FIND PRIME NUMBER USING C PROGRAM

#include<stdio.h>
#include<conio.h>

void main( )

{
clrscr( ) ;
int num,count=0;

printf(" ENTER THE NUMBER TO CHECK IT IS PRIME OR NOT " ) ;

scanf("%d", &num);

for(int i=0;i<=num;i++)

{
   if(num%a= = 0)                                 //if statement used
       {     count++ ;  }
}

if(count= =2)                                       //if else selection statement used
{
   printf("Prime Number");
}
else
{
   printf("Not a  Prime Number");
}
getch( );

}