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

79 lines
2.9 KiB
Markdown
Raw Normal View History

2018-10-08 17:34:43 +00:00
---
id: afcc8d540bea9ea2669306b6
title: Repeat a String Repeat a String
localeTitle: Repetir una cadena Repetir una cadena
isRequired: true
challengeType: 5
---
## Description
<section id='description'>
Repetir una determinada cadena <code>str</code> (primer argumento) para <code>num</code> veces (segundo argumento). Devuelve una cadena vacía si <code>num</code> no es un número positivo.
Recuerda usar <a href="http://forum.freecodecamp.org/t/how-to-get-help-when-you-are-stuck/19514" target="_blank">Read-Search-Ask</a> si te atascas. Escribe tu propio código.
</section>
## Instructions
<section id='instructions'>
</section>
## Tests
<section id='tests'>
```yml
tests:
- text: &#39; <code>repeatStringNumTimes(&quot;*&quot;, 3)</code> debe devolver <code>&quot;***&quot;</code> .&#39;
testString: 'assert(repeatStringNumTimes("*", 3) === "***", "<code>repeatStringNumTimes("*", 3)</code> should return <code>"***"</code>.");'
- text: &#39; <code>repeatStringNumTimes(&quot;abc&quot;, 3)</code> debe devolver <code>&quot;abcabcabc&quot;</code> .&#39;
testString: 'assert(repeatStringNumTimes("abc", 3) === "abcabcabc", "<code>repeatStringNumTimes("abc", 3)</code> should return <code>"abcabcabc"</code>.");'
- text: &#39; <code>repeatStringNumTimes(&quot;abc&quot;, 4)</code> debe devolver <code>&quot;abcabcabcabc&quot;</code> .&#39;
testString: 'assert(repeatStringNumTimes("abc", 4) === "abcabcabcabc", "<code>repeatStringNumTimes("abc", 4)</code> should return <code>"abcabcabcabc"</code>.");'
- text: &#39; <code>repeatStringNumTimes(&quot;abc&quot;, 1)</code> debe devolver <code>&quot;abc&quot;</code> .&#39;
testString: 'assert(repeatStringNumTimes("abc", 1) === "abc", "<code>repeatStringNumTimes("abc", 1)</code> should return <code>"abc"</code>.");'
- text: &#39; <code>repeatStringNumTimes(&quot;*&quot;, 8)</code> debe devolver <code>&quot;********&quot;</code> .&#39;
testString: 'assert(repeatStringNumTimes("*", 8) === "********", "<code>repeatStringNumTimes("*", 8)</code> should return <code>"********"</code>.");'
- text: &#39; <code>repeatStringNumTimes(&quot;abc&quot;, -2)</code> debe devolver <code>&quot;&quot;</code> .&#39;
testString: 'assert(repeatStringNumTimes("abc", -2) === "", "<code>repeatStringNumTimes("abc", -2)</code> should return <code>""</code>.");'
- text: El método <code>repeat()</code> incorporado no debe utilizarse
testString: 'assert(!/\.repeat/g.test(code), "The built-in <code>repeat()</code>-method should not be used");'
```
</section>
## Challenge Seed
<section id='challengeSeed'>
<div id='js-seed'>
```js
function repeatStringNumTimes(str, num) {
// repeat after me
return str;
}
repeatStringNumTimes("abc", 3);
```
</div>
</section>
## Solution
<section id='solution'>
```js
function repeatStringNumTimes(str, num) {
if (num < 0) return ";
return num === 1 ? str : str + repeatStringNumTimes(str, num-1);
}
repeatStringNumTimes("abc", 3);
```
</section>