Exercise 157: On some occasions lists are formed with cons and list. Reformulate the following lists using cons and empty exclusively

Exercise 157: On some occasions lists are formed with cons and list. Reformulate the following lists using cons and empty exclusively



;(cons "a" (list 0 false))
;
;(list (cons 1 (cons 13 empty)))
;
;(cons (list 1 (list 13 empty)) empty)
;
;(list empty empty (cons 1 empty))
;
;(cons "a" (cons (list 1) (list false empty)))


This exercise was pretty straight forward. I just built up the lists from scratch only using cons.

;1 Reformulate: (cons "a" (list 0 false))
(check-expect (cons "a" (cons 0 (cons false empty)))
              (cons "a" (list 0 false)))




;2 Reformulate: (list (cons 1 (cons 13 empty)))
(check-expect (list (cons 1 (cons 13 empty)))  
              (cons (cons 1 (cons 13 empty)) empty) )
    
          
;3 Reformulate (cons (list 1 (list 13 empty)) empty)
;  this one is a little more interesting - we are making 
;  a list of empty lists - easy enough to do though with 
;  a (cons empty empty)
(check-expect (cons (list 1 (list 13 empty)) empty)
              (cons (cons 1 (cons (cons 13 
                            (cons empty empty)) empty)) empty))


;4 Reformulate: (list empty empty (cons 1 empty))
(check-expect (list empty empty (cons 1 empty))
              (cons empty (cons empty (cons 
                                      (cons 1 empty) empty))))




;5 Reformulate: (cons "a" (cons (list 1) (list false empty)))
(check-expect (cons "a" (cons (list 1) (list false empty)))
              (list "a" (list 1) false empty))