c program for given number is prime number or not

#include<stdio.h>
void main()
{
    int num,i,count=0;
    printf("nEnter 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();
}