Creating a tree in Scheme (Lisp)

hierarchical_data_structures_1.scm

; This creates a simple tree
(define tree-1 (cons (list 1 2) (list 3 4)))

; Quick linked list review
(list 1 2 3 4) ;is equivalent to:
(cons 1 (cons 2 (cons 3 (cons 4 ()))))

; And here is some interpreter action
; just for practice:

(define tree-1 (cons (list 1 2) (list 3 4)))
;Value: tree-1

;tree-1
;Value 11: ((1 2) 3 4)

(car tree-1)
;Value: (1 2)
; Using car on the tree doesn't return the first element
; We have hierarchy, hence the tree

(cdr tree-1)
;Value: (3 4)

(define linked-list-1 (list 1 2 3 4))
;Value: linked-list-1

(car linked-list-1)
;Value: 1