题解

#include<bits/stdc++.h>
using namespace std;
int main(){
    string rna1 ,rna2;
    double a ,b;
    cin >> a;
    cin >> rna1 >> rna2;
    for (int i = 0 ; i < rna1.size() ; i++)
        if (rna1[i] == rna2[i])  //如果碱基相同
            b++;
    if (b / rna1.size() >= a)  //相关性大小判断
        cout << "yes";
    else
        cout << "no";
    return 0;
}