Petar Kapriš
1b2b2dfec1
To be noted: the last two exercises, 2.15 and 2.16 were left unfinished, and will be left for another time.
29 lines
505 B
Scheme
29 lines
505 B
Scheme
#lang sicp
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(define (cons a b)
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(* (expt 2 a)
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(expt 3 b)))
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(define (car pair)
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(if (= (remainder pair 3) 0)
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(car (/ pair 3))
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(log2 pair)))
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(define (cdr pair)
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(if (= (remainder pair 2) 0)
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(cdr (/ pair 2))
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(log3 pair)))
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(define (log2 num)
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(define (aux num acc)
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(if (<= num 1)
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acc
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(aux (/ num 2) (+ acc 1))))
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(aux num 0))
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(define (log3 num)
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(define (aux num acc)
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(if (<= num 1)
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acc
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(aux (/ num 3) (+ acc 1))))
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(aux num 0))
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