xlib	avlcount

	lib read_pointer

	IF QDOS
		INCLUDE "avltree_def"
	ELSE
			INCLUDE "avltree.def"
	ENDIF


; ******************************************************************************
;
;	Count the	number of	nodes (elements) in	the AVL-tree
;
;	IN:	BHL = pointer to root of	AVL-tree
;	OUT:	DE =	number of	items in the AVL-tree
;
;	Registers	changed after return:
;	..BC..HL/IXIY	same
;	AF..DE../....	different
;
;	Design & programming by Gunther Strube,	Copyright	(C) InterLogic	1995
;
.avlcount			ld	de,0
.traverse_avltree	inc	b
				dec	b
				ret	z			; NULL - branch ended...
					inc	de				; count node...
					push	bc
					push	hl
					ld	a, avltree_left
					call	read_pointer
					call	traverse_avltree	; count left subtree
					pop	hl
					pop	bc
					push	bc
					push	hl
					ld	a,avltree_right
					call	read_pointer
					call	traverse_avltree
					pop	hl
					pop	bc
				ret