func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     ios::sync_with_stdio(false);     cin.tie(0), cout.tie(0);     string a, s;     cin >> a >> s;     vector<int> v(10, 0);     for (int i = 0; i < s.size(); i++) v[s[i] - 48]++;     int j = 9;     for (int i = 0; i < a.size(); i++) {       while (v[j] == 0 and j > 0) j--;       if (j > a[i] - 48) {         a[i] = j + 48;         v[j]--;       }     }     cout << a << endl;     return 0;   }   