Created
September 20, 2011 15:48
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count-change from SICP Chapter 1
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(define (count-change amount) | |
(cc amount 5)) | |
(define (cc amount kinds-of-coins) | |
(cond ((= amount 0) 1) | |
((or (< amount 0) (= kinds-of-coins 0)) 0) | |
(else (+ (cc amount | |
(- kinds-of-coins 1)) | |
(cc (- amount | |
(first-denomination kinds-of-coins)) | |
kinds-of-coins))))) | |
(define (first-denomination kinds-of-coins) | |
(cond ((= kinds-of-coins 1) 1) | |
((= kinds-of-coins 2) 5) | |
((= kinds-of-coins 3) 10) | |
((= kinds-of-coins 4) 25) | |
((= kinds-of-coins 5) 50))) |
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