Help!

#include <bits/stdc++.h>
using namespace std;

int main() {
    int s = 0, g;
    cin >> g;
    string s1, s2;
    cin >> s1 >> s2;
    for (int i = 0; i < s1.size(); i++){
        if (s1[i] == s2[i])
            s++;
    }
    cout << (s * 1.0 / s1.size() >= g ? "yes" : "no") << endl;
    return 0;
}