func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     long long a, b, c, d;     cin >> a >> b >> c >> d;     if (abs(c - d) > 1) {       cout <<  -1 ;       return 0;     }     if (max(c, d) > min(a, b)) {       cout <<  -1 ;       return 0;     }     if (a + b <= c + d) {       cout <<  -1 ;       return 0;     }     if (c == d) {       a--;       for (int i = 1; i <= a - c; i++) cout <<  4 ;       if (a == c - 1 && b > 1) {         cout <<  7 ;         b--;       }       for (int i = 1; i <= c; i++) cout <<  47 ;       for (int i = 1; i <= b - c; i++) cout <<  7 ;       if (a - c >= 0) cout <<  4 ;     }     if (c > d) {       for (int i = 1; i <= a - c; i++) cout <<  4 ;       for (int i = 1; i <= c; i++) cout <<  47 ;       for (int i = 1; i <= b - c; i++) cout <<  7 ;     }     if (c < d) {       if (b > 1) {         cout <<  7 ;         b--;       }       for (int i = 1; i < a - c; i++) cout <<  4 ;       for (int i = 1; i <= c; i++) cout <<  47 ;       for (int i = 1; i <= b - c; i++) cout <<  7 ;       cout <<  4 ;     }   }   