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

#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using ll = long long;
#define rep(i,n) for (int i=0;i<(int)(n);i++)

struct S{
	array<ll,26> v1,v2;
	ll sm;
	S():sm(0){
		rep(i,26) v1[i]=v2[i]=0;
	}
};
S op(S a,S b){
	S c;
	ll smb=0;
	c.sm=a.sm+b.sm;
	rep(i,26) smb+=b.v1[i];
	rep(i,26){
		c.v1[i]=a.v1[i]+b.v1[i];
		c.v2[i]=a.v2[i]+b.v2[i];
		c.v2[i]+=a.v1[i]*(smb-b.v1[i]);
		c.sm+=a.v1[i]*b.v2[i];
		c.sm+=(a.v1[i]-1)*a.v1[i]/2*(smb-b.v1[i]);
	}
	return c;
}
S e(){
	return S();
}
S mk(int i){
	S s;
	s.v1[i]++;
	return s;
}

int main(){
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
	int n,q;
	string s;
	cin>>n>>s>>q;
	vector<S> ctoS(26);
	rep(i,26) ctoS[i]=mk(i);
	vector<S> v(n);
	rep(i,n) v[i]=ctoS[s[i]-'A'];
	atcoder::segtree<S,op,e> seg(v);
	rep(i,q){
		int t;
		cin>>t;
		if(t==1){
			int x;
			char c;
			cin>>x>>c;
			x--;
			seg.set(x,ctoS[c-'A']);
		}else{
			int l,r;
			cin>>l>>r;
			l--;
			cout<<seg.prod(l,r).sm<<"\n";
		}
	}
}