func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     int n, check = 0;     string x;     cin >> n >> x;     sort(x.begin(), x.end());     if (n == 1)       cout <<  YES ;     else {       for (int i = 0; i < x.size() - 1; i++) {         if (x[i] == x[i + 1]) {           check = 1;           break;         }       }       if (check == 1)         cout <<  YES ;       else         cout <<  NO ;     }     return 0;   }   