/* *  The RID class defines record identifier objects. A record identifier *  uniquely identifies a record within a given file, based on the record's *  page number in the file and slot number within that page. */#ifndef RID_H#define RID_H#include "RM.h"class RID {private:	PageNum pageNum;	SlotNum slotNum;	bool bValid; /* Is RID a valid record identifier? */public:	  /* Constructs a new RID object */	  RID ();	  /* Constructs a new RID object from the given page and slot	   * numbers */	  RID (PageNum pageNum, SlotNum slotNum);	/* Sets page number to the record indentifier's page number */	RC GetPageNum (PageNum &pageNum) const;	/* Sets slot number to the record indentifier's slot number */	RC GetSlotNum (SlotNum &slotNum) const;	void PrintRid () const;};#endif