(load "2.33.txt") ; for accumulate

(define (count-leaves t)
  (accumulate +
              0
              (map (lambda (n)
                     (if (list? n) (count-leaves n) 1))
                   t)))

; 1 ]=> (count-leaves '())
; 
; ;Value: 0
; 
; 1 ]=> (count-leaves '(1 2 3))
; 
; ;Value: 3
; 
; 1 ]=> (count-leaves '(1 (2 3) (((4) 5) 6 7) 8))
; 
; ;Value: 8