sicp习题试解 (2.27)

; ======================================================================

;

; 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 07/28/05

; modified:

; (保持内容完整不变前提下，可以任意转载)

; ======================================================================

;; SICP No.2.27

(define (deep-reverse x)

(if (pair? x)

(append (deep-reverse (cdr x)) (list (deep-reverse (car x))))

x))

;; Test-it:

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

;; > (define x (list (list 1 2) (list 3 4)))

;; > x

;; ((1 2) (3 4))

;; > (deep-reverse x)

;; ((4 3) (2 1))