61 lines
1.6 KiB
Markdown
61 lines
1.6 KiB
Markdown
---
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id: 59713bd26bdeb8a594fb9413
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title: 计算硬币
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challengeType: 5
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videoUrl: ''
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dashedName: count-the-coins
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---
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# --description--
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<p> <a href='https://en.wikipedia.org/wiki/United_States' title='链接：https：//en.wikipedia.org/wiki/United_States'>美国</a>货币有四种常见硬币： </p>季度（25美分）硬币（10美分）镍（5美分）和便士（1美分） <p>有六种方法可以换15美分： </p>一角钱和一角钱一角钱和5便士3镍2镍和5便士一镍和10便士15便士任务： <p>实现一个功能，以确定使用这些普通硬币改变一美元的方式有多少？ （1美元= 100美分）。 </p>参考： <a href='http://mitpress.mit.edu/sicp/full-text/book/book-Z-H-11.html#%_sec_Temp_52' title='链接：http：//mitpress.mit.edu/sicp/full-text/book/book-Z-H-11.html#%_sec_Temp_52'>麻省理工学院出版社的算法</a> 。
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# --hints--
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`countCoins`是一个函数。
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```js
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assert(typeof countCoins === 'function');
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```
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`countCoints()`应该返回242。
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```js
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assert.equal(countCoins(), 242);
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```
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# --seed--
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## --seed-contents--
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```js
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function countCoins() {
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return true;
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}
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```
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# --solutions--
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```js
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function countCoins() {
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let t = 100;
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const operands = [1, 5, 10, 25];
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const targetsLength = t + 1;
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const operandsLength = operands.length;
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t = [1];
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for (let a = 0; a < operandsLength; a++) {
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for (let b = 1; b < targetsLength; b++) {
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// initialise undefined target
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t[b] = t[b] ? t[b] : 0;
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// accumulate target + operand ways
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t[b] += (b < operands[a]) ? 0 : t[b - operands[a]];
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}
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}
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return t[targetsLength - 1];
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}
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```
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