#include <stdio.h>

int main()
{
	int i, n;

	printf("Enter a positive integer (greater than 1) for primality testing: ");
	scanf("%d", &n);

	while (n < 2)
	{
		printf("Input number is less than 2\n");
		printf("Enter a positive integer (greater than 1) for primality testing: ");
		scanf("%d", &n);
	}

	for (i = 2; i <= (n + 1) / 2; i++)
		if ((n % i) == 0)
			break;

	if (((n % i) == 0) && (n != i))
		printf("%d is not a prime\n", n);
	else
		printf("%d is a prime\n", n);
}