注意sum要强制类型转换double
否则答案错误

C++ 代码

#include<bits/stdc++.h>

using namespace std;

int main()
{
    string a,b;
    int sum=0;
    double t;
    cin>>t>>a>>b;
    for(int i=0;i < a.size(); i++)
        if(a[i] == b[i])
            sum++;
    double n = (double)sum / a.size();
    n >= t ? cout<<"yes" : cout<<"no";
}