func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     string s;     char b, c;     int n, m;     int l, r;     cin >> n >> m;     cin >> s;     for (int j = 1; j <= m; j++) {       cin >> l >> r >> b >> c;       for (int i = l - 1; i < r; i++) {         if (s[i] == b) {           s[i] = c;         }       }     }     for (int i = 0; i < n; i++) cout << s[i];     return 0;   }   