func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     int n;     cin >> n;     string a;     cin >> a;     if (a.size() > 26) {       cout <<  -1 n ;     } else {       int count = 0;       int hash[26] = {0};       for (int i = 0; i < a.size(); i++) {         if (hash[a[i] - 97])           count++;         else           hash[a[i] - 97]++;       }       cout << count <<   n ;     }   }   