题解 | 素数判定

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

bool issu(int k)
{
    for(int i = 2;i<=sqrt(k);i++)
    {
        if(k%i==0)
        {
            return false;
        }
    }
    return true;

}

int main()
{
    int k;
    while(cin>>k)
    {
        if(k<=0 || k == 1)
        {
            cout<<"no"<<endl;
            continue;
        }

        if(issu(k))
        {
            cout<<"yes"<<endl;
        }
        else {
        cout<<"no"<<endl;
        }
    }
    return 0;
}