题目

代码：

#include<iostream>
using namespace std;
int main(){
    ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
    string a,b;
    char g;
    int t,q,n,o,h;
    cin>>t;
    while(t--){
        cin>>n>>q;
        cin>>a>>b;
        if(a==b){
            cout<<"Yes\n";
        }
        else{
            cout<<"No\n";
        }
        for(int i=0;i<q;i++){
            cin>>o>>h>>g;
            if(o==1){
                b[h-1]=g;
            }
            if(o==0){
                a[h-1]=g;
            }
            if(a==b){
                cout<<"Yes\n";
            }
            else{
                cout<<"No\n";
            }
        }
    }
}

7~10TLE