Freeglut header declearetion problem

[abtahi tajwar]

As I'm learning freeglut, I have decleared these header files

#ifdef_APPLE_
#include<GLUT/glut.h>
#else
#include<GL/glut.h>
#endif 

But when I'm running the pre-downloaded source code, its working fine. But when I'm writing its and then trying to run then the compilar showing me error..
Could you guyz tell me whats the problem here?

[Muzibur Rahman]

what error? describe more details. Show the full source code as well as the errors.