Prime

/**
    A program to determine whether a number is prime or not.
*/

#include <stdio.h>
#include <math.h>

int main()
{
    int n, i, j;
    bool is_prime;

    printf("Enter a number: ");
    scanf("%d", &n);

    is_prime = true;
    for(i=2, j=sqrt(n); i<=j; i++)
    {
        if(n % i == 0)
        {
            is_prime = false;
            break;
        }
    }

    if(is_prime == true) printf("Prime.");
    else printf("Not prime.");

    return 0;
}