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freeCodeCamp/curriculum/challenges/english/02-javascript-algorithms-and-data-structures/regular-expressions/remove-whitespace-from-start-and-end.english.md

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---
id: 587d7dbb367417b2b2512bac
title: Remove Whitespace from Start and End
challengeType: 1
forumTopicId: 301362
---
## Description
<section id='description'>
Sometimes whitespace characters around strings are not wanted but are there. Typical processing of strings is to remove the whitespace at the start and end of it.
</section>
## Instructions
<section id='instructions'>
Write a regex and use the appropriate string methods to remove whitespace at the beginning and end of strings.
<strong>Note:</strong> The <code>String.prototype.trim()</code> method would work here, but you'll need to complete this challenge using regular expressions.
</section>
## Tests
<section id='tests'>
```yml
tests:
- text: <code>result</code> should equal to <code>"Hello, World!"</code>
testString: assert(result == "Hello, World!");
- text: Your solution should not use the <code>String.prototype.trim()</code> method.
testString: assert(!code.match(/\.trim\([\s\S]*?\)/));
- text: The <code>result</code> variable should not be set equal to a string.
testString: assert(!code.match(/result\s*=\s*".*?"/));
```
</section>
## Challenge Seed
<section id='challengeSeed'>
<div id='js-seed'>
```js
let hello = " Hello, World! ";
let wsRegex = /change/; // Change this line
let result = hello; // Change this line
```
</div>
</section>
## Solution
<section id='solution'>
```js
let hello = " Hello, World! ";
let wsRegex = /^(\s+)(.+[^\s])(\s+)$/;
let result = hello.replace(wsRegex, '$2');
```
</section>