freeCodeCamp/curriculum/challenges/chinese/02-javascript-algorithms-an.../basic-algorithm-scripting/repeat-a-string-repeat-a-st...

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---
id: afcc8d540bea9ea2669306b6
title: 重复一个字符串重复字符串
challengeType: 5
videoUrl: ''
---
# --description--
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。
# --hints--
`repeatStringNumTimes("*", 3)`应该返回`"***"` 。
```js
assert(repeatStringNumTimes('*', 3) === '***');
```
`repeatStringNumTimes("abc", 3)`应该返回`"abcabcabc"` 。
```js
assert(repeatStringNumTimes('abc', 3) === 'abcabcabc');
```
`repeatStringNumTimes("abc", 4)`应返回`"abcabcabcabc"` 。
```js
assert(repeatStringNumTimes('abc', 4) === 'abcabcabcabc');
```
`repeatStringNumTimes("abc", 1)`应该返回`"abc"` 。
```js
assert(repeatStringNumTimes('abc', 1) === 'abc');
```
`repeatStringNumTimes("*", 8)`应该返回`"********"` 。
```js
assert(repeatStringNumTimes('*', 8) === '********');
```
`repeatStringNumTimes("abc", -2)`应返回`""` 。
```js
assert(repeatStringNumTimes('abc', -2) === '');
```
不应使用内置的`repeat()`方法
```js
assert(!/\.repeat/g.test(code));
```
# --solutions--