2018-10-10 18:03:03 -04:00
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---
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id: afcc8d540bea9ea2669306b6
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2020-12-16 00:37:30 -07:00
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title: 重复一个字符串重复字符串
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2018-10-10 18:03:03 -04:00
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challengeType: 5
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videoUrl: ''
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---
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2020-12-16 00:37:30 -07:00
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# --description--
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为`num` times(第二个参数)重复给定的字符串`str` (第一个参数)。如果`num`不是正数,则返回空字符串。如果卡住,请记得使用[Read-Search-Ask](https://forum.freecodecamp.org/t/how-to-get-help-when-you-are-stuck-coding/19514) 。编写自己的代码。
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# --hints--
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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`repeatStringNumTimes("*", 3)`应该返回`"***"` 。
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```js
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assert(repeatStringNumTimes('*', 3) === '***');
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2018-10-10 18:03:03 -04:00
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```
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2020-12-16 00:37:30 -07:00
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`repeatStringNumTimes("abc", 3)`应该返回`"abcabcabc"` 。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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```js
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assert(repeatStringNumTimes('abc', 3) === 'abcabcabc');
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```
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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`repeatStringNumTimes("abc", 4)`应返回`"abcabcabcabc"` 。
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2018-10-10 18:03:03 -04:00
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```js
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2020-12-16 00:37:30 -07:00
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assert(repeatStringNumTimes('abc', 4) === 'abcabcabcabc');
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```
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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`repeatStringNumTimes("abc", 1)`应该返回`"abc"` 。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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```js
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assert(repeatStringNumTimes('abc', 1) === 'abc');
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2018-10-10 18:03:03 -04:00
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```
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2020-12-16 00:37:30 -07:00
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`repeatStringNumTimes("*", 8)`应该返回`"********"` 。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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```js
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assert(repeatStringNumTimes('*', 8) === '********');
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```
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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`repeatStringNumTimes("abc", -2)`应返回`""` 。
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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```js
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assert(repeatStringNumTimes('abc', -2) === '');
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```
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2018-10-10 18:03:03 -04:00
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2020-12-16 00:37:30 -07:00
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不应使用内置的`repeat()`方法
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2018-10-10 18:03:03 -04:00
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```js
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2020-12-16 00:37:30 -07:00
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assert(!/\.repeat/g.test(code));
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2018-10-10 18:03:03 -04:00
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```
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2020-08-13 17:24:35 +02:00
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2020-12-16 00:37:30 -07:00
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# --solutions--
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