/* -*- coding: utf-8 -*-
 *
 * 3637.cc:  No.3637 PANDORA - yukicoder
 */

#include<cstdio>
#include<set>
#include<algorithm>

using namespace std;

/* constant */

const int MAX_N = 200000;
const int MAX_L = 10;

/* typedef */

using si = set<int>;

/* global variables */

char s[MAX_N + 4];
si pvs[26];

/* subroutines */

bool check(char t[]) {
  int u = 0;
  for (int i = 0; t[i]; i++) {
    auto &pvi = pvs[t[i] - 'a'];
    auto sit = pvi.lower_bound(u);
    if (sit == pvi.end()) return false;
    u = *sit + 1;
  }
  return true;
}

/* main */

int main() {
  int n, qn;
  scanf("%d%d%s", &n, &qn, s);

  for (int i = 0; i < n; i++) pvs[s[i] - 'a'].insert(i);

  while (qn--) {
    int op;
    scanf("%d", &op);

    if (op == 1) {
      int i;
      char t[MAX_L + 4];
      scanf("%d%s", &i, t), i--;

      pvs[s[i] - 'a'].erase(i);
      s[i] = t[0];
      pvs[s[i] - 'a'].insert(i);
    }
    else {
      char t[MAX_L + 4];
      scanf("%s", t);

      if (check(t)) puts("Yes");
      else puts("No");
    }
  }
  
  return 0;
}