很简单

#include<iostream>
using namespace std;
int main(){
int n;
cin >> n;
bool flag=1;
for(int i=2;i<=n-1;i++ ){
if( n%i0 ){
flag = 0;
break;
}
}
if( n1 ) flag = 0;
if( flag == 1 )cout<<"Yes";
else cout<<"No";
return 0;
}