#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2")

#include <iostream>

#ifdef NyaanLocal
#include "misc/timer.hpp"
#endif
using namespace std;

int N, Q;
char S[200200], a[4];
int A[200200];

void update(int k) {
  if (0 <= k and k + 2 < N) A[k] = S[k] + (S[k + 1] << 8) + (S[k + 2] << 16);
}
long long query(int l, int r) {
  int x = a[0] + (a[1] << 8) + (a[2] << 16);
  long long ans = 0, bns = 0;
  for (int i = l; i + 2 < r; i++) {
    bool cond = x == A[i];
    ans += cond ? i : 0;
    bns += cond ? 1 : 0;
  }
  return ans - bns * (l - 1);
}

int main() {
#ifdef NyaanLocal
  Timer timer;
#endif
  cin >> N >> Q >> S;
  for (int i = 0; i + 2 < N; i++) update(i);
  while (Q--) {
    int cmd;
    cin >> cmd;
    if (cmd == 1) {
      int k;
      char x;
      cin >> k >> x;
      k--;
      S[k] = x;
      update(k - 2), update(k - 1), update(k);
    } else {
      int l, r;
      cin >> l >> r >> a;
      --l;
      cout << query(l, r) << "\n";
    }
  }
#ifdef NyaanLocal
  cerr << timer() << endl;
#endif
}