🔷 C Program: Prime Number Check

#include<stdio.h>
int main( )
{
    int num, count = 0;
    printf("Enter the number:\n");
    scanf("%d", &num);

    if(num <= 1)
    {
        printf("%d is not a prime number:\n", num);
    }
    else
    {
        for(int i = 2; i <= num / 2; i++)
        {
            if(num % i == 0)
            {
                count++;
                break;
            }
        }

        if(count == 0)
        {
            printf("%d is a prime number:\n", num);
        }
        else
        {
            printf("%d is not a prime number:\n", num);
        }
    }
}
  

📘 Explanation:

This C program checks if a number is prime or not.

👉 A **prime number** is a number greater than 1 that is divisible only by 1 and itself.

🔸 First, the user enters a number.
🔸 If the number is less than or equal to 1, it's not prime.
🔸 If the number is greater than 1, the program checks if it has any divisors (from 2 to num/2).
🔸 If any divisor is found, `count` is incremented, and the loop breaks early for efficiency.
🔸 Finally, if no divisors are found (`count == 0`), it's a prime number.

🔍 Sample Output:

Enter the number:
7
7 is a prime number:

Enter the number:
10
10 is not a prime number:

Enter the number:
1
1 is not a prime number:
    

🏷️ Keywords:

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