PROGRAM TO FIND WHETHER THE NUMBER IS PRIME OR NOT

#include<stdio.h>
#include<conio.h>
void main()
{
int num,count,halfnum,flag=0;
clrscr();
printf("\n enter a number :\n");
scanf("%d",&num);
halfnum=num/2;
for(count=2;count<=halfnum;count++)
if(num%count==0)
{
flag=1;
break;
}
if(flag==0)
printf("\n number is prime");
else
printf("\n number is not prime");
getch();

}