func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     string s;     cin >> s;     if (s.length() < 26) {       cout << -1 << endl;       return 0;     }     int j = -1;     for (int i = 0; i < s.length(); i++)       if (s[i] ==  a ) {         j = i + 1;         break;       }     if (j == -1) {       cout << -1 << endl;       return 0;     }     for (char c =  b ; c <=  z ; c++) {       bool f = 0;       for (int i = j; i < s.length(); i++) {         if (s[i] <= (char)(c - 1)) {           s[i] = c, j = i + 1, f = 1;           break;         }         if (s[i] == (char)(c)) {           j = i + 1, f = 1;           break;         }       }       if (f == 0) {         cout << -1 << endl;         return 0;       }     }     cout << s << endl;   }   