio(0); cin.tie(0); int n; cin >> n; if (n % 4 > 1) { cout << "-1\n"; return 0; } int p[n]; if (n % 4 == 1) { p[n / 2] = (n + 1) / 2; } for (int i = 0, j = n - 2; i < n / 2; i += 2, j -= 2) { if (i == 0) { p[0] = 2; p[1] = n; } else { p[i] = p[i - 2] + 2; p[i + 1] = p[i - 1] - 2; } p[j] = p[i] - 1; p[j + 1] = p[i + 1] - 1; } for (int i : p) cout << i << " "; cout << endl; return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
import java.io.*; import java.util.*; public class Contest176 { public static void main(String[] args) throws IOException { new Contest176().run(); } public void solve() throws IOException { int n = nextInt(); int rem = n % 4; if(rem == 2 || rem == 3) { out.println(-1); return; } int res[] = new int[n + 1]; int map1[] = new int[5]; final int p[] = {0, 3, 1, 4, 2}; for(int i = 1, stop = n / 2 + 1; i < stop; i += 2) { map1[1] = i; map1[2] = i + 1; map1[3] = n - i; map1[4] = n - i + 1; for(int j = 1; j <= 4; ++j) { int num = map1[j]; int prepos = p[j]; int finpos = map1[prepos]; res[finpos] = num; } } if(n % 2 == 1) res[n / 2 + 1] = n / 2 + 1; for(int i = 1; i <= n; ++i) { out.print(res[i]); out.print(' '); } } BufferedReader br; StringTokenizer in; PrintWriter out; String nextToken() throws IOException { while( in == null || !in.hasMoreTokens() ) { in = new StringTokenizer(br.readLine()); } return in.nextToken(); } public int nextInt() throws IOException { return Integer.parseInt(nextToken()); } public long nextLong() throws IOException { return Long.parseLong(nextToken()); } public double nextDouble() throws IOException { return Double.parseDouble(nextToken()); } void run() throws IOException { boolean oj = System.getProperty( "ONLINE_JUDGE" ) != null; Reader reader = new InputStreamReader( oj ? System.in : new FileInputStream("input.txt")); Writer writer = new OutputStreamWriter( oj ? System.out : new FileOutputStream("output.txt")); br = new BufferedReader(reader); out = new PrintWriter(writer); solve(); out.close(); } }
JAVA
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#!/usr/bin/python import sys def read_obj(cls): return cls(sys.stdin.readline().strip()) def read_obj_list(cls): return map(cls, sys.stdin.readline().strip().split()) def solve(): n = read_obj(int) if n % 4 in [2, 3]: print -1 return res = [0 for i in xrange(n + 1)] for i in xrange(1, n / 2 + 1, 2): res[i] = i + 1 res[i + 1] = n - i + 1 res[n - i + 1] = n - i res[n - i] = i if n % 4: res[(n + 1) / 2] = n - (n + 1) / 2 + 1 for i in res[1:]: print i, print if __name__ == "__main__": solve()
PYTHON
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; const int INF = 1 << 30; const double EPS = 1e-7; const int MAX = 100005; int p[MAX]; int main() { ios::sync_with_stdio(false); int n; cin >> n; if (n % 4 > 1) cout << -1 << endl; else { for (int i = 1; i <= n / 2; i += 2) { p[i] = i + 1; p[i + 1] = n - i + 1; p[n - i + 1] = n - i; p[n - i] = i; } if (n % 4 == 1) p[n / 2 + 1] = n / 2 + 1; for (int i = 1; i <= n; i++) cout << p[i] << " "; cout << endl; } return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; int main() { int n; scanf("%d", &n); if (n % 4 == 0 || n % 4 == 1) { if (n % 4 == 0) { for (int i = 1; i <= n / 2; i += 2) { printf("%d ", i + 1); printf("%d ", (n - i + 1)); } for (int i = n / 2 + 1; i <= n; i += 2) { printf("%d ", (n - (i + 1) + 1)); printf("%d ", i); } } else { for (int i = 1; i <= n / 2; i += 2) { printf("%d ", i + 1); printf("%d ", (n - i + 1)); } printf("%d ", n / 2 + 1); for (int i = n / 2 + 2; i <= n; i += 2) { printf("%d ", (n - (i + 1) + 1)); printf("%d ", i); } } } else puts("-1"); }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
import java.io.*; import java.math.*; import java.util.*; import java.util.stream.*; import java.lang.management.*; import static java.lang.Math.*; @SuppressWarnings("unchecked") public class P0286A { public void run() throws Exception { int n = nextInt(), n_2 = n / 2; if (n == 1) { println(1); return; } else if (((n & 0b11) != 0) && (((n - 1) & 0b11) != 0)) { println(-1); return; } StringBuilder ans = new StringBuilder(); for (int i = 2, j = n; i <= n_2; ans.append(i).append(' ').append(j).append(' '), i += 2, j -= 2); if ((n & 1) == 0) { for (int i = n / 2 - 1, j = i + 2; j < n; ans.append(i).append(' ').append(j).append(' '), i -= 2, j += 2); } else { ans.append(n / 2 + 1).append(' '); for (int i = n / 2 - 1, j = (n + 1) / 2 + 1; j < n; ans.append(i).append(' ').append(j).append(' '), i -= 2, j += 2); } println(ans); } public static void main(String... args) throws Exception { br = new BufferedReader(new InputStreamReader(System.in)); pw = new PrintWriter(new BufferedOutputStream(System.out)); new P0286A().run(); br.close(); pw.close(); System.err.println("\n[Time : " + (System.currentTimeMillis() - startTime) + " ms]"); long gct = 0, gcc = 0; for (GarbageCollectorMXBean garbageCollectorMXBean : ManagementFactory.getGarbageCollectorMXBeans()) { gct += garbageCollectorMXBean.getCollectionTime(); gcc += garbageCollectorMXBean.getCollectionCount(); } System.err.println("[GC time : " + gct + " ms, count = " + gcc + "]"); System.err.println("[JIT time : " + ManagementFactory.getCompilationMXBean().getTotalCompilationTime() + " ms]"); } static long startTime = System.currentTimeMillis(); static BufferedReader br; static PrintWriter pw; StringTokenizer stok; String nextToken() throws IOException { while (stok == null || !stok.hasMoreTokens()) { String s = br.readLine(); if (s == null) { return null; } stok = new StringTokenizer(s); } return stok.nextToken(); } void print(byte b) { print("" + b); } void print(int i) { print("" + i); } void print(long l) { print("" + l); } void print(double d) { print("" + d); } void print(char c) { print("" + c); } void print(Object o) { if (o instanceof int[]) { print(Arrays.toString((int [])o)); } else if (o instanceof long[]) { print(Arrays.toString((long [])o)); } else if (o instanceof char[]) { print(Arrays.toString((char [])o)); } else if (o instanceof byte[]) { print(Arrays.toString((byte [])o)); } else if (o instanceof short[]) { print(Arrays.toString((short [])o)); } else if (o instanceof boolean[]) { print(Arrays.toString((boolean [])o)); } else if (o instanceof float[]) { print(Arrays.toString((float [])o)); } else if (o instanceof double[]) { print(Arrays.toString((double [])o)); } else if (o instanceof Object[]) { print(Arrays.toString((Object [])o)); } else { print("" + o); } } void printsp(int [] a) { for (int i = 0, n = a.length; i < n; print(a[i] + " "), i++); } void printsp(long [] a) { for (int i = 0, n = a.length; i < n; print(a[i] + " "), i++); } void print(String s) { pw.print(s); } void println() { println(""); } void println(byte b) { println("" + b); } void println(int i) { println("" + i); } void println(long l) { println("" + l); } void println(double d) { println("" + d); } void println(char c) { println("" + c); } void println(Object o) { print(o); println(); } void println(String s) { pw.println(s); } int nextInt() throws IOException { return Integer.parseInt(nextToken()); } long nextLong() throws IOException { return Long.parseLong(nextToken()); } double nextDouble() throws IOException { return Double.parseDouble(nextToken()); } char nextChar() throws IOException { return (char) (br.read()); } String next() throws IOException { return nextToken(); } String nextLine() throws IOException { return br.readLine(); } int [] readInt(int size) throws IOException { int [] array = new int [size]; for (int i = 0; i < size; i++) { array[i] = nextInt(); } return array; } long [] readLong(int size) throws IOException { long [] array = new long [size]; for (int i = 0; i < size; i++) { array[i] = nextLong(); } return array; } double [] readDouble(int size) throws IOException { double [] array = new double [size]; for (int i = 0; i < size; i++) { array[i] = nextDouble(); } return array; } String [] readLines(int size) throws IOException { String [] array = new String [size]; for (int i = 0; i < size; i++) { array[i] = nextLine(); } return array; } int gcd(int a, int b) { if (a == 0) return Math.abs(b); if (b == 0) return Math.abs(a); a = Math.abs(a); b = Math.abs(b); int az = Integer.numberOfTrailingZeros(a), bz = Integer.numberOfTrailingZeros(b); a >>>= az; b >>>= bz; while (a != b) { if (a > b) { a -= b; a >>>= Integer.numberOfTrailingZeros(a); } else { b -= a; b >>>= Integer.numberOfTrailingZeros(b); } } return (a << Math.min(az, bz)); } long gcd(long a, long b) { if (a == 0) return Math.abs(b); if (b == 0) return Math.abs(a); a = Math.abs(a); b = Math.abs(b); int az = Long.numberOfTrailingZeros(a), bz = Long.numberOfTrailingZeros(b); a >>>= az; b >>>= bz; while (a != b) { if (a > b) { a -= b; a >>>= Long.numberOfTrailingZeros(a); } else { b -= a; b >>>= Long.numberOfTrailingZeros(b); } } return (a << Math.min(az, bz)); } boolean isPrime(int v) { if (v <= 1) { return false; } if (v <= 3) { return true; } if (((v & 1) == 0) || ((v % 3) == 0)) { return false; } for (int m = 5, n = (int)sqrt(v); m <= n; m += 6) { if (((v % m) == 0) || ((v % (m + 2)) == 0)) { return false; } } return true; } int [] rshuffle(int [] a) { // RANDOM shuffle Random r = new Random(); for (int i = a.length - 1, j, t; i >= 0; j = r.nextInt(a.length), t = a[i], a[i] = a[j], a[j] = t, i--); return a; } int [] qshuffle(int [] a) { // QUICK shuffle int m = new Random().nextInt(10) + 2; for (int i = 0, n = a.length, j = m % n, t; i < n; t = a[i], a[i] = a[j], a[j] = t, i++, j = (i * m) % n); return a; } long [] shuffle(long [] a) { Random r = new Random(); for (int i = a.length - 1; i >= 0; i--) { int j = r.nextInt(a.length); long t = a[i]; a[i] = a[j]; a[j] = t; } return a; } void shuffle(Object [] a) { Random r = new Random(); for (int i = a.length - 1; i >= 0; i--) { int j = r.nextInt(a.length); Object t = a[i]; a[i] = a[j]; a[j] = t; } } int [] sort(int [] a) { final int SHIFT = 16, MASK = (1 << SHIFT) - 1, SIZE = (1 << SHIFT) + 1; int n = a.length, ta [] = new int [n], ai [] = new int [SIZE]; for (int i = 0; i < n; ai[(a[i] & MASK) + 1]++, i++); for (int i = 1; i < SIZE; ai[i] += ai[i - 1], i++); for (int i = 0; i < n; ta[ai[a[i] & MASK]++] = a[i], i++); int [] t = a; a = ta; ta = t; ai = new int [SIZE]; for (int i = 0; i < n; ai[(a[i] >> SHIFT) + 1]++, i++); for (int i = 1; i < SIZE; ai[i] += ai[i - 1], i++); for (int i = 0; i < n; ta[ai[a[i] >> SHIFT]++] = a[i], i++); return ta; } void flush() { pw.flush(); } void pause() { flush(); System.console().readLine(); } }
JAVA
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; const int dr[]{-1, -1, 0, 1, 1, 1, 0, -1}; const int dc[]{0, 1, 1, 1, 0, -1, -1, -1}; void run() { ios::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL); } deque<int> solve(int n, int add) { if (n == 0) return {}; if (n == 1) return {1 + add}; deque<int> q = solve(n - 4, add + 2); q.push_front(n + add); q.push_front(2 + add); q.push_back(1 + add); q.push_back(n - 1 + add); return q; } int main() { run(); int n; cin >> n; if (n % 4 == 2 || n % 4 == 3) return cout << "-1", 0; deque<int> q = solve(n, 0); for (auto &it : q) cout << it << ' '; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; long a[100005]; int main() { long n; cin >> n; if (n == 1) cout << "1" << endl; else if (n % 4 == 0) { for (int i = 1; i <= n / 2; i += 2) a[n - i] = i; for (int i = 2; i <= n / 2; i += 2) a[i - 1] = i; for (int i = n; i > n / 2; i -= 2) a[n + 2 - i] = i; for (int i = n - 1; i > n / 2; i -= 2) a[i + 1] = i; for (int i = 1; i <= n - 1; i++) cout << a[i] << " "; cout << a[n] << endl; } else if ((n - 1) % 4 == 0) { a[n / 2 + 1] = n / 2 + 1; for (int i = 1; i <= n / 2; i += 2) a[n - i] = i; for (int i = 2; i <= n / 2; i += 2) a[i - 1] = i; for (int i = n; i > n / 2 + 1; i -= 2) a[n + 2 - i] = i; for (int i = n - 1; i > n / 2 + 1; i -= 2) a[i + 1] = i; for (int i = 1; i <= n - 1; i++) cout << a[i] << " "; cout << a[n] << endl; } else cout << "-1" << endl; return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
import java.io.IOException; import java.io.InputStream; import java.util.ArrayList; import java.util.NoSuchElementException; public class A { public static void main(String[] args) { FS r = new FS(); int N = r.nextInt(); int[] ans = new int[N]; if(N%4==2||N%4==3) { System.out.println(-1); return; } for(int i=1; i<=N/2; i++) { if(i%2==0) ans[i-2] = i; else ans[N-i-1] = i; } if(N%4==1) ans[N/2] = (N+1)/2; for(int i=N; i>(N+1)/2; i--) { if((N-i)%2==0) ans[N-i+1] = i; else ans[i] = i; } String[] print = new String[N]; for(int i=0; i<N; i++) print[i] = String.valueOf(ans[i]); System.out.println(String.join(" ", print)); } // Read Class static class FS { private final InputStream in = System.in; private final byte[] buffer = new byte[1024]; private int ptr = 0; private int buflen = 0; private boolean hasNextByte() { if (ptr < buflen) { return true; } else { ptr = 0; try { buflen = in.read(buffer); } catch (IOException e) { e.printStackTrace(); } if (buflen <= 0) { return false; } } return true; } private int readByte() { return hasNextByte() ? buffer[ptr++] : -1;} private boolean isPrintableChar(int c) {return 33 <= c && c <= 126;} private void skipUnprintable() {while(hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++;} public boolean hasNext() { skipUnprintable(); return hasNextByte();} public String next() { if (!hasNext()) throw new NoSuchElementException(); StringBuilder sb = new StringBuilder(); int b = readByte(); while(isPrintableChar(b)) { sb.appendCodePoint(b); b = readByte(); } return sb.toString(); } public int nextInt() { return (int)nextLong(); } public long nextLong() { if (!hasNext()) throw new NoSuchElementException(); long n = 0; boolean minus = false; int b = readByte(); if (b == '-') { minus = true; b = readByte(); } if (b < '0' || '9' < b) { throw new NumberFormatException(); } while(true) { if ('0' <= b && b <= '9') { n *= 10; n += b - '0'; } else if(b == -1 || !isPrintableChar(b)) { return minus ? -n : n; } else { throw new NumberFormatException(); } b = readByte(); } } } }
JAVA
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
/* * To change this license header, choose License Headers in Project Properties. * To change this template file, choose Tools | Templates * and open the template in the editor. */ //package codeforces; import java.util.*; import java.io.*; /** * * @author Arysson */ public class Main { /** * @param args the command line arguments */ public static void main(String[] args) { Scanner sc=new Scanner(System.in); int n=sc.nextInt(); if (n%4==2 || n%4==3) System.out.print(-1); else if (n%2==1) for (int i=1; i<=n; i++) { if (i==n/2+1) System.out.printf("%d ", n/2+1); else if (i<=n/2) System.out.printf("%d ", i%2==1?i+1:n-i+2); else System.out.printf("%d ", i%2==1?i-1:n-i); } else for (int i=1; i<=n; i++) { if (i<=n/2) System.out.printf("%d ", i%2==1?i+1:n-i+2); else System.out.printf ("%d ", i%2==1?n-i:i-1); } } }
JAVA
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
import java.util.Scanner; /** * Created with IntelliJ IDEA. * User: horikawa * Date: 3/23/13 * Time: 2:05 AM * To change this template use File | Settings | File Templates. */ public class C { public static void main (String[] argv) { Scanner in = new Scanner(System.in); int n = in.nextInt(); if ((n%4 != 0) && (n%4 != 1)) { System.out.println(-1); return; } int ans[] = new int[n+1]; for (int i=1; i<n/2; i+=2) { ans[i] = i+1; ans[i+1] = n-i+1; ans[n-i+1] = n-i; ans[n-i] = i; } if (n%4 == 1){ ans[(n+1)/2] = (n+1)/2; } for (int i=1; i<=n; i++) { System.out.print(ans[i]); if (i != n) { System.out.print(" "); } } System.out.println(); } }
JAVA
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
import java.util.*; import java.lang.*; import java.io.*; import java.text.*; /** * @author soumitri12 */ /* Name of the class has to be "Main" only if the class is public*/ public class CF287C { static class FastReader { BufferedReader br; StringTokenizer st; public FastReader() { br = new BufferedReader(new InputStreamReader(System.in)); } String next() { while (st == null || !st.hasMoreElements()) { try { st = new StringTokenizer(br.readLine()); } catch (IOException e) { e.printStackTrace(); } } return st.nextToken(); } int nextInt() { return Integer.parseInt(next()); } long nextLong() { return Long.parseLong(next()); } double nextDouble() { return Double.parseDouble(next()); } String nextLine() { String str = ""; try { str = br.readLine(); } catch (IOException e) { e.printStackTrace(); } return str; } } static class Node { long pp; long a, b; Node(long x, long y) { a = x; b = y; pp = a * b; } } static class Comp implements Comparator<Node> { public int compare(Node o1, Node o2) { if (o1.pp > o2.pp) { return 1; } else { return -1; } } } static int gcd(int x, int y) { if(y==0) return x; else return gcd(y,x%y); } static long mod_pow(long a, long b, long mod) { a%=mod; if(b==0) return 1%mod; if((b&1)==1) return a*(mod_pow(a,b-1,mod))%mod; else { long u=mod_pow(a,b>>1,mod); return (u*u)%mod; } } static long _pow(long a, long b) { if(b==0) return 1; if((b&1)==1) return a*_pow(a,b-1); else { long u=_pow(a,b>>1); return u*u; } } static int modInv(int a, int m) { if(gcd(a,m)!=1) return -999; else return (a%m+m)%m; } static boolean isPowerOfTwo(int x) { return x!=0 && ((x&(x-1)) == 0); } static boolean isprime(int x) { for(int i=2;i<=Math.sqrt(x);i++) { if(x%i==0) return false; } return true; } static boolean prime[]; static final int INT_MAX=1000007; static void sieve() { prime=new boolean[INT_MAX]; Arrays.fill(prime,true); prime[0]=prime[1]=false; for(int i=2;i<=Math.sqrt(INT_MAX);i++) { if(prime[i]) { for(int j=i*2;j<INT_MAX;j+=i) prime[j]=false; } } } static class Pair { int ff,ss; public Pair(int ff,int ss) { this.ff=ff; this.ss=ss; } } public static void main(String[] args) { FastReader sc=new FastReader(); PrintWriter out=new PrintWriter(System.out); StringBuffer sb=new StringBuffer(); //your code starts here int n=sc.nextInt(); int p[]=new int[n+1]; if((n&1)==1) p[(n+1)>>1]=(n+1)>>1; if((n&2)>=2) { System.out.println(-1); return; } for(int i=1;i<(n+1)>>1;i+=2) { if((i&1)==1) { p[i]=i+1; p[i+1]=n-i+1; p[n-i+1]=n+1-p[i];p[n-i]=i; } else { p[i]=i+2;p[n-i+1]=n+1-p[i]; p[i+1]=n-i+1;p[n-i]=i; } } for(int i=1;i<=n;i++) out.print(" "+p[i]); out.close(); } } ////
JAVA
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> const double eps = 1e-6; const double PI = acos(-1.0); const int inf = ~0u >> 2; using namespace std; const int N = 100010; int p[N]; int main() { int n, i; while (~scanf("%d", &n)) { if (n == 1) { puts("1"); continue; } if (n < 4) { puts("-1"); continue; } if (n % 4 != 0 && (n - 1) % 4 != 0) { puts("-1"); continue; } for (i = 1; i <= n / 4; ++i) { p[i] = i + n / 4; p[p[i]] = n - i + 1; p[p[p[i]]] = n - p[i] + 1; p[p[p[p[i]]]] = n - p[p[i]] + 1; } if ((n - 1) % 4 == 0) { p[n / 2 + 1] = n / 2 + 1; } for (i = 1; i < n; ++i) { printf("%d ", p[i]); } printf("%d\n", p[n]); } return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; const int N = 1e5 + 20; int n, p[N], ans1, ans2, ans3, ans4, k1, k2, k3, k4, m; int main() { cin >> n; if (n % 4 != 0 && (n - 1) % 4 != 0) { cout << -1; return 0; } if (n % 4 == 0) { m = n / 4; k1 = 1; k2 = 2; k3 = n - 1; k4 = n; ans1 = 2; ans2 = n; ans3 = 1; ans4 = n - 1; while (m--) { p[k1] = ans1; p[k2] = ans2; p[k3] = ans3; p[k4] = ans4; ans1 += 2; ans2 -= 2; ans3 += 2; ans4 -= 2; k1 += 2; k2 += 2; k3 -= 2; k4 -= 2; } } else { m = n / 4; k1 = 1; k2 = 2; k3 = n - 1; k4 = n; ans1 = 2; ans2 = n; ans3 = 1; ans4 = n - 1; while (m--) { p[k1] = ans1; p[k2] = ans2; p[k3] = ans3; p[k4] = ans4; ans1 += 2; ans2 -= 2; ans3 += 2; ans4 -= 2; k1 += 2; k2 += 2; k3 -= 2; k4 -= 2; } p[(n + 1) / 2] = (n + 1) / 2; } for (int i = 1; i <= n; i++) { cout << p[i] << " "; } return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
n = input () if (n==2 or n == 3 or 0 == (n-2)%4 or (n - 3)%4 == 0): print -1 else: if (n%2==0): for i in range(1, n/2+1): if (i%2==0): print i-1 else: print n - i for i in range(n/2 + (2 if (n%2==1) else 1), n+1): if (i%2==1): print i + 1 else: print n - i + 2 else: for i in range(1, n/2+1): if (i%2==0): print i-1 else: print n - i print n/2+1 for i in range(n/2 + 2, n+1): if (i%2==0): print i + 1 else: print n - i + 2
PYTHON
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; int main() { ifstream fin("input.txt", ios::in); ios_base::sync_with_stdio(false); cout.tie(0); cin.tie(0); cout << setprecision(10); cout << fixed; int n; cin >> n; if (n % 4 == 2 || n % 4 == 3) return cout << -1, 0; if (n == 1) return cout << 1, 0; int d[n]; if (n % 2 == 0) { for (int i = 0; i < n / 4; i++) { d[i * 2] = (i + 1) * 2; d[i * 2 + 1] = n - i * 2; d[n - i * 2 - 1] = n + 1 - 2 * (i + 1); d[n - i * 2 - 2] = i * 2 + 1; } } else { d[n / 2] = n / 2 + 1; for (int i = 0; i < n / 4; i++) { d[i * 2] = (i + 1) * 2; d[i * 2 + 1] = n - i * 2; d[n - i * 2 - 1] = n + 1 - 2 * (i + 1); d[n - i * 2 - 2] = i * 2 + 1; } } for (int i = 0; i < n; i++) cout << d[i] << " "; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; vector<int> vec; void cal(int l, int r) { if (r < l) return; if (l == r) { vec.push_back(l); return; } vec.push_back(l + 1); vec.push_back(r); cal(l + 2, r - 2); vec.push_back(l); vec.push_back(r - 1); } int main() { int n; cin >> n; if (n % 4 != 0 && n % 4 != 1) cout << -1 << endl; else { cal(1, n); for (int u : vec) cout << u << " "; cout << endl; } return 0; }
CPP
287_C. Lucky Permutation
A permutation p of size n is the sequence p1, p2, ..., pn, consisting of n distinct integers, each of them is from 1 to n (1 ≀ pi ≀ n). A lucky permutation is such permutation p, that any integer i (1 ≀ i ≀ n) meets this condition ppi = n - i + 1. You have integer n. Find some lucky permutation p of size n. Input The first line contains integer n (1 ≀ n ≀ 105) β€” the required permutation size. Output Print "-1" (without the quotes) if the lucky permutation p of size n doesn't exist. Otherwise, print n distinct integers p1, p2, ..., pn (1 ≀ pi ≀ n) after a space β€” the required permutation. If there are multiple answers, you can print any of them. Examples Input 1 Output 1 Input 2 Output -1 Input 4 Output 2 4 1 3 Input 5 Output 2 5 3 1 4
2
9
#include <bits/stdc++.h> using namespace std; int a[100001]; int main() { int i, n; cin >> n; if (n % 4 == 2 || n % 4 == 3) { cout << -1; return 0; } if (n % 2 == 1) a[(n + 1) / 2] = (n + 1) / 2; for (int i = 1; i <= n / 2; i += 2) { a[i] = i + 1; a[i + 1] = n - i + 1; a[n - i] = i; a[n - i + 1] = n - i; } cout << a[1]; for (int i = 2; i <= n; i++) cout << " " << a[i]; return 0; }
CPP