freeCodeCamp/curriculum/challenges/chinese/02-javascript-algorithms-and-data-structures/basic-algorithm-scripting/repeat-a-string-repeat-a-string.md

---
id: afcc8d540bea9ea2669306b6
title: Repeat a String Repeat a String
challengeType: 5
forumTopicId: 16041
dashedName: repeat-a-string-repeat-a-string
---

# --description--

Repeat a given string `str` (first argument) for `num` times (second argument). Return an empty string if `num` is not a positive number. For the purpose of this challenge, do *not* use the built-in `.repeat()` method.

# --hints--

`repeatStringNumTimes("*", 3)` should return `"***"`.

```js
assert(repeatStringNumTimes('*', 3) === '***');
```

`repeatStringNumTimes("abc", 3)` should return `"abcabcabc"`.

```js
assert(repeatStringNumTimes('abc', 3) === 'abcabcabc');
```

`repeatStringNumTimes("abc", 4)` should return `"abcabcabcabc"`.

```js
assert(repeatStringNumTimes('abc', 4) === 'abcabcabcabc');
```

`repeatStringNumTimes("abc", 1)` should return `"abc"`.

```js
assert(repeatStringNumTimes('abc', 1) === 'abc');
```

`repeatStringNumTimes("*", 8)` should return `"********"`.

```js
assert(repeatStringNumTimes('*', 8) === '********');
```

`repeatStringNumTimes("abc", -2)` should return `""`.

```js
assert(repeatStringNumTimes('abc', -2) === '');
```

The built-in `repeat()` method should not be used.

```js
assert(!/\.repeat/g.test(code));
```

`repeatStringNumTimes("abc", 0)` should return `""`.

```js
assert(repeatStringNumTimes('abc', 0) === '');
```

# --seed--

## --seed-contents--

```js
function repeatStringNumTimes(str, num) {
  return str;
}

repeatStringNumTimes("abc", 3);
```

# --solutions--

```js
function repeatStringNumTimes(str, num) {
  if (num < 1) return '';
  return num === 1 ? str : str + repeatStringNumTimes(str, num-1);
}

repeatStringNumTimes("abc", 3);
```