#include <bits/stdc++.h>   using namespace std;   int main() {     int x;     while (cin >> x) {       map<char, int> p1;       string str, strr;       ;       bool l = 0;       int sum;       cin >> str;       for (int i = 0; i < str.size(); i++) {         p1[str[i]]++;       }       for (int i = 0; i < str.size(); i++) {         if (p1[str[i]] % x != 0) {           l = 1;           break;         }       }       if (l == 0) {         for (char i =  a ; i <=  z ; i++) {           sum = 0;           if (p1[i] > 0) {             sum = p1[i] / x;           }           while (sum--) {             strr += i;           }         }         while (x--) {           cout << strr;         }       } else         cout << -1;       cout << endl;     }   }   