func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     int a, b, c, d;     cin >> a >> b >> c >> d;     if (abs(a + c - b - d) > 1) {       cout <<  NO n ;     } else {       vector<int> v(a + b + c + d);       if (a + c > b + d) {         for (int i = 0; i < v.size(); i += 2) {           if (a) {             v[i] = 0;             a--;           } else {             v[i] = 2;             c--;           }         }         for (int i = 1; i < v.size(); i += 2) {           if (b) {             v[i] = 1;             b--;           } else {             v[i] = 3;             d--;           }         }       } else {         for (int i = 1; i < v.size(); i += 2) {           if (a) {             v[i] = 0;             a--;           } else {             v[i] = 2;             c--;           }         }         for (int i = 0; i < v.size(); i += 2) {           if (b) {             v[i] = 1;             b--;           } else {             v[i] = 3;             d--;           }         }       }       bool check = true;       for (int i = 0; i < (int)v.size() - 1; i++) {         if (abs(v[i] - v[i + 1]) != 1) {           check = false;           break;         }       }       if (a + c == b + d && check == false) {         for (int i = 0; i < (int)v.size() - 1; i += 2) {           swap(v[i], v[i + 1]);         }         check = true;         for (int i = 0; i < (int)v.size() - 1; i++) {           if (abs(v[i] - v[i + 1]) != 1) {             check = false;             break;           }         }       }       if (check) {         cout <<  YES n ;         for (int i : v) cout << i <<    ;         cout <<   n ;       } else         cout <<  NO ;     }     return 0;   }   