//conditional compilation example
#include <stdio.h>
# define A 100
int
main (void)
{
#ifdef A
printf ("A is defined\n");
#endif
#ifndef A
printf ("A is not defined\n");
#else
printf("It is not true that A is undefined\n");
#endif
#if(A <= 200 && A >= 80)
printf ("A is between 80 and 200\n");
#elif (A > 200)
printf ("A is larger than 200\n");
#elif (A < 80)
printf ("A is smaller than 80\n");
#endif
return (0);
}
