#include<bits/stdc++.h>
#include<atcoder/all>
using namespace std;
using namespace atcoder;
typedef long long int ll;
typedef long double ld;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef vector<vl> vvl;
typedef vector<vvl> vvvl;
typedef vector<vvvl> vvvvl;
typedef vector<bool> vb;
typedef vector<vb> vvb;
typedef vector<vvb> vvvb;
typedef vector<vvvb> vvvvb;
typedef pair<ll,ll> pl;
typedef pair<ll,pl> ppl;
typedef pair<ll,ppl> pppl;
typedef pair<ll,pppl> pppppl;
#define rep(i,a,b) for(int i=(a);i<(b);i++)
#define rrep(i,a,b) for(int i=(b)-1;i>=(a);i--)
#define all(a) begin(a),end(a)
#define sz(a) (int)(a).size()
#define F first
#define S second
#define bs(A,x) binary_search(all(A),x)
#define lb(A,x) (ll)(lower_bound(all(A),x)-A.begin())
#define ub(A,x) (ll)(upper_bound(all(A),x)-A.begin())
#define cou(A,x) (ll)(upper_bound(all(A),x)-lower_bound(all(A),x))
template<typename T>using min_priority_queue=priority_queue<T,vector<T>,greater<T>>;
template<class T>bool chmax(T&a,T b){if(a<b){a=b;return 1;}return 0;}
template<class T>bool chmin(T&a,T b){if(b<a){a=b;return 1;}return 0;}
//*
using mint=modint998244353;
const ll mod=998244353;
//*/
/*
using mint=modint1000000007;
const ll mod=1000000007;
//*/
//using mint=modint;
//*
typedef vector<mint> vm;
typedef vector<vm> vvm;
typedef vector<vvm> vvvm;
typedef vector<vvvm> vvvvm;
ostream&operator<<(ostream&os,mint a){os<<a.val();return os;}
istream&operator>>(istream&is,mint&a){int x;is>>x;a=mint(x);return is;}
//*/
template<typename T1,typename T2>ostream&operator<<(ostream&os,pair<T1,T2>p){os<<p.F<<" "<<p.S;return os;}
template<typename T1,typename T2>istream&operator>>(istream&is,pair<T1,T2>&p){is>>p.F>>p.S;return is;}
template<typename T>ostream&operator<<(ostream&os,vector<T>v){rep(i,0,sz(v))os<<v[i]<<(i+1!=sz(v)?" ":"");return os;}
template<typename T>istream&operator>>(istream&is,vector<T>&v){for(T&in:v)is>>in;return is;}
ll op(ll a,ll b){return min(a,b);}
ll e(){return 1e18;}
int main(){
  cin.tie(0)->sync_with_stdio(0);
  cin.exceptions(cin.failbit);
  ll N,Q;cin>>N>>Q;
  string S;cin>>S;
  const int bs=450;
  vector<int>A(bs*bs);
  vector<vector<int>>T(26*26*26,vector<int>(bs));
  vector<vector<int>>U(26*26*26,vector<int>(bs));
  auto f=[](char a,char b,char c){
  	return (a-'a')+26*(b-'a')+26*26*(c-'a');
  };
  rep(i,0,N-2){
  	int x=f(S[i],S[i+1],S[i+2]);
  	A[i]=x;
  	T[x][i/bs]++;
  	U[x][i/bs]+=i;
  }
  while(Q--){
  	ll t;cin>>t;
  	if(t==1){
  		ll i;char c;cin>>i>>c;i--;
  		if(i<N-2)T[A[i]][i/bs]--,U[A[i]][i/bs]-=i;
  		if(0<i&&i<N-1)T[A[i-1]][(i-1)/bs]--,U[A[i-1]][(i-1)/bs]-=i-1;
  		if(1<i)T[A[i-2]][(i-2)/bs]--,U[A[i-2]][(i-2)/bs]-=i-2;
  		S[i]=c;
  		if(i<N-2)A[i]=f(S[i],S[i+1],S[i+2]),T[A[i]][i/bs]++,U[A[i]][i/bs]+=i;
  		if(0<i&&i<N-1)A[i-1]=f(S[i-1],S[i],S[i+1]),T[A[i-1]][(i-1)/bs]++,U[A[i-1]][(i-1)/bs]+=i-1;
  		if(1<i)A[i-2]=f(S[i-2],S[i-1],S[i]),T[A[i-2]][(i-2)/bs]++,U[A[i-2]][(i-2)/bs]+=i-2;
  	}
  	else{
  		int l,r;cin>>l>>r;l--;r-=2;
  		int i=l;
  		string s;cin>>s;
  		if(l>=r){cout<<0<<endl;continue;}
  		int x=f(s[0],s[1],s[2]);
  		ll t=0,u=0;
  		while(l<r&&l%bs){
  			if(A[l]==x)t++,u+=l;
  			l++;
  		}
  		while(l<r&&r%bs){
  			r--;
  			if(A[r]==x)t++,u+=r;
  		}
  		while(l<r){
  			t+=T[x][l/bs];
  			u+=U[x][l/bs];
  			l+=bs;
  		}
  		cout<<u-t*(i-1)<<endl;
  	}
  }
  return 0;
}