#include <bits/stdc++.h>
using namespace std;

using ll = long long;

inline int encode(string& s, int start)
{
    return (s[start] - 'a') * 26 * 26 + (s[start + 1] - 'a') * 26 + (s[start + 2] - 'a');
}

int main()
{
    cin.tie(nullptr);
    ios::sync_with_stdio(false);


    const int ALL = 26 * 26 * 26;
        

    int N, Q;
    cin >> N >> Q;

    int k = (int)sqrt(N);
    if (k * k < N) k++;

    string state;
    cin >> state;
    vector<vector<ll>> sum(ALL, vector<ll>(k));
    vector<vector<ll>> count(ALL, vector<ll>(k));

    for (int i = 0; i < N - 2; i++)
    {
        int code = encode(state, i);
        int b = i / k;
        int rel = i - b * k;
        sum[code][b] += rel + 1;
        count[code][b]++;
    }

    for (int i = 0; i < Q; i++)
    {
        int q;
        cin >> q;
        if (q == 1)
        {
            int p;
            cin >> p;
            p--;
            char x;
            cin >> x;
            for (int j = p - 2; j <= p; j++)
            {
                if (j < 0 || j >= N - 2) continue;
                int c = encode(state, j);
                int b = j / k;
                int rel = j - b * k;
                sum[c][b] -= rel + 1;
                count[c][b]--;
            }

            state[p] = x;

            for (int j = p - 2; j <= p; j++)
            {
                if (j < 0 || j >= N - 2) continue;
                int c = encode(state, j);
                int b = j / k;
                int rel = j - b * k;
                sum[c][b] += rel + 1;
                count[c][b]++;
            }
        }
        else if (q == 2)
        {
            int l;
            cin >> l;
            l--;
            int r;
            cin >> r;
            string a;
            cin >> a;
            int code = encode(a, 0);
            int fl = l;

            long ans = 0;
            while (l < r - 2)
            {
                if (l % k == 0 && l + k <= r - 2)
                {
                    ans += (l - fl) * count[code][l / k] + sum[code][l / k];
                    l += k;
                }
                else
                {
                    if (encode(state, l) == code) ans += (l - fl) + 1;
                    l++;
                }
            }

            cout << ans << endl;
        }
    }
}