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

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---
id: 56bbb991ad1ed5201cd392cc
title: Manipulate Arrays With pop()
challengeType: 1
---
## Description
<section id='description'>
Another way to change the data in an array is with the <code>.pop()</code> function.
<code>.pop()</code> is used to "pop" a value off of the end of an array. We can store this "popped off" value by assigning it to a variable. In other words, <code>.pop()</code> removes the last element from an array and returns that element.
Any type of entry can be "popped" off of an array - numbers, strings, even nested arrays.
<blockquote><code>var threeArr = [1, 4, 6];<br> var oneDown = threeArr.pop();<br> console.log(oneDown); // Returns 6<br> console.log(threeArr); // Returns [1, 4]</code></blockquote>
</section>
## Instructions
<section id='instructions'>
Use the <code>.pop()</code> function to remove the last item from <code>myArray</code>, assigning the "popped off" value to <code>removedFromMyArray</code>.
</section>
## Tests
<section id='tests'>
```yml
tests:
- text: <code>myArray</code> should only contain <code>[["John", 23]]</code>.
testString: assert((function(d){if(d[0][0] == 'John' && d[0][1] === 23 && d[1] == undefined){return true;}else{return false;}})(myArray), '<code>myArray</code> should only contain <code>[["John", 23]]</code>.');
- text: Use <code>pop()</code> on <code>myArray</code>
testString: assert(/removedFromMyArray\s*=\s*myArray\s*.\s*pop\s*(\s*)/.test(code), 'Use <code>pop()</code> on <code>myArray</code>');
- text: <code>removedFromMyArray</code> should only contain <code>["cat", 2]</code>.
testString: assert((function(d){if(d[0] == 'cat' && d[1] === 2 && d[2] == undefined){return true;}else{return false;}})(removedFromMyArray), '<code>removedFromMyArray</code> should only contain <code>["cat", 2]</code>.');
```
</section>
## Challenge Seed
<section id='challengeSeed'>
<div id='js-seed'>
```js
// Example
var ourArray = [1,2,3];
var removedFromOurArray = ourArray.pop();
// removedFromOurArray now equals 3, and ourArray now equals [1,2]
// Setup
var myArray = [["John", 23], ["cat", 2]];
// 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], ["cat", 2]];
var removedFromMyArray = myArray.pop();
```
</section>