Chapter 2, Building Abstractions with Data
Section - 2.2 - Hierarchical Data and the Closure Property
Exercise 2.30
- Without using
map:
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#lang sicp
(define (square-tree tree)
(cond ((null? tree) nil)
((not (pair? tree)) (* tree tree))
(else
(cons
(square-tree (car tree))
(square-tree (cdr tree)))
)
)
)
Output:
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16
> (display
(square-tree
(list
1
(list
2
(list 3 4)
5
)
(list 6 7)
)
)
)
(1 (4 (9 16) 25) (36 49))
- With using
map:
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3
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5
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13
#lang sicp
(define (square-tree tree)
(map
(lambda (x)
(if (not (pair? x))
(* x x)
(square-tree x)
)
)
tree
)
)