Check whether a number is a Prime number or not with C.

#include <stdio.h>

int main()
{
    int i, num, isPrime=0;
 

    printf("Enter any number to check prime: ");
    scanf("%d", &num);

    for (i = 2; i <= num / 2; i++)
    {
        if (num % i == 0)
        {
            isPrime = 1;
            break;
        }
    }
    if (isPrime == 0 && num > 1)
    {
        printf("%d is prime number", num);
    }
    else
    {
        printf("%d is composite number", num);
    }
    return 0;
}

Output:-


Enter any number to check prime : 89
89 is prime number