(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)))
(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 (count-change amount) (cc amount 5))
(count-change 100)
Java实现:/** * Created by Ramble on 2017/11/22. */public class ExchangeMoney { public static int first_denomination(int kinds_of_coin) { switch (kinds_of_coin) { case 1: { return 1; } case 2: { return 5; } case 3: { return 10; } case 4: { return 25; } case 5: { return 50; } default: return 0; } } public static int cc(int amount, int kinds_of_coin) { if (amount==0) { return 1; } else if (amount<0||kinds_of_coin==0) { return 0; } else { return cc(amount, kinds_of_coin-1) + cc(amount - first_denomination(kinds_of_coin), kinds_of_coin); } } public static int count_change(int amount) { return cc(amount, 5); } public static void main(String[] args) { long startTime = System.currentTimeMillis(); System.out.println(count_change(1000)); long endTime = System.currentTimeMillis(); System.out.println("程序运行时间："+(endTime-startTime)+"ms"); }}
转载于:https://www.cnblogs.com/R4mble/p/7881868.html
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