#include <stdio.h>
#include <atcoder/all>
#include <bits/stdc++.h>
using namespace std;
using namespace atcoder;
using mint = modint998244353;
#define rep(i,n) for (int i = 0; i < (n); ++i)
#define Inf32 1000000005
#define Inf64 1000000000000000001LL
long long cs[500][26*26*26],ss[500][26*26*26];
int B = 500;
string s;
short get(string t){
	short res = 0;
	rep(i,3){
		res *= 26;
		res += t[i] - 'a';
	}
	return res;
}

void deal(int pos,int add){
	if(pos < 2)return;
	if(pos >= s.size())return;
	string t = s.substr(pos-2,3);
	short cur = get(t);
	cs[pos/B][cur] += add;
	ss[pos/B][cur] += pos * add;
}

int main(){
	int n,q;
	cin>>n>>q;
	cin>>s;
	rep(i,n){
		deal(i,1);
	}
	rep(_,q){
		int t;
		cin>>t;
		if(t==1){
			int i;
			char c;
			cin>>i>>c;
			i--;
			rep(j,3){
				deal(i+j,-1);
			}
			s[i] = c;
			rep(j,3){
				deal(i+j,1);
			}
		}
		else{
			int l,r;
			cin>>l>>r;
			l--;
			string a;
			cin>>a;
			if(r-l < 3){
				cout<<0<<endl;
				continue;
			}
			l += 2;
			long long tl = l,tr = r;
			
			long long ans = 0,c = 0;
			short ta = get(a);
			while(l<r && l%B != 0){
				if(a == s.substr(l-2,3)){
					ans += l;
					c++;
				}
				l++;
			}
			while(l+B < r){
				ans += ss[l/B][ta];
				c += cs[l/B][ta];
				l += B;
			}
			while(l<r){
				if(a == s.substr(l-2,3)){
					ans += l;
					c++;
				}
				l++;
			}
			ans -= (tl-1) * c;
			cout<<ans<<endl;
		}
	}
}