//------------------------------------------------------------------------------
class Header {
  Record*	 First; 		// byte offset of first record
  int		 NRecords;		// total number of records
  MainIndex* MainIndexRoot;	// pointer to root of main index tree
  Index2*	 Index2Root;	// pointer to root of 2nd index tree
}; // Header
//------------------------------------------------------------------------------
class Record {
  int		ID;		// unique record ID
  char*	Name;		// Last Name
  char* 	OtherInfo;	// stuff

  void MarkRecord ( Record* Rec );
	// THIS IS ALREADY WRITTEN
	// marks a record as deleted

  void InsertRecord ( Record* NewRec, int& success );
	// YOU WRITE THIS
// add a new record to the file
// NewRec already contains all required data
// success = byte offset of the new record 
//           or ?1 if unsuccessful

  int FindRecord ( int ID );
	// YOU WRITE THIS TOO ? used by DELETE
	// finds record; 
// returns byte offset of found record or ?1 if not found

  void DeleteRecord ( int ID, int& success );
	// YOU WRITE THIS TOO
	// deletes record from file
	// success = -1 if delete was unsuccessful
	//            0 if all went well
	//            N indicating nature of error
}; // Record
//------------------------------------------------------------------------------

class MainIndex {
  int 	 Key;		// same as ID from Record
  int 	 Offset;	// byte offset of record in file
  MainIndex* Left;	// left sub-tree
  MainIndex* Right;	// right sub-tree

 void InsertMainIndex ( MainIndex* NewEntry, int& success );
// ASSUME THIS CODE IS WRITTEN
// inserts new index entry into tree
// success = byte offset of the new record or ?1 if unsuccessful           

  MainIndex* FindMainIndex ( int ID );
// ASSUME THIS CODE IS WRITTEN
	// finds main index entry; 
// returns pointer to index enrty or ?1 if not found

  void DeleteMainIndex ( int ID, int& success );
// ASSUME THIS CODE IS WRITTEN
	// deletes main index entry from tree
	// success = -1 if delete was unsuccessful
	//            0 if all went well
	//            N indicating nature of error
}; // MainIndex
//------------------------------------------------------------------------------
class Index2 {
  char* 	 Key2;		// same as Name from Record
  MainInex* List[100];		// list of pointers to MainIndex
	// one for each entry in main index that has this name
  int		 ListN;		// count of pointers in previous list
  Index2*	 Left;		// left sub-tree
  Index2*	 Right;		// right sub-tree

  void InsertIndex2 ( Index2* NewEntry, int& success );
// ASSUME THIS CODE IS WRITTEN
// inserts new index entry into tree
// success = byte offset of the new record 
//           or ?1 if unsuccessful

  Index2* FindIndex2 ( int ID );
// ASSUME THIS CODE IS WRITTEN
	// finds Secondary index entry; 
// returns pointer to index enrty or ?1 if not found

  void DeleteIndex2 ( int ID, int& success );
// ASSUME THIS CODE IS WRITTEN
	// deletes Secondary index entry from tree
	// success = -1 if delete was unsuccessful
	//            0 if all went well
	//            N indicating nature of error
}; // Index2