// Example program to check if a number is a prime number
//
#include <stdio.h>

int main()
{
    int N, n, flag = 0;

    printf("Enter a positive integer: ");
    scanf("%d",&N);

    for(n=2; n<=N/2; ++n)
    {
        // condition for nonprime number
        if( N % n == 0 )
        {
            flag=1;
            break;
        }
    }

    if (flag==0)
        printf("%d is a prime number.",N);
    else
        printf("%d is not a prime number.",N);
    
    return 0;
}