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