59 lines
1.6 KiB
Markdown
59 lines
1.6 KiB
Markdown
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---
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id: a6e40f1041b06c996f7b2406
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title: Finders Keepers
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isRequired: true
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challengeType: 5
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videoUrl: ''
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localeTitle: Finders Keepers
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---
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## Description
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<section id="description">创建一个查看数组（第一个参数）的函数，并返回数组中传递真值测试的第一个元素（第二个参数）。如果没有元素通过测试，则返回undefined。如果卡住，请记得使用<a href="http://forum.freecodecamp.org/t/how-to-get-help-when-you-are-stuck/19514" target="_blank">Read-Search-Ask</a> 。尝试配对程序。编写自己的代码。 </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>findElement([1, 3, 5, 8, 9, 10], function(num) { return num % 2 === 0; })</code>应该返回8。'
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testString: 'assert.strictEqual(findElement([1, 3, 5, 8, 9, 10], function(num) { return num % 2 === 0; }), 8, "<code>findElement([1, 3, 5, 8, 9, 10], function(num) { return num % 2 === 0; })</code> should return 8.");'
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- text: '<code>findElement([1, 3, 5, 9], function(num) { return num % 2 === 0; })</code>应返回undefined。'
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testString: 'assert.strictEqual(findElement([1, 3, 5, 9], function(num) { return num % 2 === 0; }), undefined, "<code>findElement([1, 3, 5, 9], function(num) { return num % 2 === 0; })</code> should return undefined.");'
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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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function findElement(arr, func) {
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let num = 0;
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return num;
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}
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findElement([1, 2, 3, 4], num => num % 2 === 0);
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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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