P89124_en

/*
    Copyright (c) 2013    xerpi
*/

#include <iostream>
#include <vector>
#include <cmath>
using namespace std;

const int MAX_N = 10000001;

void build_sieve(vector<bool>& sieve);

int main()
{
    vector<bool> sieve(MAX_N);
    build_sieve(sieve);
    int n;
    while (cin >> n) {
        if (sieve[n])
            cout << n << " is prime" << endl;
        else
            cout << n << " is not prime" << endl;
    }

}


void build_sieve(vector<bool>& sieve)
{
    int size = sieve.size();
    sieve[0] = false;
    sieve[1] = false;
    for (int i = 2; i < size; ++i) {
        sieve[i] = true;
    }
    int limit = sqrt(size);
    for (int i = 2; i < limit; ++i) {
        if (sieve[i]) {
            for (int j = 2*i; j < size; j+=i) {
                sieve[j] = false;
            }
        }
    }
}