sicp习题试解 (2.35)

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;

; Structure and Interpretation of Computer Programs

; (trial answer to excercises)

;

; 计算机程序的构造和解释(习题试解)

;

; created: code17 08/19/05

; modified:

; (保持内容完整不变前提下，可以任意转载)

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;; SICP No.2.35

(define (count-leaves t)

(accumulate + 0 (map (lambda (x) (if (pair? x) (count-leaves x) 1)) t)))

;; Test-it:

;; Welcome to MzScheme version 209, Copyright (c) 2004 PLT Scheme, Inc.

;; > (count-leaves (list 1 2 (list 3 4 (list 5)) 6 (list 7 8)))

;; 8