Example: Prime Number or Not in C using For loop

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// Prime Number or Not in C using For loop
#include <stdio.h>

// It's the main function of the program
int main()
{
    int num;
    int is_prime = 0;

    // Step-1 Take input from the User
    printf("INPUT A NUMBER: ");
    scanf("%d", &num);

    // Step-2 Check if the input number is less than or equal to 1
    if (num <= 1)
        is_prime = 1;

    // Step-3 Use a loop to check whether the input number is prime or not
    for (int i = 2; i <= num / 2; i++)
    {
        // If the input number is divisible by i, then the input number is not a Prime
        if (num % i == 0)
        {
            is_prime = 1;
            break;
        }
    }

    // Step-4 If `is_prime == 0` INPUT number is prime
    // Final output of the program
    if (is_prime == 0)
        printf("%d IS A PRIME NUMBER.\n", num);
    else
        printf("%d IS NOT A PRIME NUMBER.\n", num);

    return 0;
}