func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     string s;     cin >> s;     int alpha[26], kitta = 0;     for (int i = 0; i < 26; i++) alpha[i] = 0;     for (int i = 0; i < s.length(); i++) {       alpha[s[i] -  a ]++;       if (alpha[s[i] -  a ] == 1) kitta++;     }     if (kitta > 4 || kitta < 2) {       cout <<  No ;       return 0;     }     for (int i = 0; i < s.length(); i++) {       if (alpha[s[i] -  a ] > 1) {         kitta++;         alpha[s[i] -  a ] = 1;       }     }     if (kitta > 3)       cout <<  Yes ;     else       cout <<  No ;     return 0;   }   