Stepik_Task_11

//goo.gl/ssRBSi
#include <iostream>
#include <cmath>
#include <string>
using namespace std;

bool IsPrime(int n) {
    int div = 1;
    for (int i = 2; i <= sqrt(n); i++) {
        if (n % i == 0) {
            div = i;
            break;
        }
    }
    if (div == 1 || div == n) {
        return true;
    }
    return false;
}

int main() {
    int n;
    cin >> n;
    string result_answer = IsPrime(n) ? "YES" : "NO";
    cout << result_answer;
    return 0;
}