代码如下

#include<bits/stdc++.h>
using namespace std;
double n,ans;
string a,b;
int main(){	
	cin>>n>>a>>b;
	double l=a.length();
	for(int i=1;i<=l;i++){
		if(a[i]==b[i]){
			ans++;
		}
	}
	ans/=l;
	if(ans>=n){
		cout<<"yes";
	}
	else{
		cout<<"no";
	}
	return 0;
}