; ======================================================================
;
;          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 07/14/05
;                                             modified:
; (保持内容完整不变前提下，可以任意转载)
; ======================================================================


;; SICP No.2.18

(define (reverse items)
  (define (reverse-iter i k)
    (if (null? i) k (reverse-iter (cdr i) (cons (car i) k))))
  (reverse-iter items ()))

;; Test-it:
;; Welcome to MzScheme version 209, Copyright (c) 2004 PLT Scheme, Inc.
;; > (reverse ())
;; ()
;; > (reverse (list 1))
;; (1)
;; > (reverse (list 1 4 9 16 25))
;; (25 16 9 4 1)