[SICP]分硬币问题

laihj    负暄琐话     SICP

(define (count-change amount)
(cc amount 5))

(define (cc amount kinds-of-coin)
(cond ((= amount 0) 1)
((or (< amount 0) (= kinds-of-coin 0)) 0 )
(else (+ (cc amount (- kinds-of-coin 1))
(cc (- amount (first-denomination kinds-of-coin)) kinds-of-coin))
)
)
)

(define (first-denomination kinds-of-coin)
(cond ((= kinds-of-coin 1) 1)
((= kinds-of-coin 2) 5)
((= kinds-of-coin 3) 10)
((= kinds-of-coin 4) 25)
((= kinds-of-coin 5) 50)
)
)

(count-change 100)