A total function.

Goal

Print 25 from a recursive sum.

(define (total xs)
  (if (null? xs)
      0
      (+ (car xs) (total (cdr xs)))))
(print (total '(12 8 5)))

(define (len xs)
  (if (null? xs)
      0
      (+ 1 (len (cdr xs)))))
(print (len '(Nairobi Mombasa Kisumu)))

(define (fact n)
  (if (<= n 1)
      1
      (* n (fact (- n 1)))))
(print (fact 5))

(define (total xs)
  (if (null? xs)
      0
      (+ (car xs) (total (cdr xs)))))
(print (total '(4 3)))