//item.h - header file for item and key definition.#include <stdio.h>#ifndef _ITEM_H#define _ITEM_Htypedef struct {    int  num;    char name[30];} workerRec;typedef workerRec Item;typedef int Key;typedef int BOOL;#define EQ(key1, key2) (((key1) > (key2)) - ((key1) < (key2)))
// here can the user change the Equal parameter
// then when he want check EQ() with two strings or 
// anything other.
#define ZERO 0#define ZERO_SMALLER (-1)
#define ZERO_GREATER 1

#define ERROR() fprintf(stderr, "Error...\n");#endif //_ITEM_H