#include<bits/stdc++.h>
namespace {
#pragma GCC diagnostic ignored "-Wunused-function"
#include<atcoder/all>
#pragma GCC diagnostic warning "-Wunused-function"
using namespace std;
using namespace atcoder;
#define rep(i,n) for(int i = 0; i < (int)(n); i++)
#define rrep(i,n) for(int i = (int)(n) - 1; i >= 0; i--)
#define all(x) begin(x), end(x)
#define rall(x) rbegin(x), rend(x)
template<class T> bool chmax(T& a, const T& b) { if (a < b) { a = b; return true; } else return false; }
template<class T> bool chmin(T& a, const T& b) { if (b < a) { a = b; return true; } else return false; }
using ll = long long;
using P = pair<int,int>;
using VI = vector<int>;
using VVI = vector<VI>;
using VL = vector<ll>;
using VVL = vector<VL>;

} int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  int n, q;
  cin >> n >> q;
  string s;
  cin >> s;
  auto f = [&](int i) {
    assert(0 <= i && i + 3 <= n);
    int v = 0;
    rep(j, 3) v = v * 26 + (s[i + j] - 'a');
    return v;
  };
  int k2 = bit_ceil(0U + n);
  struct S {
    int s0;
    ll s1;
  };
  vector<map<int, S>> d(2 * k2);
  auto add = [&](int i) {
    int x = f(i);
    for (int p = i + k2; p; p >>= 1) {
      auto& t = d[p][x];
      t.s0++;
      t.s1 += i;
    }
  };
  auto rmv = [&](int i) {
    int x = f(i);
    for (int p = i + k2; p; p >>= 1) {
      auto it = d[p].find(x);
      if (--it->second.s0 == 0) d[p].erase(it);  
      else it->second.s1 -= i;
    }
  };
  rep(i, n - 2) add(i);
  while (q--) {
    int op;
    cin >> op;
    if (op == 1) {
      int k;
      char x;
      cin >> k >> x;
      k--;
      rep(j, 3) {
        int i = k - j;
        if (0 <= i && i + 3 <= n) rmv(i);
      }
      s[k] = x;
      rep(j, 3) {
        int i = k - j;
        if (0 <= i && i + 3 <= n) add(i);
      }
    } else {
      int l, r;
      cin >> l >> r;
      l--, r -= 2;
      const int l0 = l;
      int v = 0;
      rep(_, 3) {
        char c;
        cin >> c;
        v = v * 26 + (c - 'a');
      }
      int s0 = 0;
      ll s1 = 0;
      l += k2, r += k2;
      while (l < r) {
        if (l & 1) {
          if (auto it = d[l].find(v); it != d[l].end()) s0 += it->second.s0, s1 += it->second.s1;
          l++;
        }
        if (r & 1) {
          r--;
          if (auto it = d[r].find(v); it != d[r].end()) s0 += it->second.s0, s1 += it->second.s1;
        }
        l >>= 1, r >>= 1;
      }
      ll ans = s1 - (ll)l0 * s0 + s0;
      cout << ans << '\n';
    }
  }
}