; ======================================================================
;
; 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 07/27/05
; modified:
; (保持内容完整不变前提下，可以任意转载)
; ======================================================================
;; SICP No.2.21
(require (lib "math.ss"))
(define (square-list-basic items)
(if (null? items)
()
(cons (sqr (car items)) (square-list-basic (cdr items)))))
(define (square-list-with-map items)
(map sqr items))
;; Test-it:
;; Welcome to MzScheme version 209, Copyright (c) 2004 PLT Scheme, Inc.
;; > (define test-data (list 1 2 3 4))
;; > (square-list-basic test-data)
;; (1 4 9 16)
;; > (square-list-with-map test-data)
;; (1 4 9 16)
