func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     int length;     cin >> length;     int query;     cin >> query;     string result;     cin >> result;     for (int i = 0; i < query; ++i) {       int left;       int right;       cin >> left >> right;       char which;       char what;       cin >> which >> what;       for (int j = left; j <= right; ++j)         if (result[j - 1] == which) result[j - 1] = what;     }     cout << result;   }   