r5rs - Pairing 2 lists Scheme -


scheme/racket/r5rs

attempting make recursive procedure pairs 2 lists of same size. cant recursive call right. have , stuck.

(define (pairs list1 list2)   (if (or (null? list1) (null? list2))       '()         (cons (car list1) (car list2))         ))

test case: (pairs '(1 2 3) '(a b c)) desired output: ((1 . a) (2 . b) (3 . c)) current output: (1 . a)

you have cons current result recursive call of procedure, , that's it!

(define (pairs list1 list2)   (if (or (null? list1) (null? list2))       '()       (cons (cons (car list1) (car list2))             (pairs (cdr list1) (cdr list2)))))

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