; A list-of-num is either
;  - empty
;  - (make-bigger-list num list-of-num)
(define-struct bigger-list (first rest))

; aq-weight : list-of-num -> num
(define (aq-weight l)
  (cond
    [(empty? l) 0]
    [(bigger-list? l) 
     (+ (bigger-list-first l)
        (aq-weight (bigger-list-rest l)))]))

(aq-weight empty) "should be" 0
(aq-weight (make-bigger-list 3 empty)) "should be" 3



;; ========================================
;;  Using the short names: cons, etc.
;; ========================================

; A list-of-num is either
;  - empty
;  - (cons num list-of-num)

; Aq-weight : list-of-num -> num
(define (Aq-weight l)
  (cond
    [(empty? l) 0]
    [(cons? l) (+ (first l) (Aq-weight (rest l)))]))

(Aq-weight empty) "should be" 0
(Aq-weight (cons 1 (cons 2 empty)))
"should be" 3