Добре дошли в DrRacket, версия 7.0 [3m].
Език: R5RS [потребителски]; memory limit: 128 MB.
> (list? '())
#t
> (tree? t)
#t
> t
(1 (2 () ()) (3 (4 () ()) (5 () ())))
> (root-tree (left-tree t))
2
> (depth-tree t)
3
> (if t #t f)
> (member-tree 2 t)
(2 () ())
> (member-tree 3 t)
(3 (4 () ()) (5 () ()))
> (member-tree 3 t)
(3 (4 () ()) (5 () ()))
> (path-tree 2 t)
(2)
> (path-tree 2 t)
(1 2)
> (path-tree 3 t)
(1 2 . #f)
> (path-tree 2 t)
(1 2)
> (path-tree 3 t)
(1 3)
> 
(path-tree 10 t)
#f