#include <bits/stdc++.h>
using namespace std;
#if __has_include("all.hpp")
#include "all.hpp"
#else
#include <atcoder/all>
#endif
using namespace atcoder;
int main(void){
    int n,q;
    cin>>n>>q;
    string s;
    cin>>s;
    while(q--){
        int op;
        cin>>op;
        if(op==1){
            int p;
            char c;
            cin>>p>>c;
            p--;
            s[p]=c;
        }else{
            string t;
            cin>>t;
            vector<int> z=z_algorithm(t+s);
            int flag=0;
            for(int i=t.size();i<z.size();i++){
                if(z[i]>=t.size()){
                    flag=1;
                    break;
                }
            }
            cout<<(flag?"Yes":"No")<<endl;
        }
    }
    return 0;
}