freeCodeCamp/curriculum/challenges/english/02-javascript-algorithms-an.../basic-javascript/manipulate-arrays-with-shif...

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---
id: 56bbb991ad1ed5201cd392cd
title: Manipulate Arrays With shift()
challengeType: 1
videoUrl: 'https://scrimba.com/c/cRbVETW'
---
## Description
<section id='description'>
<code>pop()</code> always removes the last element of an array. What if you want to remove the first?
That's where <code>.shift()</code> comes in. It works just like <code>.pop()</code>, except it removes the first element instead of the last.
</section>
## Instructions
<section id='instructions'>
Use the <code>.shift()</code> function to remove the first item from <code>myArray</code>, assigning the "shifted off" value to <code>removedFromMyArray</code>.
</section>
## Tests
<section id='tests'>
```yml
tests:
- text: <code>myArray</code> should now equal <code>[["dog", 3]]</code>.
testString: assert((function(d){if(d[0][0] == 'dog' && d[0][1] === 3 && d[1] == undefined){return true;}else{return false;}})(myArray));
- text: <code>removedFromMyArray</code> should contain <code>["John", 23]</code>.
testString: assert((function(d){if(d[0] == 'John' && d[1] === 23 && typeof removedFromMyArray === 'object'){return true;}else{return false;}})(removedFromMyArray));
```
</section>
## Challenge Seed
<section id='challengeSeed'>
<div id='js-seed'>
```js
// Example
var ourArray = ["Stimpson", "J", ["cat"]];
var removedFromOurArray = ourArray.shift();
// removedFromOurArray now equals "Stimpson" and ourArray now equals ["J", ["cat"]].
// Setup
var myArray = [["John", 23], ["dog", 3]];
// Only change code below this line.
var removedFromMyArray;
```
</div>
### After Test
<div id='js-teardown'>
```js
(function(y, z){return 'myArray = ' + JSON.stringify(y) + ' & removedFromMyArray = ' + JSON.stringify(z);})(myArray, removedFromMyArray);
```
</div>
</section>
## Solution
<section id='solution'>
```js
var myArray = [["John", 23], ["dog", 3]];
// Only change code below this line.
var removedFromMyArray = myArray.shift();
```
</section>