69 lines
2.7 KiB
Markdown
69 lines
2.7 KiB
Markdown
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---
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id: afcc8d540bea9ea2669306b6
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title: Repeat a String Repeat a String
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isRequired: true
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challengeType: 5
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videoUrl: ''
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localeTitle: 重复一个字符串重复字符串
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---
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## Description
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<section id="description">为<code>num</code> times（第二个参数）重复给定的字符串<code>str</code> （第一个参数）。如果<code>num</code>不是正数，则返回空字符串。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> 。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>repeatStringNumTimes("*", 3)</code>应该返回<code>"***"</code> 。'
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testString: 'assert(repeatStringNumTimes("*", 3) === "***", "<code>repeatStringNumTimes("*", 3)</code> should return <code>"***"</code>.");'
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- text: '<code>repeatStringNumTimes("abc", 3)</code>应该返回<code>"abcabcabc"</code> 。'
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testString: 'assert(repeatStringNumTimes("abc", 3) === "abcabcabc", "<code>repeatStringNumTimes("abc", 3)</code> should return <code>"abcabcabc"</code>.");'
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- text: '<code>repeatStringNumTimes("abc", 4)</code>应返回<code>"abcabcabcabc"</code> 。'
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testString: 'assert(repeatStringNumTimes("abc", 4) === "abcabcabcabc", "<code>repeatStringNumTimes("abc", 4)</code> should return <code>"abcabcabcabc"</code>.");'
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- text: '<code>repeatStringNumTimes("abc", 1)</code>应该返回<code>"abc"</code> 。'
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testString: 'assert(repeatStringNumTimes("abc", 1) === "abc", "<code>repeatStringNumTimes("abc", 1)</code> should return <code>"abc"</code>.");'
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- text: '<code>repeatStringNumTimes("*", 8)</code>应该返回<code>"********"</code> 。'
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testString: 'assert(repeatStringNumTimes("*", 8) === "********", "<code>repeatStringNumTimes("*", 8)</code> should return <code>"********"</code>.");'
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- text: '<code>repeatStringNumTimes("abc", -2)</code>应返回<code>""</code> 。'
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testString: 'assert(repeatStringNumTimes("abc", -2) === "", "<code>repeatStringNumTimes("abc", -2)</code> should return <code>""</code>.");'
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- text: 不应使用内置的<code>repeat()</code>方法
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testString: 'assert(!/\.repeat/g.test(code), "The built-in <code>repeat()</code>-method should not be used");'
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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 repeatStringNumTimes(str, num) {
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// repeat after me
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return str;
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}
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repeatStringNumTimes("abc", 3);
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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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