Tree Traversal Lisp

gistfile1.lisp

;(load "1.lsp")

(setq tree '(1 (2 5) 6 (10 (14 (25 27) 40))))
(print tree)

(defun traverse-tree(tree depth)
	(if (atom tree)
		(progn (funcall func tree) (return-from traverse-tree))
	)
	(let ((list-len (length tree)))	
		;(format t "~%Depth is ~0$" depth)
		(unless (atom tree) 
			(mapcar 'traverse-tree tree (make-list list-len :initial-element (+ 1 depth)))
		)
		;(format t "~%Depth is ~0$" depth)
	)	
)



(defun flatten(list)
	(let ((leafs '()))		
		(defun collect-leaf(leaf)	
			(push leaf leafs)
		)
		(setq func 'collect-leaf)
		(traverse-tree tree 0)
		(nreverse leafs)
		(return-from flatten leafs)	
	)
)

(print (flatten tree))