c program to find the number is prime or not

#include<stdio.h> 

#include<conio.h>

void main()

{

 int num, i, count = 0; 

 printf("Enter a number:");

 scanf("%d", &num); 

 for (i = 2; i <= num / 2; i++)

{

 if (num % i == 0)

{

   count++;

   break;

  }

 }

if (count == 0)

 printf("%d is a prime number", num);

else

 printf("%d is not a prime number", num);

 getch();

}