func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     ios_base::sync_with_stdio(false), cin.tie(nullptr);     string a, b, c =   ;     cin >> a >> b;     for (int i = 0; i < a.length(); i++) {       if (a[i] + 1 < b[i]) {         c += a[i] + 1;         for (int j = i + 1; j < a.length(); j++) c +=  z ;         break;       } else if (a[i] + 1 == b[i]) {         bool big = 0;         for (int j = i + 1; j < a.length(); j++) {           if (a[j] !=  z ) big = 1;         }         if (big) {           c += a[i];           for (int j = i + 1; j < a.length(); j++) c +=  z ;           break;         } else {           c += a[i] + 1;           for (int j = i + 1; j < a.length(); j++) c +=  a ;           break;         }       } else         c += a[i];     }     if (c != a && c != b)       cout << c;     else       cout <<  No such string ;     return 0;   }   