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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
#include <bits/stdc++.h> using namespace std; int v[100005] = {0}; int q[100005] = {0}; int main() { int n; scanf("%d", &n); memset(v, -1, sizeof(v)); if ((n - (n % 2)) % 4) { printf("-1\n"); return 0; } int cur = 0; int sz = 1; for (int i = 0; i < n / 2; i += 2) { q[cur] = i; v[i] = 0; if (n > 1) v[i] = i + 1; sz++; while (cur < sz) { int pos = q[cur]; if (v[v[pos]] == -1) { v[v[pos]] = n - pos - 1; q[sz++] = v[pos]; } else if (v[v[pos]] != n - pos - 1) { printf("-1\n"); return 0; } cur++; } } if (n % 2 != 0 && v[n / 2] == -1) v[n / 2] = n / 2, sz++; if (sz < n) { printf("-1\n"); return 0; } for (int i = 0; i < n; i++) printf("%d ", v[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.*; import java.util.*; public class A { public static void main(String[] args) { new A().run(); } BufferedReader br; StringTokenizer in; PrintWriter out; public 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 void solve() throws IOException { int n = nextInt(); if (n % 4 == 2 || n % 4 == 3) { out.println(-1); return; } int[] p = new int[n]; if (n % 4 == 1) p[n / 2] = n / 2; for (int i = 0; i < n / 2; i += 2) { p[i] = i + 1; p[i + 1] = n - i - 1; p[n - i - 1] = n - i - 2; p[n - i - 2] = i; } for (int i = 0; i < p.length; i++) { out.print((p[i] + 1) + " "); } } public void run() { try { br = new BufferedReader(new InputStreamReader(System.in)); out = new PrintWriter(System.out); solve(); out.close(); } catch (IOException e) { e.printStackTrace(); } } }
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 arr[100005]; int main() { memset(arr, -1, sizeof arr); int n; cin >> n; if (n & 1) arr[n / 2 + 1] = n / 2 + 1; for (int i = 1; i < n / 2; i += 2) { arr[i] = i + 1; arr[i + 1] = n - i + 1; arr[n - i] = i; arr[n - i + 1] = n - i; } for (int i = 1; i <= n; i++) { if (arr[i] == -1) { puts("-1"); exit(0); } } for (int i = 1; i <= n; i++) cout << arr[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 sys n = int(sys.stdin.read().strip()) if n == 1: res = [1] elif n % 4 in [2, 3]: res = [-1] elif n % 4 == 1: res = [0] * n for i in xrange(0, n, 2): res[i] = i+2 for i in xrange(1, n, 2): res[i] = n-i-1 for i in xrange(n/2, n, 2): res[i] -= 2 for i in xrange(1, n/2, 2): res[i] += 2 res[n/2] = n/2 + 1 else: res = [0] * n for i in xrange(0, n/2, 2): res[i] = i+2 for i in xrange(n/2, n, 2): res[i] = n-i-1 for i in xrange(1, n/2, 2): res[i] = n-i+1 for i in xrange(n/2+1, n, 2): res[i] = i sys.stdout.write(' '.join([str(i) for i in res]))
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.*; import java.math.*; import java.io.*; public class A{ static FastReader scan=new FastReader(); public static PrintWriter out = new PrintWriter (new BufferedOutputStream(System.out)); static LinkedList<Edge>edges[]; static boolean stdin = true; static String filein = "input"; static String fileout = "output"; static int dx[] = { -1, 0, 1, 0 }; static int dy[] = { 0, 1, 0, -1 }; int dx_8[]={1,1,1,0,0,-1,-1,-1}; int dy_8[]={-1,0,1,-1,1,-1,0,1}; static char sts[]={'U','R','D','L'}; static boolean prime[]; static long LCM(long a,long b){ return (Math.abs(a*b))/gcd(a,b); } public static int upperBound(long[] array, int length, long value) { int low = 0; int high = length; while (low < high) { final int mid = low+(high-low) / 2; if ( array[mid]>value) { high = mid ; } else { low = mid+1; } } return low; } static long gcd(long a, long b) { if(a!=0&&b!=0) while((a%=b)!=0&&(b%=a)!=0); return a^b; } static int countSetBits(int n) { int count = 0; while (n > 0) { if((n&1)!=1) count++; //count += n & 1; n >>= 1; } return count; } static void sieve(long n) { prime = new boolean[(int)n+1]; for(int i=0;i<n;i++) prime[i] = true; for(int p = 2; p*p <=n; p++) { if(prime[p] == true) { for(int i = p*p; i <= n; i += p) prime[i] = false; } } } static boolean isprime(long x) { for(long i=2;i*i<=x;i++) if(x%i==0) return false; return true; } static int perm=0,FOR=0; static boolean flag=false; static int len=100000000; static ArrayList<Pair>inters=new ArrayList<Pair>(); static StringBuilder sb; static void swap(int i,int j,StringBuilder st) { char tmp=st.charAt(i); st.setCharAt(i,st.charAt(j)); st.setCharAt(j,tmp); } private static int next(int[] arr, int target) { int start = 0, end = arr.length - 1; int ans = -1; while (start <= end) { int mid = (start + end) / 2; // Move to right side if target is // greater. if(arr[mid]==target) return mid; if (arr[mid] <target) { start = mid + 1; } // Move left side. else { ans = mid; end = mid - 1; } } return ans; } //static boolean vis[][]; static long solve(int h,long n,int cur) { if(h==0) return 0; long half=1L<<(h-1); if(n<=half) { if((cur^1)==0) return 1+solve(h-1,n,0); else return 2*half+solve(h-1,n,0); } else { if((cur^1)==0) return 2*half+solve(h-1,n-half,1); else return 1+solve(h-1,n-half,1); } } public static class comp1 implements Comparator<String>{ public int compare(String o1,String o2){ return o1.length()-o2.length(); } } public static class comp2 implements Comparator<String>{ public int compare(String o1,String o2){ return o1.compareTo(o2); } } static StringBuilder a,b; static boolean isPowerOfTwo(int n) { if(n==0) return false; return (int)(Math.ceil((Math.log(n) / Math.log(2)))) == (int)(Math.floor(((Math.log(n) / Math.log(2))))); } static ArrayList<Integer>v; static ArrayList<Integer>pows; static void block(long x) { v = new ArrayList<Integer>(); pows=new ArrayList<Integer>(); while (x > 0) { v.add((int)x % 2); x = x / 2; } // Displaying the output when // the bit is '1' in binary // equivalent of number. for (int i = 0; i < v.size(); i++) { if (v.get(i) == 1) { pows.add(i); } } } static int n; static int h,m; static StringBuilder tmp; static boolean check(StringBuilder x) { tmp=new StringBuilder(x); tmp.reverse(); if(tmp.charAt(0)=='3'||tmp.charAt(0)=='4'||tmp.charAt(0)=='6'||tmp.charAt(0)=='7'||tmp.charAt(0)=='9') return false; if(tmp.charAt(1)=='3'||tmp.charAt(1)=='4'||tmp.charAt(1)=='6'||tmp.charAt(1)=='7'||tmp.charAt(1)=='9') return false; if(tmp.charAt(3)=='3'||tmp.charAt(3)=='4'||tmp.charAt(3)=='6'||tmp.charAt(3)=='7'||tmp.charAt(3)=='9') return false; if(tmp.charAt(4)=='3'||tmp.charAt(4)=='4'||tmp.charAt(4)=='6'||tmp.charAt(4)=='7'||tmp.charAt(4)=='9') return false; if(tmp.charAt(0)=='2') tmp.setCharAt(0,'5'); else if(tmp.charAt(0)=='5') tmp.setCharAt(0,'2'); if(tmp.charAt(1)=='2') tmp.setCharAt(1,'5'); else if(tmp.charAt(1)=='5') tmp.setCharAt(1,'2'); if(tmp.charAt(3)=='2') tmp.setCharAt(3,'5'); else if(tmp.charAt(3)=='5') tmp.setCharAt(3,'2'); if(tmp.charAt(4)=='5') tmp.setCharAt(4,'2'); else if(tmp.charAt(4)=='2') tmp.setCharAt(4,'5'); // if(x.toString().equals("50:00")) // out.println(tmp.charAt(4)); StringBuilder s=new StringBuilder(""); s.append(tmp.charAt(0)); s.append(tmp.charAt(1)); if(Integer.parseInt(s.toString())>=h) return false; s=new StringBuilder(""); s.append(tmp.charAt(3)); s.append(tmp.charAt(4)); if(Integer.parseInt(s.toString())>=m) return false; return true; } public static void main(String[] args) throws Exception { //SUCK IT UP AND DO IT ALRIGHT //scan=new FastReader("div7.in"); //out = new PrintWriter("div7.out"); //System.out.println(countSetBits(2015)); //int elem[]={1,2,3,4,5}; //System.out.println("avjsmlfpb".compareTo("avjsmbpfl")); int tt=1; /*for(int i=0;i<=100;i++) if(prime[i]) arr.add(i); System.out.println(arr.size());*/ // check(new StringBuilder("05:11")); //System.out.println(tmp); // tt=scan.nextInt(); outer:while(tt-->0) { int n=scan.nextInt(); int idx=1; int arr[]=new int[n+1]; //int el=2; //0 0 0 0 0 0 0 //arr[1]=el; //el=2 idx=1 int el=2; int k=2; //out.println(5/4); int tmp=n; idx=1; for(int j=0;j<=n/4&&tmp>1;j++,tmp-=4){ for(int i=1;i<=4;i++) { // System.out.println(el); arr[el]=n-idx+1; idx=el; el=arr[el]; //out.println(el+" "+idx); } //for(int i=1;i<=n;i++) //out.print(arr[i]+" "); //out.println(); idx+=2; el+=2; } if(n%2==1) { arr[n/2+1]=n/2+1; } for(int i=1;i<=n;i++) { if(arr[arr[i]]!=n-i+1){ out.println(-1); out.close(); return; } } for(int i=1;i<=n;i++) out.print(arr[i]+" "); } out.close(); //SEE UP } static class special{ char c; int idx; special(char c,int idx) { this.c=c; this.idx=idx; } } static long binexp(long a,long n) { if(n==0) return 1; long res=binexp(a,n/2); if(n%2==1) return res*res*a; else return res*res; } static long powMod(long base, long exp, long mod) { if (base == 0 || base == 1) return base; if (exp == 0) return 1; if (exp == 1) return base % mod; long R = powMod(base, exp/2, mod) % mod; R *= R; R %= mod; if ((exp & 1) == 1) { return base * R % mod; } else return R % mod; } static double dis(double x1,double y1,double x2,double y2) { return Math.sqrt((x1-x2)*(x1-x2)+(y1-y2)*(y1-y2)); } static long mod(long x,long y) { if(x<0) x=x+(-x/y+1)*y; return x%y; } public static long pow(long b, long e) { long r = 1; while (e > 0) { if (e % 2 == 1) r = r * b ; b = b * b; e >>= 1; } return r; } private static void sort(long[] arr) { List<Long> list = new ArrayList<>(); for (long object : arr) list.add(object); Collections.sort(list); for (int i = 0; i < list.size(); ++i) arr[i] = list.get(i); } public static class FastReader { BufferedReader br; StringTokenizer root; public FastReader() { br = new BufferedReader(new InputStreamReader(System.in)); } FastReader(String filename)throws Exception { br=new BufferedReader(new FileReader(filename)); } boolean hasNext(){ String line; while(root.hasMoreTokens()) return true; return false; } String next() { while (root == null || !root.hasMoreTokens()) { try { root = new StringTokenizer(br.readLine()); } catch (Exception addd) { addd.printStackTrace(); } } return root.nextToken(); } int nextInt() { return Integer.parseInt(next()); } double nextDouble() { return Double.parseDouble(next()); } long nextLong() { return Long.parseLong(next()); } String nextLine() { String str = ""; try { str = br.readLine(); } catch (Exception addd) { addd.printStackTrace(); } return str; } public int[] nextIntArray(int arraySize) { int array[] = new int[arraySize]; for (int i = 0; i < arraySize; i++) { array[i] = nextInt(); } return array; } } static class Pair implements Comparable<Pair>{ public int x, y; public Pair(int x1, int y1) { x=x1; y=y1; } @Override public int hashCode() { return (int)(x + 31 * y); } public String toString() { return x + " " + y; } @Override public boolean equals(Object o){ if (o == this) return true; if (o.getClass() != getClass()) return false; Pair t = (Pair)o; return t.x == x && t.y == y; } public int compareTo(Pair o) { return (x-o.x); } static class pair{ int i; int j; pair(int i,int j){ this.i=i; this.j=j; }}} static class tuple{ int x,y,z; tuple(int a,int b,int c){ x=a; y=b; z=c; } } static class Edge{ int d,w; Edge(int d,int w) { this.d=d; this.w=w; } } }
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
a = [0]*100010 n = int(raw_input()) if n % 4 > 1: print '-1' else: stpos = 1 edpos = n-1 stval = 2 edval = 1 cnt = n/4 for i in range(cnt): a[stpos] = stval a[edpos] = edval a[stpos+1] = n +2 - stval a[edpos+1] = n - edval stpos += 2 edpos -= 2 stval += 2 edval += 2 if n % 4 == 1: a[stpos] = stval - 1 for i in range(1,n+1): print a[i], print '\n'
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
n = input() p = [] for i in range(0, n / 2, 2): p += [i + 2, n - i] if n % 4: p += [n / 2 + 1] for i in range(n / 2 - 1, 0, -2): p += [i, n - i] if n % 4 > 1: p = [-1] print ' '.join(map(str, p))
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.io.OutputStream; import java.io.IOException; import java.io.InputStream; import java.io.PrintWriter; import java.io.OutputStream; import java.io.IOException; import java.io.InputStreamReader; import java.io.File; import java.io.FileNotFoundException; import java.util.StringTokenizer; import java.io.Writer; import java.io.BufferedReader; import java.io.FileReader; import java.io.InputStream; /** * Built using CHelper plug-in * Actual solution is at the top * @author zodiacLeo */ public class Main { public static void main(String[] args) { InputStream inputStream = System.in; OutputStream outputStream = System.out; FastScanner in = new FastScanner(inputStream); FastPrinter out = new FastPrinter(outputStream); TaskC solver = new TaskC(); solver.solve(1, in, out); out.close(); } static class TaskC { public void solve(int testNumber, FastScanner in, FastPrinter out) { int n = in.nextInt(); if (n == 1) { out.println(1); return; } if (n == 2) { out.println(-1); return; } if (n % 4 > 1) { out.println(-1); return; } int[] a = new int[n + 1]; for (int i = 1; i < n / 2; i += 2) { int p1 = i; int q1 = n + 1 - i; int p2 = p1 + 1; int q2 = q1 - 1; a[p1] = p2; a[p2] = q1; a[q1] = q2; a[q2] = p1; } if (n % 2 != 0) { a[(n / 2) + 1] = (n / 2) + 1; } StringBuilder sb = new StringBuilder(""); for (int i = 1; i <= n; i++) { sb.append(a[i] + " "); } out.println(sb); } } static class FastScanner { public BufferedReader br; public StringTokenizer st; public FastScanner(InputStream is) { br = new BufferedReader(new InputStreamReader(is)); } public FastScanner(File f) { try { br = new BufferedReader(new FileReader(f)); } catch (FileNotFoundException e) { e.printStackTrace(); } } public String next() { while (st == null || !st.hasMoreElements()) { String s = null; try { s = br.readLine(); } catch (IOException e) { e.printStackTrace(); } if (s == null) return null; st = new StringTokenizer(s); } return st.nextToken(); } public int nextInt() { return Integer.parseInt(next()); } } static class FastPrinter extends PrintWriter { public FastPrinter(OutputStream out) { super(out); } public FastPrinter(Writer out) { super(out); } } }
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.InputStreamReader; import java.io.IOException; import java.io.BufferedReader; import java.io.OutputStream; import java.io.PrintWriter; import java.util.StringTokenizer; import java.io.InputStream; /** * Built using CHelper plug-in * Actual solution is at the top * @author vadimmm */ 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 { public void solve(int testNumber, InputReader in, PrintWriter out) { int n = in.nextInt(); if ((n & 3) > 1) out.println(-1); else { int[] permutation = new int[n + 1]; int up = n >> 1; if ((n & 1) == 1) permutation[up + 1] = up + 1; for (int i = 1; i <= up; i += 2) { permutation[i] = i + 1; permutation[n - i + 1] = n - i; permutation[i + 1] = n - i + 1; permutation[n - i] = i; } out.print(permutation[1]); for (int i = 2; i <= n; ++i) { out.print(" "); out.print(permutation[i]); } } } } class InputReader { private static BufferedReader bufferedReader; private static StringTokenizer stringTokenizer; public InputReader(InputStream inputStream) { bufferedReader = new BufferedReader(new InputStreamReader(inputStream)); stringTokenizer = null; } public String next() { while(stringTokenizer == null || !stringTokenizer.hasMoreTokens()) { try { stringTokenizer = new StringTokenizer(bufferedReader.readLine()); } catch (IOException e) { e.printStackTrace(); } } return stringTokenizer.nextToken(); } public int nextInt() { 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> long a[110000]; int main() { int n, i, j; scanf("%d", &n); if ((n % 4) > 1) { 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 % 2) == 1) { a[n / 2 + 1] = n / 2 + 1; } printf("%d", a[1]); for (i = 2; 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
import java.util.Scanner; public class CodeForces { public static void main(String[] args) { Scanner s = new Scanner(System.in); while (s.hasNext()) { int n = s.nextInt(); int[] p = new int[n+1]; p = getLuckyPerm(p, n); if (p[0] == 0) { System.out.println("-1"); } else { for (int i=1; i <= n; i++) { System.out.print(p[i]); if (i != n) { System.out.print(' '); } } } } } public static int[] getLuckyPerm(int[] p, int n) { int m = -1; switch ( n%2 ) { case 1: m = (n+1)/2 - 1; p[m+1] = m+1; break; case 0: m = (n+1)/2; break; default: break; } if ( m%2 == 0) { for (int i=1; i <= m-1; i+=2) { p[i] = i+1; p[i+1] = n-i+1; p[n-i] = i; p[n-i+1] = n-i; } p[0] = 1; } else { p[0] = 0; } return p; } }
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 int N = 100100; using namespace std; int n, p[N]; int l; void dfs(int x) { p[p[x]] = n - x + 1; int y = p[x]; while (y != x) { p[p[y]] = n - y + 1; y = p[y]; } } int main() { ios_base::sync_with_stdio(0); cin >> n; if (n % 2) p[n / 2 + 1] = n / 2 + 1; for (int i = 1; i <= n; i++) { if (p[i]) continue; l = i; p[i] = i + 1; dfs(i); } for (int i = 1; i <= n; i++) { if (p[p[i]] != n - i + 1) { cout << -1 << endl; return 0; } } for (int i = 1; i <= n; i++) cout << p[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> int n, t, a[110000], tnum, cas; int main() { cas = 0; scanf("%d", &n); if (n == 1) { printf("1\n"); } else { if (n % 2 != 0) { a[(n / 2) + 1] = (n / 2) + 1; tnum = n - 1; } else { tnum = n; } if (tnum % 4 != 0) { printf("-1\n"); } else { for (int i = 1; i <= n / 2; i += 2) { a[i] = n - i; a[n - i] = n - i + 1; a[n - i + 1] = i + 1; a[i + 1] = i; } for (int i = 1; i <= n; i++) { printf("%d", a[i]); if (i != n) { printf(" "); } } 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.BufferedWriter; import java.io.IOException; import java.io.InputStreamReader; import java.io.OutputStreamWriter; import java.io.PrintWriter; import java.io.StreamTokenizer; public class C { static StreamTokenizer st; static PrintWriter pw; private static int nextInt() throws IOException { st.nextToken(); return (int) st.nval; } public static void main(String[] args) throws IOException { st = new StreamTokenizer(new BufferedReader(new InputStreamReader( System.in))); pw = new PrintWriter(new BufferedWriter(new OutputStreamWriter( System.out))); // -----------begin------------------------- int n = nextInt(); if ((n - 1) % 4 == 1 || (n - 1) % 4 == 2) { pw.println("-1"); pw.close(); return; } if (n % 2 == 0) { for (int i = 0; i < n/2; i += 2) { pw.print(i + 2+ " "); pw.print(n-i+" "); } int a[][] = new int [n/2][2]; int cnt = 0; for (int i = 0; i < n/2; i += 2) { a[cnt][0] = i+1; a[cnt][1] = n-i-1; cnt++; } for (int i = cnt-1; i >= 0; i--) { pw.print(a[i][0]+" "); pw.print(a[i][1]+" "); } } else { for (int i = 0; i < n/2; i += 2) { pw.print(i + 2+ " "); pw.print(n-i+" "); } int a[][] = new int [n/2][2]; int cnt = 0; for (int i = 0; i < n/2; i += 2) { a[cnt][0] = i+1; a[cnt][1] = n-i-1; cnt++; } pw.print(n/2+1+" "); for (int i = cnt-1; i >= 0; i--) { pw.print(a[i][0]+" "); pw.print(a[i][1]+" "); } } // pw.print(n); pw.close(); // ------------end-------------------------- } }
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; bool flag[20]; int ans[20]; bool dfs(int k, int n) { if (k > n) { bool temp = true; for (int i = 1; i <= n; i++) if (ans[ans[i]] != n - i + 1) temp = false; if (temp) { for (int i = 1; i <= n; i++) printf("%d ", ans[i]); printf("\n"); return true; } return false; } for (int i = 1; i <= n; i++) if (flag[i]) { flag[i] = false; ans[k] = i; bool temp = dfs(k + 1, n); if (temp) return true; flag[i] = true; } } int main() { int n; scanf("%d", &n); if (n == 1) { printf("1\n"); return 0; } if (((n) / 2) % 2 == 1) { printf("-1\n"); return 0; } int out[100010]; out[0] = 2; out[1] = n; out[n - 1] = n - 1; out[n - 2] = 1; int head = 2; int tail = n - 3; while (head < tail) { if (head % 2 == 0) out[head] = out[head - 2] + 2; else out[head] = out[head - 2] - 2; if ((n - 1 - tail) % 2 == 0) out[tail] = out[tail + 2] - 2; else out[tail] = out[tail + 2] + 2; head++; tail--; } if (head == tail) out[head] = (n + 1) / 2; printf("%d", out[0]); for (int i = 1; i < n; i++) printf(" %d", out[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; scanf("%d", &n); if (n % 4 == 2 || n % 4 == 3) { cout << -1; return 0; } int ans[n + 10]; if (n % 4 == 1) { ans[n / 2 + 1] = n / 2 + 1; } for (int i = 1; i < n / 2; i += 2) { ans[i] = i + 1; ans[i + 1] = n + 1 - i; ans[n + 1 - i] = n - i; ans[n - i] = i; } for (int i = 1; i <= n; i++) cout << ans[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 == 2 || n % 4 == 3) { printf("-1\n"); return 0; } int lo, hi; int A[100006]; lo = 1; hi = n; while (lo < hi) { A[lo] = lo + 1; A[lo + 1] = hi; A[hi] = hi - 1; A[hi - 1] = lo; lo += 2; hi -= 2; } if (lo == hi) A[lo] = lo; for (int i = 1; i < n + 1; i++) printf("%d ", 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> int a[100001]; 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 = i + 2) { a[i] = i + 1; a[i + 1] = n + 1 - i; a[n - i] = i; a[n + 1 - i] = n - i; } if (n % 4 == 1) a[i] = i; 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> using namespace std; int a[100005]; int main() { int n; cin >> n; if (n % 4 >= 2) return puts("-1"), 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] << " \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; int a[100005], n; bool tui() { int nd2 = n / 2, w = 2; if (n % 4 == 0) { for (int i = 1; i <= nd2; i += 2) { a[i] = w, a[i + 1] = n + 2 - w; w += 2; } w = nd2 - 1; for (int i = nd2 + 1; i <= n; i += 2) { a[i] = w, a[i + 1] = n - w, w -= 2; } } else if (n % 4 == 1) { a[n / 2 + 1] = n / 2 + 1; for (int i = 1; i <= nd2; i += 2) { a[i] = w, a[i + 1] = n + 2 - w; w += 2; } w = nd2 - 1; for (int i = nd2 + 2; i <= n; i += 2) { a[i] = w, a[i + 1] = n - w, w -= 2; } } else return false; return true; } int main() { scanf("%d", &n); if (n == 1) { printf("1\n"); return 0; } a[1] = 2; if (tui()) { for (int i = 1; i < n; ++i) printf("%d ", a[i]); printf("%d\n", a[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> int p[100009], n, s, t, i; bool none = false; int main() { scanf("%d", &n); for (s = 1, t = n; s <= t;) { if (t - s + 1 >= 4) { p[s] = s + 1; p[s + 1] = t; p[t] = t - 1; p[t - 1] = s; s += 2; t -= 2; } else { if (t - s + 1 >= 2) { none = 1; break; } else { p[s] = t; s++; t--; } } } if (none) printf("-1\n"); else for (i = 1; i <= n; i++) printf("%d ", p[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
n = input() if 2 == n % 4 or 3 == n % 4: print -1 exit() cnt4 = n / 4 a = [0] * n i = 0 while cnt4 > 0: cnt4 -= 1 a[i] = i + 2 a[i + 1] = n - i a[n - 1 - i] = n - i - 1 a[n - 2 - i] = i + 1 i += 2 if 1 == n % 4: a[i] = i + 1 for x in a: print x,
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 a[100009]; bool FL; void f(int st, int en, int i, int j) { if (st > en) return; if (st == en) a[i] = st; else { if ((j - i) == 1 || (j - i) == 2) { FL = false; return; } a[i] = st + 1; a[i + 1] = en; a[j] = en - 1; a[j - 1] = st; f(st + 2, en - 2, i + 2, j - 2); } } int main() { int n; cin >> n; FL = true; f(1, n, 1, n); if (FL) { for (typeof(1) i = (1); i < (n); i++) cout << a[i] << " "; cout << a[n] << "\n"; for (typeof(1) i = (1); i < (n + 1); i++) assert(a[a[i]] == (n - i + 1)); } else cout << "-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
n = int(input()) if n%4 > 1: print(-1) exit() a = [(n+1) // 2] * n for i in range(n//4): j = 2*i a[j], a[j+1], a[-j-2], a[-j-1] = j+2, n-j, j+1, n-j-1 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
#include <bits/stdc++.h> using namespace std; long long int inf = 1e14; long long int mod = 1e9 + 7; char en = '\n'; long long int arr[300005]; long long int res[300005]; int main() { ios_base::sync_with_stdio(false); cin.tie(NULL); memset(arr, 0, sizeof(arr)); long long int n; cin >> n; if ((n % 4 == 2) or (n % 4 == 3)) { cout << -1 << en; return 0; } long long int leftPtr = 100000, rightPtr; vector<long long int> left1, right1; vector<long long int> curr; if (n & 1) { curr.push_back(1); rightPtr = 100000; } else { rightPtr = 100003; curr.push_back(2); curr.push_back(4); curr.push_back(1); curr.push_back(3); } long long int currSize = curr.size() + 4; while (currSize <= n) { arr[leftPtr] += 2; arr[rightPtr + 1] -= 2; leftPtr -= 2; rightPtr += 2; left1.push_back(currSize); left1.push_back(2); right1.push_back(1); right1.push_back(currSize - 1); currSize += 4; } long long int cnt = 0; reverse(left1.begin(), left1.end()); for (long long int x : left1) res[++cnt] = x; for (long long int x : curr) res[++cnt] = x; for (long long int x : right1) res[++cnt] = x; for (long long int i = leftPtr; i <= rightPtr; i++) { arr[i] += arr[i - 1]; cout << res[i - leftPtr + 1] + 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
import java.io.*; import java.util.*; public class Main { private InputStream is; private PrintWriter out; int time = 0, val[][], dp[][], DP[], start[], end[], dist[], black[], MOD = (int)(1e9+7), arr[], weight[][], x[], y[], parent[]; int MAX = 800000, N, K; long red[]; ArrayList<Integer>[] amp; ArrayList<Pair>[][] pmp; boolean b[], boo[][]; Pair prr[]; HashMap<Integer,Long> hm[] = new HashMap[305]; long Dp[][][][] = new long[110][110][12][12]; void soln() { is = System.in; out = new PrintWriter(System.out); long s = System.currentTimeMillis(); solve(); //out.close(); out.flush(); //tr(System.currentTimeMillis() - s + "ms"); } public static void main(String[] args) throws Exception { new Thread(null, new Runnable() { public void run() { try { //new CODEFORCES().soln(); } catch (Exception e) { System.out.println(e); } } }, "1", 1 << 26).start(); new Main().soln(); } int ans = 0, cost = 0; char ch[], ch1[]; void solve() { int n = ni(); if(n==1){ System.out.println(1); return;} if(n%4==2 || n%4==3){ System.out.println(-1); return; } int arr[] = new int[n+10]; if(n%4==0){ int c = 1; for(int i = 2;i<=n/2;i+=2){ arr[c] = i; arr[c+1] = n-i+2; c+=2; } c = n-1; for(int i = 1;i<n/2;i+=2){ arr[c] = i; arr[c+1] = n-i; c-=2; } } if(n%4==1){ arr[(n+1)/2] = (n+1)/2; int c = 1; for(int i = 2;i<=n/2;i+=2){ arr[c] = i; arr[c+1] = n-i+2; c+=2; } c = n; for(int i = n-1;i>n/2;i-=2){ arr[c] = i; arr[c-1] = n-i; c-=2; } } /*int arr[] = new int[n+10]; arr[1] = 2; arr[2] = n; arr[n] = n-1; arr[n-1] = 1; int x = 3, y = n-2; for(int i = n-2;i>(n+1)/2;i--){ arr[i] = x++; arr[n-i+1] = y--; } if(n%2==1) arr[(n+1)/2] = (n+1)/2; //System.out.println(ts); //if(n%2==0) arr[3] = 3;*/ for(int i = 1;i<=n;i++) out.print(arr[i]+" "); } class Pair implements Comparable<Pair>{ int u, v, i; Pair(int u, int v){ this.u = u; this.v = v; } Pair(){ } Pair(int u, int v, int i){ this.u = u; this.v = v; this.i = i; } public int hashCode() { return Objects.hash(); } public boolean equals(Object o) { Pair other = (Pair) o; return ((u == other.u && v == other.v)); } public int compareTo(Pair other) { //return Integer.compare(val, other.val); return Long.compare(u, other.u) != 0 ? (Long.compare(u, other.u)) : (Long.compare(v,other.v)); } public String toString(){ return this.u +" " + this.v; } } int max(int a, int b){ if(a>b) return a; return b; } public static class FenwickTree { int[] array; // 1-indexed array, In this array We save cumulative information to perform efficient range queries and updates public FenwickTree(int size) { array = new int[size + 1]; } public int rsq(int ind) { assert ind > 0; int sum = 0; while (ind > 0) { sum += array[ind]; //Extracting the portion up to the first significant one of the binary representation of 'ind' and decrementing ind by that number ind -= ind & (-ind); } return sum; } public int rsq(int a, int b) { assert b >= a && a > 0 && b > 0; return rsq(b) - rsq(a - 1); } public void update(int ind, int value) { assert ind > 0; while (ind < array.length) { array[ind] += value; //Extracting the portion up to the first significant one of the binary representation of 'ind' and incrementing ind by that number ind += ind & (-ind); } } public int size() { return array.length - 1; } } void buildGraph(int n){ for(int i = 0; i<n ;i++){ int x1 = ni() -1, y1 = ni()-1; amp[x1].add(y1); amp[y1].add(x1); x[i] = x1; y[i] = y1; } } long modInverse(long a, long mOD2){ return power(a, mOD2-2, mOD2); } long power(long x, long y, long m) { if (y == 0) return 1; long p = power(x, y/2, m) % m; p = (p * p) % m; return (y%2 == 0)? p : (x * p) % m; } public int gcd(int a, int b){ if(b==0) return a; return gcd(b,a%b); } static class ST1{ int arr[], st[], size; ST1(int a[]){ arr = a.clone(); size = 10*arr.length; st = new int[size]; build(0,arr.length-1,1); } void build(int ss, int se, int si){ if(ss==se){ st[si] = arr[ss]; return; } int mid = (ss+se)/2; int val = 2*si; build(ss,mid,val); build(mid+1,se,val+1); st[si] = Math.min(st[val], st[val+1]); } int get(int ss, int se, int l, int r, int si){ if(l>se || r<ss || l>r) return Integer.MAX_VALUE; if(l<=ss && r>=se) return st[si]; int mid = (ss+se)/2; int val = 2*si; return Math.min(get(ss,mid,l,r,val), get(mid+1,se,l,r,val+1)); } } static class ST{ int arr[],lazy[],n; ST(int a){ n = a; arr = new int[10*n]; lazy = new int[10*n]; } void up(int l,int r,int val){ update(0,n-1,0,l,r,val); } void update(int l,int r,int c,int x,int y,int val){ if(lazy[c]!=0){ lazy[2*c+1]+=lazy[c]; lazy[2*c+2]+=lazy[c]; if(l==r) arr[c]+=lazy[c]; lazy[c] = 0; } if(l>r||x>y||l>y||x>r) return; if(x<=l&&y>=r){ lazy[c]+=val; return ; } int mid = l+r>>1; update(l,mid,2*c+1,x,y,val); update(mid+1,r,2*c+2,x,y,val); arr[c] = Math.max(arr[2*c+1], arr[2*c+2]); } int an(int ind){ return ans(0,n-1,0,ind); } int ans(int l,int r,int c,int ind){ if(lazy[c]!=0){ lazy[2*c+1]+=lazy[c]; lazy[2*c+2]+=lazy[c]; if(l==r) arr[c]+=lazy[c]; lazy[c] = 0; } if(l==r) return arr[c]; int mid = l+r>>1; if(mid>=ind) return ans(l,mid,2*c+1,ind); return ans(mid+1,r,2*c+2,ind); } } public static int[] shuffle(int[] a, Random gen){ for(int i = 0, n = a.length;i < n;i++) { int ind = gen.nextInt(n-i)+i; int d = a[i]; a[i] = a[ind]; a[ind] = d; } return a; } long power(long x, long y, int mod){ long ans = 1; while(y>0){ if(y%2==0){ x = (x*x)%mod; y/=2; } else{ ans = (x*ans)%mod; y--; } } return ans; } // To Get Input // Some Buffer Methods private byte[] inbuf = new byte[1024]; public int lenbuf = 0, ptrbuf = 0; private int readByte() { if (lenbuf == -1) throw new InputMismatchException(); if (ptrbuf >= lenbuf) { ptrbuf = 0; try { lenbuf = is.read(inbuf); } catch (IOException e) { throw new InputMismatchException(); } if (lenbuf <= 0) return -1; } return inbuf[ptrbuf++]; } private boolean isSpaceChar(int c) { return !(c >= 33 && c <= 126); } private int skip() { int b; while ((b = readByte()) != -1 && isSpaceChar(b)) ; return b; } private double nd() { return Double.parseDouble(ns()); } private char nc() { return (char) skip(); } private String ns() { int b = skip(); StringBuilder sb = new StringBuilder(); while (!(isSpaceChar(b))) { // when nextLine, (isSpaceChar(b) && b != ' // ') sb.appendCodePoint(b); b = readByte(); } return sb.toString(); } private char[] ns(int n) { char[] buf = new char[n]; int b = skip(), p = 0; while (p < n && !(isSpaceChar(b))) { buf[p++] = (char) b; b = readByte(); } return n == p ? buf : Arrays.copyOf(buf, p); } private char[][] nm(int n, int m) { char[][] map = new char[n][]; for (int i = 0; i < n; i++) map[i] = ns(m); return map; } private int[] na(int n) { int[] a = new int[n]; for (int i = 0; i < n; i++) a[i] = ni(); return a; } private int ni() { int num = 0, b; boolean minus = false; while ((b = readByte()) != -1 && !((b >= '0' && b <= '9') || b == '-')) ; if (b == '-') { minus = true; b = readByte(); } while (true) { if (b >= '0' && b <= '9') { num = num * 10 + (b - '0'); } else { return minus ? -num : num; } b = readByte(); } } private long nl() { long num = 0; int b; boolean minus = false; while ((b = readByte()) != -1 && !((b >= '0' && b <= '9') || b == '-')) ; if (b == '-') { minus = true; b = readByte(); } while (true) { if (b >= '0' && b <= '9') { num = num * 10 + (b - '0'); } else { return minus ? -num : num; } b = readByte(); } } private boolean oj = System.getProperty("ONLINE_JUDGE") != null; private void tr(Object... o) { if (!oj) System.out.println(Arrays.deepToString(o)); } }
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, x, y, a[100010]; int main() { scanf("%d", &n); if (n % 4 != 0 && n % 4 != 1) { printf("-1"); return 0; } for (int i = 1; i <= n / 2; i += 2) { int x = i, y = i + 1; for (int j = 1; j <= 4; j++) { a[x] = y; y = n - x + 1; x = a[x]; } } if (n % 4 == 1) a[(n / 2) + 1] = (n / 2) + 1; for (int i = 1; i <= n; i++) printf("%d ", 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[1000000 + 10]; void dfs(int l, int r) { if (r - l + 1 < 4) return; a[l] = l + 1; a[l + 1] = r; a[r] = r - 1; a[r - 1] = l; dfs(l + 2, r - 2); } int main() { int xiaohao; int zheshixiaohao; int n; cin >> n; if (n == 1) { cout << "1"; } if (n == 2) { cout << "-1"; } if (n == 3) { cout << "-1"; } if (n == 4) { cout << "2 4 1 3"; } if (n == 5) { cout << "2 5 3 1 4"; } if (n == 6) { cout << "-1"; } if (n > 6) if (n % 4 == 2 || n % 4 == 3) cout << -1; else { for (int i = 1; i <= n; i++) a[i] = i; dfs(1, n); for (int i = 1; i < n; i++) cout << a[i] << " "; cout << a[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
//package round176; import java.io.ByteArrayInputStream; import java.io.IOException; import java.io.InputStream; import java.io.PrintWriter; import java.util.Arrays; import java.util.InputMismatchException; public class A { InputStream is; PrintWriter out; String INPUT = ""; void solve() { int n = ni(); if(n % 4 == 2 || n % 4 == 3){ out.println(-1); }else if(n % 4 == 0){ int[] a = new int[n]; for(int i = 0;i < n/2;i+=2){ a[i] = i+1; a[i+1] = n-i-1; a[n-1-i] = n-(i+1)-1; a[n-1-(i+1)] = i; } for(int i = 0;i < n;i++){ if(i > 0)out.print(" "); out.print(a[i]+1); } out.println(); }else{ int[] a = new int[n]; for(int i = 0;i < n/2;i+=2){ a[i] = i+1; a[i+1] = n-i-1; a[n-1-i] = n-(i+1)-1; a[n-1-(i+1)] = i; } a[n/2] = n/2; for(int i = 0;i < n;i++){ if(i > 0)out.print(" "); out.print(a[i]+1); } out.println(); } } void run() throws Exception { is = oj ? System.in : new ByteArrayInputStream(INPUT.getBytes()); out = new PrintWriter(System.out); long s = System.currentTimeMillis(); solve(); out.flush(); tr(System.currentTimeMillis()-s+"ms"); } public static void main(String[] args) throws Exception { new A().run(); } private byte[] inbuf = new byte[1024]; private int lenbuf = 0, ptrbuf = 0; private int readByte() { if(lenbuf == -1)throw new InputMismatchException(); if(ptrbuf >= lenbuf){ ptrbuf = 0; try { lenbuf = is.read(inbuf); } catch (IOException e) { throw new InputMismatchException(); } if(lenbuf <= 0)return -1; } return inbuf[ptrbuf++]; } private int ni() { int num = 0, b; boolean minus = false; while((b = readByte()) != -1 && !((b >= '0' && b <= '9') || b == '-')); if(b == '-'){ minus = true; b = readByte(); } while(true){ if(b >= '0' && b <= '9'){ num = num * 10 + (b - '0'); }else{ return minus ? -num : num; } b = readByte(); } } private boolean oj = System.getProperty("ONLINE_JUDGE") != null; private void tr(Object... o) { if(!oj)System.out.println(Arrays.deepToString(o)); } }
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.*; public class Main { public static void main(String[] args) throws Exception { long time = System.nanoTime(); int n = next(); if (n % 4 == 2 || n % 4 == 3) { out.println(-1); out.close(); return; } int[] x = new int[n]; for (int i = 0; 2*i + 1 < n; i += 2) { int a = i; int b = i + 1; int c = n - 1 - i; int d = n - 1 - i - 1; x[a] = d; x[d] = c; x[c] = b; x[b] = a; } if (n % 2 == 1) x[n/2] = n/2; for (int i = 0; i < n; i++) out.print((x[i] + 1) + " "); out.println(); // System.out.println((System.nanoTime() - time)* 1e-9); out.close(); } static PrintWriter out = new PrintWriter(System.out); static BufferedReader bufferedreader = new BufferedReader(new InputStreamReader(System.in)); static StringTokenizer in = new StringTokenizer(""); static String nextToken() throws Exception { if (!in.hasMoreTokens()) in = new StringTokenizer(bufferedreader.readLine()); return in.nextToken(); } static int next() throws Exception {return Integer.parseInt(nextToken());}; static int[] next(int n) throws Exception { int[] x = new int[n]; for (int i = 0; i < n; i++) x[i] = next(); return x; } static int[][] next(int n, int m) throws Exception { int[][] x = new int[n][]; for (int i = 0; i < n; i++) x[i] = next(m); return x; } static long nextl() throws Exception {return Long.parseLong(nextToken());}; static long[] nextl(int n) throws Exception { long[] x = new long[n]; for (int i = 0; i < n; i++) x[i] = nextl(); return x; } static long[][] nextl(int n, int m) throws Exception { long[][] x = new long[n][]; for (int i = 0; i < n; i++) x[i] = nextl(m); return x; } static double nextd() throws Exception {return Double.parseDouble(nextToken());}; static double[] nextd(int n) throws Exception { double[] x = new double[n]; for (int i = 0; i < n; i++) x[i] = nextd(); return x; } static double[][] nextd(int n, int m) throws Exception { double[][] x = new double[n][]; for (int i = 0; i < n; i++) x[i] = nextd(m); return x; } static String nextline() throws Exception { in = new StringTokenizer(""); return bufferedreader.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
import java.util.Scanner; public class c_176 { public static void main(String[] args) { Scanner sc = new Scanner(System.in); int n = sc.nextInt(); if ((n-1) % 4 == 1 || (n-1) % 4 == 2) { System.out.println(-1); return; } if (n % 2 == 0) { for (int i = 2; i <= n / 2; i += 2) { System.out.print(i + " " + ((n + 2) - i) + " "); } for (int i = n / 2 - 1; i >= 1; i -= 2) { System.out.print(i + " " + (n - i) + " "); } } else { for (int i = 2; i <= n / 2; i += 2) { System.out.print(i + " " + ((n + 2) - i) + " "); } System.out.print(n/2+1+" "); for (int i = n / 2 - 1; i >= 1; i -= 2) { System.out.print(i + " " + (n - i) + " "); } } } }
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
n=int(input()) if n%4>1:print(-1) else: ans=[i for i in range(1,n+1)] for i in range(0,n//2,2): ans[i]=i+2 ans[i+1]=n-i ans[n-i-1]=n-i-1 ans[n-i-2]=i+1 print(*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; int a[100001]; int main() { int i, j, k, m, n; cin >> n; if (n % 4 > 1) { cout << "-1" << endl; return 0; } int _front = 0, end_ = n - 1; list<int> L; for (i = 1; i <= n; i++) L.push_back(i); while (!L.empty()) { if (_front == end_) { a[end_] = L.front(); L.pop_back(); break; } int front1 = L.front(); L.pop_front(); int front2 = L.front(); L.pop_front(); int end1 = L.back(); L.pop_back(); int end2 = L.back(); L.pop_back(); a[_front] = front2; a[_front + 1] = end1; a[end_] = end2; a[end_ - 1] = front1; _front += 2; end_ -= 2; } for (i = 0; i < n; i++) cout << a[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 i, n; bool was[1000001]; vector<int> ans, a; int main() { cin >> n; for (i = 1; i <= n; i += 2) { if (i + 1 > n - i + 1) break; ans.push_back(i + 1); ans.push_back(n - i + 1); was[i + 1] = was[n - i + 1] = true; } for (i = 1; i <= n; i++) { if (was[i] == false) a.push_back(i); } if (a.size() % 2 == 1) { ans.push_back(a[a.size() / 2]); a.erase(a.begin() + (a.size() / 2)); } for (i = 0; i <= n; i++) { if ((a.size() / 2 - 1) - i < 0 || (a.size() / 2 - 1) + i + 1 > a.size()) break; ans.push_back(a[(a.size() / 2 - 1) - i]); ans.push_back(a[(a.size() / 2 - 1) + i + 1]); } for (int j = 0; j < n; j++) if (ans[ans[j] - 1] != n - j) cout << -1, exit(00); for (i = 1; i <= n; i++) cout << ans[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
#include <bits/stdc++.h> using namespace std; using ll = long long; const int N = 2e1 + 4; vector<int> circle; bool vis[N]; int parent[N]; int chk[N]; int color[N]; int tim[N]; int dis[N]; int position[N]; vector<int> adj[N]; vector<int> adj1[N]; vector<int> graph[N]; bool has_cycle; int maxdis, maxnode, Totnode, depth = 1; bool ok; queue<int> q; stack<int> stk; vector<int> solution; int indegree[N]; int go[N]; int to[N]; int main() { ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0); ; int t; int cas = 0; int n, m, i, j, cnt = 0, cnt1 = 0, cnt2 = 0, even = 0, odd = 0, len, k, r, l, z = 0, x = 0, y = 0, flag = 0, sum = 0; int a = 0, b = 0, c = 0, d = 0, p, q, ans = 0LL, rem, quot, zero = 0, fst = 0, null = 0, snd = 0, lst = 0, rone = 0, one = 0, pos = 0, neg = 0, mn = INT_MAX, mx = INT_MIN; char ch; int h1, h2, m1, m2, h; int velo1, velo2, ac1, ac2, tim; int node, edge, u, v, cost; int best, worst; double nd, ad, bd, xd; string str, str1 = "", str2 = "", str3 = "", strstore1 = "", strstore2 = ""; cin >> n; int arr[n + 4]; if (n % 4 <= 1) { x = 2; for (i = 1; i <= n / 2; i += 2, x += 2) { arr[i] = x; arr[n - i + 1] = n - x + 1; } x = n; for (i = 2; i <= n / 2; i += 2, x -= 2) { arr[i] = x; arr[n - i + 1] = n + 1 - x; } if (n % 4 == 1) { arr[n / 2 + 1] = n / 2 + 1; } for (i = 1; i <= n; i++) { cout << arr[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
#include <bits/stdc++.h> int a[100005]; int main() { int n, i; while (~scanf("%d", &n)) { if (n % 4 == 2 || n % 4 == 3) { printf("-1\n"); continue; } else { for (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 % 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> using namespace std; long a[100005]; int main(void) { 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; }
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; void solve() { if (n % 4 == 2 || n % 4 == 3) { cout << -1 << endl; return; } if (n == 1) { cout << 1 << endl; return; } cout << 2 << ' ' << n; for (int i = 1; i < n / 4; ++i) cout << ' ' << 2 * (i + 1) << ' ' << (n - 2 * i); if (n & 1) cout << ' ' << n / 2 + 1; for (int i = 0; i < (n / 4); ++i) cout << ' ' << (n / 2 - 1 - 2 * i) << ' ' << ((n + 1) / 2 + 2 * i + 1); cout << endl; } int main() { cin >> n; 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.BigInteger; import java.util.*; public class A { int[] doit(int n){ int[] a=new int[n]; int count=0; int cur=0; int x=0; int val=2; if(n==1)val=1; while(count!=n){ while(a[x]==0){ a[x]=val; val=n-x; x=a[x]-1; count++; } if(n-count==1) val=a[cur]+1; else val=a[cur]+2; while(cur<n&&a[cur]!=0)cur++; x=cur; } return a; } void solve() throws IOException { int n=nextInt(); if(n%4>1){ out.print(-1); } else{ int[] a=doit(n); for(int i=0;i<n;i++) out.print(a[i]+" "); } } public static void main(String[] args) throws IOException { new A().run(); } void run() throws IOException { reader = new BufferedReader(new InputStreamReader(System.in)); tokenizer = null; out = new PrintWriter(new OutputStreamWriter(System.out)); solve(); reader.close(); out.flush(); } BufferedReader reader; StringTokenizer tokenizer; PrintWriter out; 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 nextToken() throws IOException { while (tokenizer == null || !tokenizer.hasMoreTokens()) { tokenizer = new StringTokenizer(reader.readLine()); } return tokenizer.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
n = int(raw_input()) if n%4 in [0,1]: p = range(n) l = [(i,n-i-1) for i in xrange(n/2)] while l: (a,b),(c,d) = l.pop(),l.pop() p[a] = c p[c] = b p[b] = d p[d] = a print ' '.join(str(x+1) for x in p) else: print -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 n; int *a; void foo(int k, int i) { a[i] = k; a[k] = n - i + 1; a[n - k + 1] = i; a[n - i + 1] = n - k + 1; } void Zero() { for (int i = 1; i <= n; ++i) { a[i] = 0; } } void Print() { for (int i = 1; i <= n; ++i) { cout << a[i] << " "; } } int main() { cin >> n; if (n % 4 == 3 || n % 4 == 2) { cout << -1; return 0; } a = new int[n + 1]; Zero(); if (n % 4 == 0) { for (int j = 1; j <= n / 2;) { foo(j + 1, j); j += 2; } Print(); } if (n % 4 == 1) { for (int j = 1; j <= (n - 1) / 2;) { foo(j + 1, j); j += 2; } a[n / 2 + 1] = n / 2 + 1; Print(); } 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 = 300; const int dx[] = {-1, 1, 0, 0}; const int dy[] = {0, 0, -1, 1}; int n, p[110000]; int main() { cin >> n; if (n % 4 == 2 || n % 4 == 3) { cout << -1 << endl; return 0; } for (int i = n; i > n / 2 + 1; i -= 2) { p[i] = i - 1; p[i - 1] = n - i + 1; p[n - i + 2] = i; p[n - i + 1] = n - i + 2; } if (n % 4 == 1) p[n / 2 + 1] = n / 2 + 1; for (int i = 1; i < n; i++) cout << p[i] << " "; cout << p[n] << 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.util.Arrays; import java.util.Scanner; public class LuckyPermutation { public static void main(String[] args) { Scanner sc = new Scanner(System.in); int n = sc.nextInt(); sc.close(); int[] numeros = new int[n + 1]; Arrays.fill(numeros, 0); if (n%4 > 1){ System.out.println(-1); return; } int actual = 1; int cantidad = 0; if (n % 2 == 1) { numeros[n / 2 + 1] = n / 2 + 1; cantidad++; }else if(n == 1){ System.out.println(1); return; } while (cantidad < n) { while (numeros[actual] != 0) { actual++; } int c = actual; actual++; while (numeros[actual] != 0) { actual++; } int r = actual; numeros[c] = r; cantidad++; while (numeros[r] == 0) { numeros[r] = n - c + 1; c = r; r = numeros[r]; cantidad++; } } for (int i = 1; i < n + 1; i++) { System.out.print(numeros[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.Scanner; import java.io.OutputStream; import java.io.IOException; import java.io.PrintWriter; import java.io.InputStream; /** * Built using CHelper plug-in * Actual solution is at the top */ public class Main { public static void main(String[] args) { InputStream inputStream = System.in; OutputStream outputStream = System.out; Scanner in = new Scanner(inputStream); PrintWriter out = new PrintWriter(outputStream); TaskC solver = new TaskC(); solver.solve(1, in, out); out.close(); } } class TaskC { public void solve(int testNumber, Scanner in, PrintWriter out) { int n = in.nextInt(); if (n % 4 == 3 || n % 4 == 2) { out.print(-1); return; } int[] result = new int[n]; for (int i = 0; i < n / 2; i += 2) { result[n - i - 1 - 1] = i + 1; result[i] = i + 2; result[i + 1] = n - i; result[n - i - 1] = n - 1 - i; } if (n % 4 == 1) { result[n / 2] = n / 2 + 1; } for (int i = 0; i < n; i++) { out.print(result[i] + " "); } } }
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 oo = 0x3f3f3f3f; long long mod = 1e9 + 7; double eps = 1e-9; double pi = acos(-1); long long fastpower(long long b, long long p) { double ans = 1; while (p) { if (p % 2) { ans = (ans * b); } b = b * b; p /= 2; } return ans; } bool valid(int x, int y, int n, int m) { return (x >= 0 && y < m && x < n && y >= 0); } using namespace std; unordered_map<long long, int> cnt; int main() { ios_base::sync_with_stdio(false); cin.tie(NULL); ; long long n; cin >> n; vector<long long> ans(n + 1, 0); long long l = 1; long long r = n; for (int i = 0; i < (n / 2); i++) { if (i % 2 == 0) { ans[l] = r - 1; ans[r] = l + 1; } else { ans[l] = l - 1; ans[r] = r + 1; } l++; r--; } if (n % 2) { ans[(n + 1) / 2] = (n + 1) / 2; } for (int i = 1; i <= n; i++) { if (cnt.count(ans[i])) { cout << -1; return 0; } cnt[ans[i]] = 1; if (ans[ans[i]] != n - i + 1) { cout << -1; return 0; } } 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> int a[111111]; int main() { int n; scanf("%d", &n); if (n % 4 == 2 || n % 4 == 3) printf("-1\n"); else { int b = 1, e = n, mn = 1, mx = n; while (e - b + 1 >= 4) { a[b] = mn + 1; a[b + 1] = mx; a[e - 1] = mn; a[e] = mx - 1; b += 2; e -= 2; mn += 2; mx -= 2; } if (n % 4 == 1) a[b] = mn; 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; const int size = 100008; int p[size], n; void dfs_p(int i, int x) { if (x > 4) return; p[p[i]] = n - i + 1; dfs_p(p[i], x + 1); } int main() { int k, i, j, id; while (cin >> n) { memset(p, 0, sizeof(p)); if (n % 4 == 0 || n % 4 == 1) { k = n / 4; for (i = 1; i <= k; i++) { id = i * 2 - 1; p[id] = i * 2; dfs_p(id, 0); } if (n % 4 == 1) p[(n + 1) / 2] = (n + 1) / 2; printf("%d", p[1]); for (i = 2; i <= n; i++) printf(" %d", p[i]); puts(""); } 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
#include <bits/stdc++.h> using namespace std; const int oo = 2000000009; const int mx = 100005; int mustbe[mx], p[mx], n; void solve(int a, int b) { if (b - a < 0) return; if (b - a == 0) { p[a] = a; return; } p[a] = a + 1; p[a + 1] = b; p[b - 1] = a; p[b] = b - 1; solve(a + 2, b - 2); } int main() { scanf("%d", &n); if (n % 4 >= 2) { printf("-1"); return 0; } solve(1, n); for (int i = 1; i < (n + 1); ++i) printf("%d ", p[i]); fflush(stdout); for (int i = 1; i < (n + 1); ++i) assert(p[p[i]] == n - 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
#include <bits/stdc++.h> using namespace std; long long n, a[((long long)101 * 1000)], p[((long long)101 * 1000)]; int main() { ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0); cin >> n; if (n == 2 || n % 4 == 3 || n % 4 == 2) return cout << -1, 0; for (int i = 1, l = 1, r = n; i <= n - (n % 2); l += 2, r -= 2, i += 4) p[l] = l + 1, p[l + 1] = r, p[r] = r - 1, p[r - 1] = l; if (n % 2 == 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 java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.io.PrintWriter; import java.util.StringTokenizer; public class A { BufferedReader reader; StringTokenizer tokenizer; PrintWriter out; public void solve() throws IOException { int N = nextInt(); int[] ans = new int[N]; int remain = N; int start_num = 1; int end_num = N; int start_space = 0; while(remain >= 4){ ans[start_space] = start_num + 1; ans[start_space+1] = end_num; ans[N-1-start_space] = end_num - 1; ans[N-1-start_space-1] = start_num; start_num += 2; end_num -= 2; start_space += 2; remain -= 4; } if( remain == 1){ ans[start_space] = start_num; } else if( remain == 2){ out.println(-1); return; } else if( remain == 3){ out.println(-1); return; } for(int i = 0; i < N; i++){ out.print( ans[i] + " "); } } /** * @param args */ public static void main(String[] args) { new A().run(); } public void run() { try { reader = new BufferedReader(new InputStreamReader(System.in)); tokenizer = null; out = new PrintWriter(System.out); solve(); reader.close(); out.close(); } catch (Exception e) { e.printStackTrace(); System.exit(1); } } 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 nextToken() throws IOException { while (tokenizer == null || !tokenizer.hasMoreTokens()) { tokenizer = new StringTokenizer(reader.readLine()); } return tokenizer.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; int main() { ios::sync_with_stdio(0); cin.tie(0); int n; cin >> n; int a[n + 1]; if (n % 4 > 1) cout << -1 << endl; else { for (int i = 1; i < n / 2; i += 2) a[i] = i + 1, a[n - i + 1] = n - i, a[i + 1] = n - i + 1, a[n - i] = i; if (n % 4 == 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
import java.util.*; public class LuckPerm286A { public static void main(String[] args) { // Set up scanner Scanner sc = new Scanner(System.in); // System.out.println("Enter n"); int n = sc.nextInt(); if (n==1) { System.out.println(1); return; } if (n%4 == 2 || n%4 == 3) { System.out.println(-1); return; } int[] a = new int[n+1]; int numleft = n; int offset = 0; while (numleft >= 4) { a[1+offset] = 2+offset; a[2+offset] = n-offset; a[n-offset-1] = 1+offset; a[n-offset] = n-offset-1; numleft -= 4; offset+= 2; } if (numleft == 1) // One more in the middle, to itself { a[offset+1] = offset+1; } StringBuilder sb = new StringBuilder(); for (int i=1; i<=n; i++) { sb.append(a[i] + " "); } 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
#include <bits/stdc++.h> using namespace std; const double PI = 3.141592653589793238; template <typename T> std::ostream& operator<<(std::ostream& os, const std::vector<T>& vector) { for (size_t i = 0; i < vector.size(); ++i) { os << vector[i] << " "; } return os; } vector<int> FindHappyPermutaion(int n) { if (n == 1) { return vector<int>(2, 1); } else if (n % 4 == 2 || n % 4 == 3) { return vector<int>(2, -1); } else { vector<int> v(n + 1, 0); if (n % 4 == 0) { int k = n / 4; int l = n / 2; int r = l + 1; for (int i = 1; i <= k; ++i) { v[i] = l; v[l] = n - i + 1; v[n - i + 1] = r; v[r] = i; --l; ++r; } } else if (n % 4 == 1) { int k = n / 4; int l = n / 2; int r = l + 2; for (int i = 1; i <= k; ++i) { v[i] = l; v[l] = n - i + 1; v[n - i + 1] = r; v[r] = i; --l; ++r; } v[n / 2 + 1] = n / 2 + 1; } return v; } } void TestPermutation(const vector<int>& v) { int n = v.size() - 1; if (n != 1) { for (int i = 1; i <= n; ++i) { bool s = v[v[i]] == n - i + 1; cout << "n = " << n << ", i = " << i << ": " << s << "\n"; if (!s) { cerr << "\nFAIL" << "\nn = " << n << "\nn mod 4 = " << n % 4 << "\n"; throw std::runtime_error("FAIL"); } } } } void StressTest() { for (int n = 1; n <= 100000; ++n) { vector<int> v = FindHappyPermutaion(n); TestPermutation(v); } } int main() { std::ios_base::sync_with_stdio(false); int n; cin >> n; vector<int> v = FindHappyPermutaion(n); for (int i = 1; i < v.size(); ++i) { cout << v[i] << " "; } cout << "\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 MAXN = 100010 * 2; int p[MAXN]; int main() { int N; cin >> N; if (N % 4 > 1) puts("-1"); else { for (int i = 1; i * 2 < N; i += 2) { p[i] = i + 1; p[i + 1] = N + 1 - i; p[N + 1 - i] = N - i; p[N - i] = i; } if (N % 2) 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; template <class T> T _max(T a, T b) { return a > b ? a : b; } template <class T> T _min(T a, T b) { return a < b ? a : b; } int sgn(const double &x) { return (x > 1e-8) - (x < -1e-8); } int a[100010]; int main() { int n; cin >> n; if (n % 4 > 1) { puts("-1"); return 0; } if (n & 1) { int x = 2; int y = n; a[n / 2 + 1] = n / 2 + 1; for (int i = 1; i <= n / 2; i++) { if (i % 2 == 0) { a[i] = y; a[n + 1 - i] = n + 1 - y; y -= 2; } else { a[i] = x; a[n + 1 - i] = n + 1 - x; x += 2; } } } else { int x = 2; int y = n; for (int i = 1; i <= n / 2; i++) { if (i % 2 == 0) { a[i] = y; a[n + 1 - i] = n + 1 - y; y -= 2; } else { a[i] = x; a[n + 1 - i] = n + 1 - x; x += 2; } } } for (int i = 1; i <= n; i++) cout << a[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; inline bool EQ(double a, double b) { return fabs(a - b) < 1e-9; } const int INF = 1 << 29; inline int two(int n) { return 1 << n; } inline int test(int n, int b) { return (n >> b) & 1; } inline void set_bit(int& n, int b) { n |= two(b); } inline void unset_bit(int& n, int b) { n &= ~two(b); } inline int last_bit(int n) { return n & (-n); } inline int ones(int n) { int res = 0; while (n && ++res) n -= n & (-n); return res; } template <class T> void chmax(T& a, const T& b) { a = max(a, b); } template <class T> void chmin(T& a, const T& b) { a = min(a, b); } int main() { ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0); long long int n; cin >> n; if (n == 1) cout << "1" << endl; else if (n % 4 > 1) cout << "-1" << endl; else { for (long long int i = 2; i <= n / 2; i += 2) { cout << i << " " << n - i + 2 << " "; } if (n % 2 == 1) cout << (n + 1) / 2 << " "; for (int i = n / 2 - 1; i >= 1; i -= 2) cout << i << " " << n - 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(input()) if n % 4 > 1: print(-1) exit() a = [i for i in range(0, n+1)] for i in range(1, n//2+1, 2): p, q, r, s = i, i+1, n-i,n-i+1 a[p], a[q], a[r], a[s] = a[q], a[s], a[p], a[r] def check(arr): for i in range(1, n+1): k = arr[i] if arr[arr[k]] != n-k+1: return False return True # print(check(a)) print(*a[1:]) # Made By Mostafa_Khaled
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
/* * To change this template, choose Tools | Templates * and open the template in the editor. */ //package luckyperm; import java.util.Scanner; /** * * @author admin */ public class Main { /** * @param args the command line arguments */ public static void main(String[] args) { // TODO code application logic here Scanner scan=new Scanner(System.in); int n=scan.nextInt(),countN=0; int[] count=new int[n+1]; int[] p=new int[n+1]; int i=1,temp=n; if(n%4==2||n%4==3){ System.out.println("-1"); } else{ while(temp>1){ p[i]=i+1; p[i+1]=n-i+1; p[n-i+1]=n-i; p[n-i]=i; i+=2; temp-=4; } if(temp==1){ p[(n+1)/2]=(n+1)/2; } for(i=1;i<=n;i++){ System.out.print(p[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
#include <bits/stdc++.h> using namespace std; int main(void) { int n; cin >> n; if ((n - (n & 1)) % 4 != 0) cout << -1; else { set<int> disp; int v[n + 1], k = 1; memset(v, -1, sizeof v); for (int i = 1; i <= n; i++) disp.insert(i); if (n & 1) { v[(n + 1) / 2] = (n + 1) / 2; disp.erase((n + 1) / 2); } while (disp.size()) { if (v[k] != -1) { k++; continue; } v[k] = *((*disp.begin() == k) ? next(disp.begin()) : disp.begin()); v[v[k]] = n - k + 1; v[v[v[k]]] = n - v[k] + 1; v[v[v[v[k]]]] = n - v[v[k]] + 1; disp.erase(v[k]); disp.erase(v[v[k]]); disp.erase(v[v[v[k]]]); disp.erase(v[v[v[v[k]]]]); } for (int i = 1; i <= n; i++) cout << v[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; int a[1000001], n; int main() { cin >> n; if ((n / 2) % 2) { cout << -1 << endl; return 0; } int l = 2, r = n; for (int i = 1; i <= n / 2; i++) { if (i % 2) a[i] = l, a[n - i] = l - 1, l += 2; else a[i] = r, a[n - i + 2] = r - 1, r -= 2; } if (n % 2) 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
import java.util.Scanner; public class C { public static void main(String args[]){ Scanner in = new Scanner(System.in); int n=in.nextInt(); int a[]=new int[n+1]; boolean b[]=new boolean[n+1]; a[n-1]=1; b[n-1]=true; if(n%4==0 || n%4==1 ){ for(int j=0;j<n/2;j+=2){ a[j+1]=j+2; a[j+2]=n-j; a[n-j]=n-j-1; a[n-j-1]=j+1; } if(n%2==1) a[(n+1)/2]=(n+1)/2; for(int j=1;j<=n;j++) System.out.print(a[j]+" "); } 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
n = int(input()) p = [0] * n if n == 1: print(1) exit() for sh in range(n // 4): p[n - sh * 2 - 2] = n - sh * 2 p[sh * 2] = n - 1 - sh * 2 p[n - sh * 2 - 1] = 2 + sh * 2 p[sh * 2 + 1] = 1 + sh * 2 if n % 4 == 1: p[n // 2] = n // 2 + 1 if n % 4 == 2: print(-1) exit() if n % 4 == 3: print(-1) exit() print(" ".join([str(i) for i in p]))
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.InputStreamReader; import java.io.IOException; import java.io.BufferedReader; import java.io.OutputStream; import java.io.PrintWriter; import java.util.StringTokenizer; import java.io.InputStream; /** * Built using CHelper plug-in * Actual solution is at the top * @author ocelopilli */ 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); TaskA solver = new TaskA(); solver.solve(1, in, out); out.close(); } } class TaskA { int[] p; public void solve(int testNumber, InputReader in, PrintWriter out) { int n = in.nextInt(); if ( n%4==0 || n%4==1 ) { p = new int[ n+1 ]; int le = 1, ri = n; while ( le < ri ) { p[le] = ri - 1; p[le+1] = le; p[ri] = le+1; p[ri-1] = ri; le += 2; ri -= 2; } if ( le == ri ) p[le] = le; for (int i=1; i<=n; i++) { if ( i > 1 ) out.print(" "); out.print( p[i] ); } out.println(); } else out.println( -1 ); } } class InputReader { BufferedReader br; StringTokenizer st; public InputReader(InputStream in) { br = new BufferedReader(new InputStreamReader(in)); st = null; } public String next() { while (st==null || !st.hasMoreTokens()) { try { st = new StringTokenizer(br.readLine()); } catch (IOException e) { throw new RuntimeException(e); } } return st.nextToken(); } public int nextInt() { 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
import java.util.*; public class SinIsh { public static void main(String [] args){ Scanner in = new Scanner(System.in); int n=in.nextInt(); int array[]=new int[n]; boolean flag=false; if(n==1) System.out.print("1"); else if(n%4==3||n%4==2) System.out.print("-1"); else{ if(n%4==1) flag=true; for(int i=0;i<n/2;i+=2){ array[i]=i+2; array[i+1]=n-i; array[n-1-i]=n-1-i; array[n-2-i]=i+1; } StringBuilder str=new StringBuilder(); if(flag) array[(n-1)/2]=(n+1)/2; for(int i=0;i<n;i++){ str.append(array[i]+" "); } System.out.print(str); } } }
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.BufferedOutputStream; import java.io.BufferedReader; import java.io.IOException; import java.io.InputStream; import java.io.InputStreamReader; import java.io.PrintWriter; import java.util.StringTokenizer; public class ProblemA { public static void main(String[] args) throws IOException { ProblemA solver = new ProblemA(); solver.init(); solver.solve(); } private void init() { } private void solve() throws IOException { Reader in = new Reader(System.in); PrintWriter out = new PrintWriter(new BufferedOutputStream(System.out)); int n = in.nextInt(); int[] p = new int[n + 1]; int from = 1; int to = n; while (from <= to) { if (from == to) { p[from] = from; break; } else if (to - from <= 2) { p = null; break; } else { p[from] = from + 1; p[from + 1] = to; p[to] = to - 1; p[to - 1] = from; } from += 2; to -= 2; } if (p == null) out.println("-1"); else { for (int i = 1; i <= n; i++) { out.print(p[i] + " "); } out.println(); } out.flush(); out.close(); } private static class Reader { BufferedReader reader; StringTokenizer tokenizer; /** call this method to initialize reader for InputStream */ Reader(InputStream input) { reader = new BufferedReader( new InputStreamReader(input) ); tokenizer = new StringTokenizer(""); } /** get next word */ public String next() throws IOException { while ( ! tokenizer.hasMoreTokens() ) { //TODO add check for eof if necessary tokenizer = new StringTokenizer( reader.readLine() ); } return tokenizer.nextToken(); } public int nextInt() throws IOException { return Integer.parseInt( next() ); } public double nextDouble() throws IOException { return Double.parseDouble( next() ); } public long nextLong() throws IOException { 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
def main(): n = int(raw_input()) a = [0] * (n+1) if n % 4 > 1: print -1 return for y in xrange(n/4): x = y * 2 a[x+1] = x+2 a[x+2] = n-x a[n-x] = n-x-1 a[n-x-1] = x+1 if n % 4 == 1: a[(n+1)/2] = (n+1)/2 for x in a[1:]: print x, 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> int p[100001]; bool v[100001]; int main() { int n; scanf("%d", &n); int fill = 1; int c = 0; while (fill <= n) { while (p[fill] != 0 && fill <= n) fill++; if (fill > n) break; if (c == n - 1) { p[fill] = fill; if (n - fill + 1 == fill) c++; break; } p[fill] = fill + 1; v[fill + 1] = true; c++; int cur = fill; while (!(v[n - cur + 1] || p[p[cur]] > 0)) { if (p[p[cur]] == fill) fill++; p[p[cur]] = n - cur + 1; v[n - cur + 1] = true; cur = p[cur]; c++; } } if (c < n) printf("-1\n"); else { 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; char f(vector<int> a) { int n = a.size() - 1; for (int i = 1; i <= n; i++) if (a[a[i]] != n - i + 1) return false; return true; } int main() { int n; scanf("%d", &n); vector<int> a(n + 1, -1); a[1] = 2; a[n - 1] = 1; a[n] = n - 1; if (n % 2 == 0) { for (int i = 3; i <= n / 2; i += 2) a[i] = a[i - 2] + 2; for (int i = n - 3; i > n / 2; i -= 2) a[i] = a[i + 2] + 2; } else { for (int i = 3; i < n / 2 + n % 2; i += 2) a[i] = a[i - 2] + 2; a[n / 2 + 1] = n / 2 + 1; } for (int i = 1; i <= n; i++) { if (a[i] == -1) continue; if (a[a[i]] == -1) a[a[i]] = n - i + 1; if (a[a[i]] != n - i + 1) { printf("-1"); return 0; } } for (int i = 1; i <= n; i++) printf("%d ", 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> int p[100002]; int vis[100002]; int main() { int n; while (scanf("%d", &n) != EOF) { if (n % 4 != 0 && n % 4 != 1) { printf("-1\n"); continue; } else { memset(vis, 0, sizeof(vis)); for (int i = 1; i <= n / 2; i++) { if (vis[i] == 0) { p[i] = n - i; vis[i] = 1; p[n - i] = n - i + 1; vis[n - i] = 1; p[n - i + 1] = i + 1; vis[n - i + 1] = 1; p[i + 1] = i; vis[i + 1] = 1; } } 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; const int N = 100100; int p[N]; int main() { int n; cin >> n; int t = n % 4; if (t < 2) { if (t == 1) { p[n / 2 + 1] = n / 2 + 1; } for (int i = 1; 2 * i <= n; 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) cout << p[i] << " "; cout << endl; } else { cout << "-1" << 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 static java.lang.Math.*; import static java.math.BigInteger.*; import static java.util.Arrays.*; import static java.util.Collections.*; public class A { final static boolean autoflush = false; public A () { int N = sc.nextInt(); int [] res = new int [N]; switch(N%4) { case 1: res[(N-1)/2] = (N-1)/2; case 0: for (int i : rep(N/4)) { int a = 2*i, b = a+1; res[a] = b; res[b] = N-1-a; res[N-1-a] = N-1-b; res[N-1-b] = a; } for (int i : rep(N)) ++res[i]; exit(res); default: exit(-1); } } //////////////////////////////////////////////////////////////////////////////////// static int [] rep(int N) { return rep(0, N); } static int [] rep(int S, int T) { int [] res = new int [max(T-S, 0)]; for (int i = S; i < T; ++i) res[i-S] = i; return res; } static int [] req(int S, int T) { return rep(S, T+1); } //////////////////////////////////////////////////////////////////////////////////// /* Dear hacker, don't bother reading below this line, unless you want to help me debug my I/O routines :-) */ final static MyScanner sc = new MyScanner(); static class MyScanner { public String next() { newLine(); return line[index++]; } public char nextChar() { return next().charAt(0); } public int nextInt() { return Integer.parseInt(next()); } public long nextLong() { return Long.parseLong(next()); } public double nextDouble() { return Double.parseDouble(next()); } public String nextLine() { line = null; return readLine(); } public String [] nextStrings() { line = null; return readLine().split(" "); } public char [] nextChars() { return next ().toCharArray (); } public Integer [] nextInts() { String [] L = nextStrings(); Integer [] res = new Integer [L.length]; for (int i : rep(L.length)) res[i] = Integer.parseInt(L[i]); return res; } public Long [] nextLongs() { String [] L = nextStrings(); Long [] res = new Long [L.length]; for (int i : rep(L.length)) res[i] = Long.parseLong(L[i]); return res; } public Double [] nextDoubles() { String [] L = nextStrings(); Double [] res = new Double [L.length]; for (int i : rep(L.length)) res[i] = Double.parseDouble(L[i]); return res; } public String [] next (int N) { String [] res = new String [N]; for (int i : rep(N)) res[i] = sc.next(); return res; } public Integer [] nextInt (int N) { Integer [] res = new Integer [N]; for (int i : rep(N)) res[i] = sc.nextInt(); return res; } public Long [] nextLong (int N) { Long [] res = new Long [N]; for (int i : rep(N)) res[i] = sc.nextLong(); return res; } public Double [] nextDouble (int N) { Double [] res = new Double [N]; for (int i : rep(N)) res[i] = sc.nextDouble(); return res; } public String [][] nextStrings (int N) { String [][] res = new String [N][]; for (int i : rep(N)) res[i] = sc.nextStrings(); return res; } public Integer [][] nextInts (int N) { Integer [][] res = new Integer [N][]; for (int i : rep(N)) res[i] = sc.nextInts(); return res; } public Long [][] nextLongs (int N) { Long [][] res = new Long [N][]; for (int i : rep(N)) res[i] = sc.nextLongs(); return res; } public Double [][] nextDoubles (int N) { Double [][] res = new Double [N][]; for (int i : rep(N)) res[i] = sc.nextDoubles(); return res; } ////////////////////////////////////////////// private boolean eol() { return index == line.length; } private String readLine() { try { return r.readLine(); } catch (Exception e) { throw new Error (e); } } private final java.io.BufferedReader r; MyScanner () { this(new java.io.BufferedReader(new java.io.InputStreamReader(System.in))); } MyScanner (java.io.BufferedReader r) { try { this.r = r; while (!r.ready()) Thread.sleep(1); start(); } catch (Exception e) { throw new Error(e); } } private String [] line; private int index; private void newLine() { if (line == null || eol()) { line = readLine().split(" "); index = 0; } } } static void print (Object o, Object... a) { printDelim(" ", o, a); } static void cprint (Object o, Object... a) { printDelim("", o, a); } static void printDelim (String delim, Object o, Object... a) { pw.println(build(delim, o, a)); } static void exit (Object o, Object... a) { print(o, a); exit(); } static void exit() { pw.close(); System.out.flush(); System.err.println("------------------"); System.err.println("Time: " + ((millis() - t) / 1000.0)); System.exit(0); } static void NO() { throw new Error("NO!"); } //////////////////////////////////////////////////////////////////////////////////// static String build (String delim, Object o, Object... a) { StringBuilder b = new StringBuilder(); append(b, o, delim); for (Object p : a) append(b, p, delim); return b.toString().trim(); } static void append(StringBuilder b, Object o, String delim) { if (o.getClass().isArray()) { int L = java.lang.reflect.Array.getLength(o); for (int i : rep(L)) append(b, java.lang.reflect.Array.get(o, i), delim); } else if (o instanceof Iterable<?>) for (Object p : (Iterable<?>)o) append(b, p, delim); else b.append(delim).append(o); } //////////////////////////////////////////////////////////////////////////////////// static void statics() { abs(0); valueOf(0); asList(new Object [0]); reverseOrder(); } public static void main (String[] args) { new A(); exit(); } static void start() { t = millis(); } static java.io.PrintWriter pw = new java.io.PrintWriter(System.out, autoflush); static long t; static long millis() { return System.currentTimeMillis(); } }
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 A implements Runnable { static BufferedReader in; static PrintWriter out; static StringTokenizer st; static Random rnd; void solve() throws IOException { int n = nextInt(); if (n == 1) { out.println(1); } else if (n == 2) { out.println(-1); } else { int startFrom = n - 2; int[] p = new int[n]; solve(n, p, startFrom); if (n % 2 != 0) { p[n / 2] = (n / 2); } if (!check(n, p)) { out.println(-1); } else { for (int i = 0; i < n; i++) { out.print(p[i] + 1); out.print((i + 1) == n ? "\n" : " "); } } // rec(0, n, new int[n], new boolean[n]); } } private void rec(int step, int n, int[] h, boolean[] u) { if (step == n) { if (check(n, h)) { out.println(Arrays.toString(h)); out.flush(); } } else { for (int i = 0; i < n; i++) { if (!u[i]) { h[step] = i; u[i] = true; rec(step + 1, n, h, u); u[i] = false; } } } } private void solve(int n, int[] p, int ptr) { int needSum = n - 1; int l = 0, r = n - 1; int first = 1, last = n - 1; while (l + 1 < r - 1) { p[l] = first; p[l + 1] = last; p[r] = needSum - first; p[r - 1] = needSum - last; first += 2; last -= 2; l += 2; r -= 2; } } private boolean check(int n, int[] p) { for (int i = 0; i < n; i++) { if (p[p[i]] != n - i - 1) { // out.println(i + " " + p[i] + " " + p[p[i]] + " " + (n - i - // 1)); // out.flush(); return false; } } return true; } public static void main(String[] args) { new A().run(); } public void run() { try { final String className = this.getClass().getName().toLowerCase(); try { in = new BufferedReader(new FileReader(className + ".in")); out = new PrintWriter(new FileWriter(className + ".out")); // in = new BufferedReader(new FileReader("input.txt")); // out = new PrintWriter(new FileWriter("output.txt")); } catch (FileNotFoundException e) { in = new BufferedReader(new InputStreamReader(System.in)); out = new PrintWriter(System.out); } rnd = new Random(); solve(); out.close(); } catch (IOException e) { e.printStackTrace(); System.exit(42); } } String nextToken() throws IOException { while (st == null || !st.hasMoreTokens()) { String line = in.readLine(); if (line == null) return null; st = new StringTokenizer(line); } 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()); } }
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; inline bool EQ(double a, double b) { return fabs(a - b) < 1e-9; } template <typename T> inline T gcd(T a, T b) { if (b == 0) return a; else return gcd(b, a % b); } template <typename T> inline T lcm(T a, T b) { return (a * b) / gcd(a, b); } template <typename T> string toStr(T x) { stringstream st; st << x; string s; st >> s; return s; } template <class T> void splitStr(const string &s, vector<T> &out) { istringstream in(s); out.clear(); copy(istream_iterator<T>(in), istream_iterator<T>(), back_inserter(out)); } inline int two(int n) { return 1 << n; } inline int isOnBit(int n, int b) { return (n >> b) & 1; } inline void onBit(int &n, int b) { n |= two(b); } inline void offBit(int &n, int b) { n &= ~two(b); } inline int lastBit(int n) { return n & (-n); } inline int cntBit(int n) { int res = 0; while (n && ++res) n -= n & (-n); return res; } const int dx4[] = {-1, 0, 1, 0}; const int dy4[] = {0, 1, 0, -1}; const int dx8[] = {-1, 0, 1, 0, -1, -1, 1, 1}; const int dy8[] = {0, 1, 0, -1, -1, 1, -1, 1}; int n, ans[100000 + 5]; void solve() { if (n % 4 == 2 || n % 4 == 3) { puts("-1"); return; } else if (n == 1) { puts("1"); return; } int i = 1; while (i <= (n + 1) / 2) { if (i == (n + 1) / 2) { ans[i] = i; break; } ans[i] = i + 1; ans[n - i + 1] = (n + 1) - ans[i]; i++; ans[i] = n - i + 2; ans[n - i + 1] = i - 1; i++; } for (int i = (1), _b = (n); i <= _b; i++) printf("%d ", ans[i]); } int main() { scanf("%d", &n); 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
#include <bits/stdc++.h> using namespace std; int p[200000]; int pp[200000]; int a[200000]; int n; bool f() { for (int(i) = (0); (i) < (n); ++(i)) if (a[a[i + 1]] != n - i) return 0; return 1; } void ff(int id, int x) { if (a[id]) return; a[id] = x; ff(x, n - id + 1); } int main() { cin >> n; if (n == 1) { cout << 1 << endl; return 0; } if (n % 4 > 1) { cout << -1 << endl; return 0; } int id = 1; int x = 2, y = n; for (int(i) = (0); (i) < (n / 4); ++(i)) { a[id] = x; x += 2; id++; a[id] = y; y -= 2; id++; } id = n; x = 1; y = n - 1; for (int(i) = (0); (i) < (n / 4); ++(i)) { a[id] = y; y -= 2; id--; a[id] = x; x += 2; id--; } if (n % 2) a[(n + 1) / 2] = (n + 1) / 2; for (int(i) = (1); (i) < (n + 1); ++(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; long long k, a, b; int main() { long long n; cin >> n; long long ans[100000 + 1] = {}; if (n % 4 == 1) { ans[(n + 1) / 2] = (n + 1) / 2; long long mid = (n + 1) / 2; for (long long i = 1; i <= (n + 1) / 2; i++) { if (i % 2) { ans[mid - i] = i; ans[mid + i] = (n + 1 - i); } else { ans[mid - i] = (n + 1 - i); ans[mid + i] = i; } } for (long long i = 1; i <= n; i++) cout << ans[i] << " "; cout << endl; } else if ((n % 4) == 0) { long long mid = n / 2; for (long long i = 1; i <= (n) / 2; i++) { if (i % 2) { ans[mid - i + 1] = i; ans[n + 1 - mid + i - 1] = (n + 1 - i); } else { ans[mid - i + 1] = n + 1 - i; ans[n + 1 - mid + i - 1] = i; } } for (long long i = 1; i <= n; i++) cout << ans[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
#include <bits/stdc++.h> int m, n; int a[100050]; int main() { int i, j, k, x, y, z; scanf("%d", &n); if (n % 4 == 2 || n % 4 == 3) puts("-1"); else { j = n; i = 1; while (j >= i) { if (j == i) a[i] = i; else { a[i] = i + 1; a[i + 1] = j; a[j] = n - i; a[j - 1] = n + 1 - j; } i += 2; j -= 2; } for (i = 1; i <= n; i++) { printf("%d ", a[i]); } } getchar(); getchar(); }
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 = 1e6 + 5, Mod = 1e9 + 7; int main() { ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0); int n; cin >> n; if (n % 4 > 1) cout << "-1\n", exit(0); int Arr[n + 2]; if (n & 1) Arr[n / 2 + 1] = n / 2 + 1; for (int i = 1; i <= n / 2; i += 2) { Arr[i] = 2 + (i - 1); Arr[i + 1] = n - (i - 1); Arr[n - i + 1] = n - 1 - (i - 1); Arr[n - i] = 1 + (i - 1); } for (int i = 1; i <= n; i++) { if (i > 1) cout << " "; cout << Arr[i]; } cout << "\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; #pragma comment(linker, "/STACK:102400000,102400000") inline void read(int &x) { x = 0; char ch = getchar(); while (ch < '0') ch = getchar(); while (ch >= '0') { x = x * 10 + ch - 48; ch = getchar(); } } int a[100010], ans; bool f[100010]; int main() { int n; scanf("%d", &n); if (n == 1) puts("1"); else if (n == 2) puts("-1"); else if (n % 4 > 1) puts("-1"); else { if (n & 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 + 1 - i; a[n + 1 - i] = n - i; a[n - i] = i; } } for (int i = 1; i <= n; ++i) printf("%d%c", a[i], (i == n) ? '\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 p[100005]; bitset<100005> viz, ap; int main() { int n, sf; cin >> n; sf = n; if (n == 1) { cout << 1; return 0; } if (n % 4 == 2 || n % 4 == 3) { cout << -1; return 0; } for (int i = 1; i <= n; ++i) if (viz[i] == 0) { if (!(n % 4 == 1 && (i == n / 2 + 1))) { p[i] = i + 1; viz[i] = 1; p[i + 1] = sf; viz[i + 1] = 1; p[sf] = sf - 1; viz[sf] = 1; p[sf - 1] = i; viz[sf - 1] = 1; sf -= 2; } } for (int i = 1; i <= n; ++i) if (viz[i] == 0) { ap[n - i + 1] = 1; p[i] = n - i + 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
# Legends Always Come Up with Solution # Author: Manvir Singh import os import sys from io import BytesIO, IOBase from collections import deque def main(): n=int(input()) if n%4==2 or n%4==3: print(-1) else: a=deque(list(range(1,n+1))) ans=[0]*n for i in range(0,n//2,2): ans[-(i+2)]=a.popleft() ans[i]=a.popleft() ans[i+1]=a.pop() ans[-(i+1)]=a.pop() if a: ans[n//2]=a.pop() print(*ans) # region fastio BUFSIZE = 8192 class FastIO(IOBase): newlines = 0 def __init__(self, file): self._fd = file.fileno() self.buffer = BytesIO() self.writable = "x" in file.mode or "r" not in file.mode self.write = self.buffer.write if self.writable else None def read(self): while True: b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE)) if not b: break ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines = 0 return self.buffer.read() def readline(self): while self.newlines == 0: b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE)) self.newlines = b.count(b"\n") + (not b) ptr = self.buffer.tell() self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr) self.newlines -= 1 return self.buffer.readline() def flush(self): if self.writable: os.write(self._fd, self.buffer.getvalue()) self.buffer.truncate(0), self.buffer.seek(0) class IOWrapper(IOBase): def __init__(self, file): self.buffer = FastIO(file) self.flush = self.buffer.flush self.writable = self.buffer.writable self.write = lambda s: self.buffer.write(s.encode("ascii")) self.read = lambda: self.buffer.read().decode("ascii") self.readline = lambda: self.buffer.readline().decode("ascii") sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout) input = lambda: sys.stdin.readline().rstrip("\r\n") if __name__ == "__main__": main()
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.*; import java.math.BigInteger; import java.util.ArrayList; import java.util.Arrays; import java.util.List; import java.util.StringTokenizer; public class C implements Runnable { // leave empty to read from stdin/stdout private static final String TASK_NAME_FOR_IO = ""; // file names private static final String FILE_IN = TASK_NAME_FOR_IO + ".in"; private static final String FILE_OUT = TASK_NAME_FOR_IO + ".out"; BufferedReader in; PrintWriter out; StringTokenizer tokenizer = new StringTokenizer(""); public static void main(String[] args) { new Thread(new C()).start(); } boolean good(int n, int[] a) { for (int i = 0; i < n; i++) if (a[a[i] - 1] != n - i) { return false; } return true; } private void gen(int pos, int n, int[] used, int[] a, List<int[]> all) { if (pos == n) { if (good(n, a)) { all.add(a.clone()); } return; } for (int i = 0; i < n; i++) if (used[i] == 0) { used[i] = 1; a[pos] = i + 1; gen(pos + 1, n, used, a, all); used[i] = 0; } } private void solveNaive(int n) { List<int[]> all = new ArrayList<int[]>(); int[] used = new int[n]; int[] p = new int[n]; gen(0, n, used, p, all); System.out.println("N = " + n); for (int[] a : all) { System.out.println(Arrays.toString(a)); } } private void solve() throws IOException { /* for (int n = 5; n <= 12; n++) { solveNaive(n); solveGood(n); } */ int n = nextInt(); solveGood2(n); } private void solveGood2(int n) { int[] a = new int[n]; int mod4 = n % 4; if (n == 1) { out.print("1"); return; } if (mod4 > 1) { out.print("-1"); return; } int l = 0; int r = n - 1; int lo = 1; for (;;) { a[l] = n - 1; a[l + 1] = lo; a[r] = lo + 1; a[r - 1] = n; n -= 2; lo += 2; l += 2; r -= 2; if (l > r) { break; } if (l == r) { a[l] = n; break; } } for (int v : a) { out.print(v); out.print(' '); } } private void solveGood(int n) { System.out.println("N (GOOD) = " + n); int[] a = new int[n]; int mod4 = n % 4; if (n == 1) { System.out.println(Arrays.toString(new int[] {1})); return; } if (mod4 > 1) { System.out.println(-1); return; } int l = 0; int r = n - 1; int lo = 1; for (;;) { a[l] = n - 1; a[l + 1] = lo; a[r] = lo + 1; a[r - 1] = n; n -= 2; lo += 2; l += 2; r -= 2; if (l > r) { break; } if (l == r) { a[l] = n; break; } } System.out.println(Arrays.toString(a)); } public void run() { long timeStart = System.currentTimeMillis(); boolean fileIO = TASK_NAME_FOR_IO.length() > 0; try { if (fileIO) { in = new BufferedReader(new FileReader(FILE_IN)); out = new PrintWriter(new FileWriter(FILE_OUT)); } else { in = new BufferedReader(new InputStreamReader(System.in)); out = new PrintWriter(new OutputStreamWriter(System.out)); } solve(); in.close(); out.close(); } catch (IOException e) { throw new IllegalStateException(e); } long timeEnd = System.currentTimeMillis(); if (fileIO) { System.out.println("Time spent: " + (timeEnd - timeStart) + " ms"); } } private String nextToken() throws IOException { while (!tokenizer.hasMoreTokens()) { String line = in.readLine(); if (line == null) { return null; } tokenizer = new StringTokenizer(line); } return tokenizer.nextToken(); } private int nextInt() throws IOException { return Integer.parseInt(nextToken()); } private BigInteger nextBigInt() throws IOException { return new BigInteger(nextToken()); } private long nextLong() throws IOException { return Long.parseLong(nextToken()); } private 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> int p[100005]; int main() { int n; scanf("%d", &n); memset(p, 0, sizeof(p)); if (n == 1) { printf("1\n"); return 0; } if (n == 2 || n == 3 || n % 4 == 3 || n % 4 == 2) { printf("-1\n"); return 0; } if (n >= 4) { for (int i = 1; i <= n / 4; i++) { p[2 * i - 1] = 2 * i; p[2 * i] = n + 2 - 2 * i; p[n + 2 - 2 * i] = n + 1 - 2 * i; p[n + 1 - 2 * i] = 2 * i - 1; } if (n % 4 == 1) p[2 * (n / 4) + 1] = 2 * (n / 4) + 1; for (int i = 1; i <= n; 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
import java.util.*; public class Main { public static void main(String args[]) { (new Main()).solve(); } void solve() { Scanner cin = new Scanner(System.in); while( cin.hasNextInt() ) { int N = cin.nextInt(); if( N % 4 >= 2 ) { System.out.println(-1); continue; } int arr[] = new int[N]; int cur = 1; int rest = N; int L = 0; int R = N - 1; while( rest >= 4 ) { arr[L] = cur + 1; arr[L + 1] = N - cur + 1; arr[R - 1] = cur; arr[R] = N - cur; L += 2; R -= 2; rest -= 4; cur += 2; } if( rest == 1 ) { arr[L] = cur; } for(int i=0; i<N; ++i) { if( i > 0 ) { System.out.print(" "); } System.out.print(arr[i]); } System.out.println(); for(int i=0; i<N; ++i) { if( arr[ arr[i] - 1 ] != N - i ) { throw new RuntimeException("assertion fail: " + i); } } } } }
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 a[100010]; int main() { int i, j, k = 1, n, m; cin >> n; if (n % 4 == 2 || n % 4 == 3) { cout << "-1\n"; return 0; } for (i = 0; i < n / 4; i++) { int x = 2 * i + 1; a[x] = x + 1; a[n - x] = x; a[n + 1 - x] = n - x; a[x + 1] = n + 1 - x; } if (n % 2 != 0) a[n / 2 + 1] = n / 2 + 1; for (i = 1; i <= n; i++) cout << a[i] << " "; 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.io.*; import java.util.*; public class z3 { public static void wiw(long a,long b) { if (a<=b) {if (a==b) System.out.print(""+a+" "); else { System.out.print(""+(a+1)+" "+b+" "); wiw(a+2,b-2); System.out.print(""+(a)+" "+(b-1)+" "); }} } public static void main(String[] args) throws IOException { Scanner in = new Scanner(System.in); long n=in.nextLong(); if (((n%4)==2)||((n%4)==3)) System.out.println("-1"); else { wiw(1,n); } } }
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, i; int num1, num2, cnt; cin >> n; if (n == 1) { cout << 1 << endl; return 0; } if (n % 4 == 0) { cnt = n / 2; num1 = 2, num2 = n; while (num1 <= cnt) { cout << num1 << " " << num2 << " "; num1 += 2, num2 -= 2; } num1 -= 2, num2 += 2; num1--, num2--; while (num1 > 1) { cout << num1 << " " << num2 << " "; num1 -= 2, num2 += 2; } cout << num1 << " " << num2 << endl; } else if (n % 4 == 1) { cnt = n / 2; num1 = 2, num2 = n; while (num1 <= cnt) { cout << num1 << " " << num2 << " "; num1 += 2, num2 -= 2; } num1 -= 2, num2 += 2; cout << n / 2 + 1 << " "; num1--, num2--; while (num1 > 1) { cout << num1 << " " << num2 << " "; num1 -= 2, num2 += 2; } cout << num1 << " " << num2 << 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 output[100010]; int main() { int n; while (cin >> n) { if (n % 4 == 2 || n % 4 == 3) cout << -1 << endl; else { int front1 = 2, front2 = n, rear1 = n - 1, rear2 = 1; int i, count = 0; for (i = 1; count < n / 4; i += 2) { output[i] = front1; output[i + 1] = front2; output[n - i + 1] = rear1; output[n - i] = rear2; front1 += 2; front2 -= 2; rear1 -= 2; rear2 += 2; count++; } for (i = 1; i <= n; i++) { if (output[i]) cout << output[i] << " "; else cout << (n + 1) / 2 << " "; } cout << endl; } memset(output, 0, sizeof(output)); } 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.InputStreamReader; import java.io.IOException; import java.io.BufferedReader; import java.io.OutputStream; import java.io.PrintWriter; import java.util.StringTokenizer; import java.io.InputStream; /** * Built using CHelper plug-in * Actual solution is at the top * @author ocelopilli */ 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 { public void solve(int testNumber, InputReader in, PrintWriter out) { int n = in.nextInt(); int[] p = new int[ n + 1 ]; if ( n % 4 > 1 ) out.println( -1 ); else { p[ (n+1) / 2 ] = (n + 1) / 2; for (int le=1, ri=n; le<ri; le+=2, ri-=2) { p[ le ] = ri - 1; p[ ri-1 ] = ri; p[ ri ] = le + 1; p[ le + 1 ] = le; } for (int i=1; i<=n; i++) out.print( p[i]+" " ); } } } class InputReader { BufferedReader br; StringTokenizer st; public InputReader(InputStream in) { br = new BufferedReader(new InputStreamReader(in)); st = null; } public String next() { while (st==null || !st.hasMoreTokens()) { try { st = new StringTokenizer(br.readLine()); } catch (IOException e) { throw new RuntimeException(e); } } return st.nextToken(); } public int nextInt() { 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; long long Set(long long N, long long pos) { return N = N | (1 << pos); } long long reset(long long N, long long pos) { return N = N & ~(1 << pos); } bool check(long long N, long long pos) { return (bool)(N & (1 << pos)); } void CI(long long &_x) { scanf("%d", &_x); } void CO(long long &_x) { cout << _x; } template <typename T> void getarray(T a[], long long n) { for (long long i = 0; i < n; i++) cin >> a[i]; } template <typename T> void prLLIarray(T a[], long long n) { for (long long i = 0; i < n - 1; i++) cout << a[i] << " "; cout << a[n - 1] << endl; } const double EPS = 1e-9; const long long INF = 0x7f7f7f7f; long long dr8[8] = {1, -1, 0, 0, 1, -1, -1, 1}; long long dc8[8] = {0, 0, -1, 1, 1, 1, -1, -1}; long long dr4[4] = {0, 0, 1, -1}; long long dc4[4] = {-1, 1, 0, 0}; long long kn8r[8] = {1, 2, 2, 1, -1, -2, -2, -1}; long long kn8c[8] = {2, 1, -1, -2, -2, -1, 1, 2}; int ans[100005]; void rec(int b, int e) { if (b > e) return; if (b == e) { ans[b] = e; return; } ans[b] = b + 1; ans[b + 1] = e; ans[e] = e - 1; ans[e - 1] = b; rec(b + 2, e - 2); } int main() { int n; cin >> n; if (n % 4 == 2 || n % 4 == 3) { puts("-1"); return 0; } rec(1, n); for (int i = 1; i <= n; i++) cout << 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; long long n, i, f, m, a[211111], ans; vector<long long> v; double d; int main() { cin >> n; if (n == 1) cout << 1; else if (n % 4 == 2 || n % 4 == 3) cout << -1; else { for (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 % 2 == 1) a[n / 2] = n / 2; for (i = 0; i < n; i++) cout << 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
#include <bits/stdc++.h> using namespace std; int arr[100100]; int main() { int n; cin >> n; if (n == 1) { cout << "1" << endl; return 0; } memset(arr, 0, sizeof(arr)); bool f = true; int k = 0; if (n % 2) arr[n / 2 + 1] = n / 2 + 1; for (int i = 1; i <= n; i++) { if (arr[i] == 0 && k < n / 2) { k += 2; arr[i] = k; } arr[arr[i]] = n - i + 1; } for (int i = 1; i <= n && f; i++) if (arr[arr[i]] != n - i + 1) f = false; if (f) for (int i = 1; i <= n; i++) cout << arr[i] << " "; 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> int main() { int n, k = 1, i, j, a[100001]; scanf("%d", &n); if (n == 1) { printf("1"); return 0; } k = n / 2; for (i = 1, j = n; i < j; i++, j--) { if (i % 2 == 0) { a[i] = k; a[j] = n - k + 1; } else { a[i] = n - k + 1; a[j] = k; } k--; } if (i == j) a[i] = i; int f = 0; for (i = 1; i <= n; i++) if (a[a[i]] != n - i + 1) { f = 1; break; } if (f == 0) for (i = 1; i <= n; i++) printf("%d ", a[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; int v[100001]; int main() { int i, f, n; cin >> n; if (n % 4 == 2 || n % 4 == 3) cout << -1 << endl; else { if (n % 4 == 1) v[(n + 1) / 2] = (n + 1) / 2; i = 1; f = n; while (i < f) { v[i] = f - 1; v[f - 1] = f; v[f] = i + 1; v[i + 1] = i; i += 2; f -= 2; } for (i = 1; i <= n; i++) cout << 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
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9
#include <bits/stdc++.h> using namespace std; const int MAXN = 100005; int p[MAXN]; int ans[MAXN]; int l, r; void put_left(int x) { ans[l] = x; ++l; } void put_right(int x) { ans[r] = x; --r; } int main() { int n; scanf("%d", &n); if (n % 4 == 2 || n % 4 == 3) { puts("-1"); return 0; } l = 0, r = n - 1; for (int i = 0; i < n; ++i) { p[i] = i + 1; } while (r - l > 0) { int a = p[l], b = p[l + 1], c = p[r], d = p[r - 1]; put_left(b), put_left(c); put_right(d), put_right(a); } if (r == l) put_right(p[r]); for (int i = 0; i < n; ++i) printf("%d ", ans[i]); 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
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9
#include <bits/stdc++.h> using namespace std; int n, p[1010000]; int main() { cin >> n; if (n % 4 == 2 || n % 4 == 3) { cout << -1; exit(0); } if (n % 4 == 0) { for (int i = 1; i <= n / 2; i++) { if (i % 2 == 1) p[i] = i + 1, p[n + 1 - i] = n - i; else p[i] = n + 2 - i, p[n + 1 - i] = i - 1; } for (int i = 1; i <= n; i++) cout << p[i] << " "; } else { for (int i = 1; i <= n / 2; i++) { if (i % 2 == 1) p[i] = i + 1, p[n + 1 - i] = n - i; else p[i] = n + 2 - i, p[n + 1 - i] = i - 1; } p[n / 2 + 1] = n / 2 + 1; for (int i = 1; i <= n; i++) cout << p[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
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9
import java.util.Scanner; import java.io.OutputStream; import java.io.IOException; import java.io.PrintWriter; import java.io.InputStream; /** * Built using CHelper plug-in * Actual solution is at the top * @author Dzmitry Paulenka */ public class Main { public static void main(String[] args) { InputStream inputStream = System.in; OutputStream outputStream = System.out; Scanner in = new Scanner(inputStream); PrintWriter out = new PrintWriter(outputStream); TaskC solver = new TaskC(); solver.solve(1, in, out); out.close(); } } class TaskC { public void solve(int testNumber, Scanner in, PrintWriter out) { int n = in.nextInt(); if (n%4 > 1) { out.println(-1); return; } int a[] = new int[n+1]; for (int i = 2; i <= n/2; i += 2) { a[i-1] = i; a[n-(i-1)] = i-1; a[i] = n - i + 2; a[n - i + 2] = n - i + 1; } if (n % 2 != 0) { a[n/2+1] = n/2 + 1; } // System.out.println(check(a)); for (int i = 1; i < n; ++i) { out.print(a[i] + " "); } out.println(a[n]); } }
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
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#include <bits/stdc++.h> using namespace std; const int maxn = 2e5 + 100; const int mod = 1e9 + 7; int p[maxn]; bool mark[maxn]; int main() { ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0); int n; cin >> n; if (n % 4 > 1) return (cout << -1, 0); if (n % 4 == 1) p[n / 2 + 1] = n / 2 + 1; for (int i = 1; i <= n / 4; i++) { int s = 2 * i - 1; int f = n - 2 * i + 2; p[s] = s + 1, p[s + 1] = f, p[f] = f - 1, p[f - 1] = s; } for (int i = 0; i < n; i++) cout << p[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
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9
#include <bits/stdc++.h> #pragma comment(linker, "/STACK:256000000") using namespace std; const double infd = 2e+9; const int infi = INT_MAX; template <class T> inline T sqr(T x) { return x * x; } int main() { ios_base::sync_with_stdio(false); int n; cin >> n; if (n % 4 != 0 && n % 4 != 1) { cout << -1; return 0; } vector<int> p(n + 1, -1), c(n + 1, -1); if (n % 4 == 1) { int m = (n + 1) / 2; p[m] = m; c[m] = m; } int top = 1; while (top <= n) { int i, x; while (top <= n && p[top] != -1) top++; if (top > n) break; i = top++; while (top <= n && p[top] != -1) top++; if (top > n) break; x = top; for (int j = 0; j < 4; j++) { p[i] = x; i = n - i + 1; swap(i, x); } } 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
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import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; public class P286A_LuckyPermutation { public static void main(String[] args) throws IOException { BufferedReader in = new BufferedReader(new InputStreamReader(System.in)); int n = Integer.parseInt(in.readLine()); if (n % 4 > 1) { System.out.println(-1); return; } int k = n/4; for (int i=0; i<k; i++) { System.out.print((2*i+2) + " " + (n-2*i) + " "); } if (n % 4 == 1) { System.out.print((n+1)/2 + " "); } for (int i=k-1; i>=0; i--) { System.out.print((2*i+1) + " " + (n-2*i-1) + " "); } 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
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9
#include <bits/stdc++.h> using namespace std; const int MAXN = 1e5 + 5; int n, p[MAXN]; int main() { ios_base::sync_with_stdio(false); cin.tie(0); cin >> n; if (n % 4 == 2 || n % 4 == 3) { cout << -1; return 0; } int l = 1, r = n, div = n; while (div / 4) { p[l] = l + 1; p[l + 1] = r; p[r] = r - 1; p[r - 1] = l; l += 2; r -= 2; div -= 4; } if (n % 4) p[(n + 1) / 2] = (n + 1) / 2; for (int i = 1; i <= n; ++i) cout << p[i] << " "; }
CPP