func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     int n;     cin >> n;     string myNumber;     cin >> myNumber;     int temp;     int fhalf = 0, shalf = 0;     for (int i = 0; i < n / 2; ++i) {       temp = myNumber[i] -  0 ;       if (temp != 4 && temp != 7) {         cout <<  NO ;         goto exit;       }       shalf += temp;     }     for (int i = n / 2; i < n; ++i) {       temp = myNumber[i] -  0 ;       if (temp != 4 && temp != 7) {         cout <<  NO ;         goto exit;       }       fhalf += temp;     }     if (fhalf == shalf)       cout <<  YES ;     else       cout <<  NO ;   exit:     return 0;   }   