67 lines
2.1 KiB
Markdown
67 lines
2.1 KiB
Markdown
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---
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title: Hailstone sequence
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id: 595608ff8bcd7a50bd490181
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challengeType: 5
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videoUrl: ''
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localeTitle: 冰雹序列
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---
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## Description
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<section id="description"><p> Hailstone数字序列可以从起始正整数n生成: </p>如果n为1,则序列结束。如果n是偶数,那么序列的下一个n <code>= n/2</code>如果n是奇数,那么序列的下一个n <code>= (3 * n) + 1</code> <p> (未经证实的) <a href="https://en.wikipedia.org/wiki/Collatz conjecture" title="wp:Collatz猜想">Collatz猜想</a>是任何起始编号的冰雹序列总是终止。 </p><p>冰雹序列也称为冰雹数(因为这些值通常受到多个下降和上升,如云中的冰雹),或者作为Collatz序列。 </p>任务:创建例程以生成数字的hailstone序列。使用例程表明,对于27号的冰雹序列具有开始与112个元件<code>27, 82, 41, 124</code> ,结束时用<code>8, 4, 2, 1</code>与显示具有最长冰雹序列的数目少于100,000一起序列的长度。 (但不要显示实际的序列!)参见: <a href="http://xkcd.com/710" title="链接:http://xkcd.com/710">xkcd</a> (幽默)。 </section>
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## Instructions
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<section id="instructions">
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</section>
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## Tests
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<section id='tests'>
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```yml
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tests:
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- text: <code>hailstoneSequence</code>是一个函数。
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testString: 'assert(typeof hailstoneSequence === "function", "<code>hailstoneSequence</code> is a function.");'
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- text: '<code>[[27,82,41,124,8,4,2,1], [351, 77031]]</code> <code>hailstoneSequence()</code>应返回<code>[[27,82,41,124,8,4,2,1], [351, 77031]]</code>'
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testString: 'assert.deepEqual(hailstoneSequence(), res, "<code>hailstoneSequence()</code> should return <code>[[27,82,41,124,8,4,2,1], [351, 77031]]</code>");'
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```
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</section>
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## Challenge Seed
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<section id='challengeSeed'>
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<div id='js-seed'>
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```js
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// noprotect
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function hailstoneSequence () {
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const res = [];
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// Good luck!
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return res;
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}
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```
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</div>
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### After Test
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<div id='js-teardown'>
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```js
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console.info('after the test');
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```
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</div>
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</section>
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## Solution
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<section id='solution'>
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```js
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// solution required
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```
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</section>
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