#include <bits/stdc++.h>   using namespace std;   int main() {     string s;     int n, m;     cin >> n >> m;     cin >> s;     for (int i = 0; i < m; i++) {       int l, r;       char c1, c2;       scanf( %d %d %c %c , &l, &r, &c1, &c2);       for (int j = l - 1; j < r; j++) {         if (s[j] == c1) {           s[j] = c2;         }       }     }     cout << s << endl;     cin >> n;     return 0;   }   