Prime Number program in C

Prime Number program in C
A prime number is a positive integer that is divisible only by 1 and itself. For example: 2, 3, 5, 7, 11, 13, 17, 19 etc.

// C program to check if a number is prime or not

#include <stdio.h>
#include <stdbool.h>

bool checkPrime(int num)
    int i;
    bool flag = false;

    // 0 and 1 are not prime numbers
    if (num == 0 || num == 1)
        flag = true;

    for (i = 2; i <= num / 2; ++i)

        // if num is divisible by i, then n is not prime
        if (num % i == 0)
            flag = true;
    return flag;

int main()
    int num;
    printf(" Enter the number:");
    scanf("%d", &num);
    if (checkPrime(num) == false)
        printf("%d is a Prime Number\n", num);
        printf("%d is not a Prime Number\n", num);

    return 0;
$ gcc prime.c
$ ./a.out
Enter the number:2
2 is a Prime Number
$ ./a.out
Enter the number:14
14 is not a Prime Number
$ ./a.out
Enter the number:56
56 is not a Prime Number
$ ./a.out
Enter the number:17
17 is a Prime Number

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