这个程序的功能是什么?
#include <iostream>
using namespace std;
void main( )
{
int N;
cin >> N;
bool yes_no = true;
for (int n = 2; n < N/2; n++)
{
if (N % n == 0)
{
yes_no = false; break;
}
}
if (yes_no == true) cout << “Yes” << endl;
else cout << “No” << endl;
}