MIT/GNU SCHEME PROGRAM FOR CREATING A BINARY TREE AND SEARCH AN ELEMENT IN A BINARY TREE

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(define (bstc l) (if (null? l) '() (list (car l) (bstc (lesser (cdr l) (car l))) (bstc (greater (cdr l) (car l))))))    ; FUNCTION FOR CREATING BINARY TREE
;Value: bstc



(define (greater l a) (if (null? l) '() (if (>= (car l) a) (cons (car l) (greater (cdr l) a)) (greater (cdr l) a))))   ; RETURNS ALL THE GREATER ELEMENTS IN LIST
;Value: greater




(define (lesser l a) (if (null? l) '() (if (< (car l) a) (cons (car l) (lesser (cdr l) a)) (lesser (cdr l) a))))   ; RETURNS ALL SMALLER ELEMENTS IN THE LIST
;Value: lesser



(bstc '(5 2 6))
;Value 14: (5 (2) (6))

(define (bstsearch l a) (if (null? l) #f (if (= (car l) a) #t (if (< a (car l)) (bstsearch (cadr l) a) (bstsearch (cddr l) a)))))  ; FUNCTION FOR SEARCHING..
;Value: bstsearch

(bstsearch (bstc '(5 23 34)) 3)
;Value: #f