> t
(1 (2 () ()) (3 (4 () ()) (5 () ())))
> (memv? 2 t)
#t
> (memv? 20 t)
#f
> (memv? 2 t)
#t
> (memv? 2 t)
#t
> (memv? 20 t)
#f
> (memv-tree? 20 t)
#f
> (memv-tree? 2 t)
#t
> (and #t 23 5 1 4 2 #f)
#f
> (or #f #f #f #f 5)
5
> (or #f #f #f #f 5 #f #f)
5
> (memv-tree 2 t)
(2 () ())
> (memv-tree 1 t)
(1 (2 () ()) (3 (4 () ()) (5 () ())))
> (memv-tree 3 t)
(3 (4 () ()) (5 () ()))
> (memv-tree 20 t)
#f
> (path-tree 1 t)
(1)
> (path-tree 2 t)
(1 2)
> (path-tree 3 t)
(1 2 . #f)
> (path-tree 1 t)
(1)
> (path-tree 3 t)
(1 3)
> (path-tree 2 t)
(1 2)
> (path-tree 4 t)
(1 3 4)
> (path-tree 1 t)
(1)
> (path-tree 2 t)
(1 2)
> (path-tree 3 t)
(1 3)
> (path-tree 4 t)
(1 3 4)
> (path-tree 4 t)
(1 3 4)
> (path-tree 4 t)
(1 3 4)
> (path-tree 3 t)
(1 3)