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

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---
id: 56bbb991ad1ed5201cd392cc
title: Manipulate Arrays With pop()
challengeType: 1
videoUrl: 'https://scrimba.com/c/cRbVZAB'
forumTopicId: 18236
dashedName: manipulate-arrays-with-pop
---
# --description--
Another way to change the data in an array is with the `.pop()` function.
chore(learn): audit javascript algorithms and data structures (#41092) * chore(learn): audit basic algorithm scripting * chore(learn): audit basic data structures * chore(learn): audit basic javascript * chore(learn): audit debugging * chore(learn): audit es6 * chore(learn): audit functional programming * chore(learn): audit intermidate algorithms * chore(learn): audit js projects * chore(learn): audit object oriented programming * chore(learn): audit regex * fix(learn): remove stray . * fix(learn): string to code * fix(learn): missed some * fix(learn): clarify strings Based on Randy's feedback, clarifies string instances where quotes were removed in favour of back ticks. * fix: apply suggestions - thanks Randy! :) Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> * fix: non-suggestion comments * chore(learn): remove comments from codes Removes the comments from the description and instruction code blocks to ensure that all relevant information is translatable. * fix: Apply suggestions from code review Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * fix: revert crowdin fix * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-algorithm-scripting/mutations.md Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> * fix: Apply suggestions from code review Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/es6/use-destructuring-assignment-to-assign-variables-from-arrays.md Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * fix: Apply suggestions from code review Co-authored-by: Oliver Eyton-Williams <ojeytonwilliams@gmail.com> Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * chore: change voice * fix: Christopher Nolan * fix: expressions would evaluate * fix: will -> would * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/object-oriented-programming/add-methods-after-inheritance.md Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> * fix: to work to push * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-javascript/iterate-with-javascript-for-loops.md Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/object-oriented-programming/add-methods-after-inheritance.md Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> Co-authored-by: Oliver Eyton-Williams <ojeytonwilliams@gmail.com>
2021-03-03 00:12:12 +00:00
`.pop()` 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, `.pop()` removes the last element from an array and returns that element.
chore(learn): audit javascript algorithms and data structures (#41092) * chore(learn): audit basic algorithm scripting * chore(learn): audit basic data structures * chore(learn): audit basic javascript * chore(learn): audit debugging * chore(learn): audit es6 * chore(learn): audit functional programming * chore(learn): audit intermidate algorithms * chore(learn): audit js projects * chore(learn): audit object oriented programming * chore(learn): audit regex * fix(learn): remove stray . * fix(learn): string to code * fix(learn): missed some * fix(learn): clarify strings Based on Randy's feedback, clarifies string instances where quotes were removed in favour of back ticks. * fix: apply suggestions - thanks Randy! :) Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> * fix: non-suggestion comments * chore(learn): remove comments from codes Removes the comments from the description and instruction code blocks to ensure that all relevant information is translatable. * fix: Apply suggestions from code review Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * fix: revert crowdin fix * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-algorithm-scripting/mutations.md Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> * fix: Apply suggestions from code review Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/es6/use-destructuring-assignment-to-assign-variables-from-arrays.md Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * fix: Apply suggestions from code review Co-authored-by: Oliver Eyton-Williams <ojeytonwilliams@gmail.com> Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * chore: change voice * fix: Christopher Nolan * fix: expressions would evaluate * fix: will -> would * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/object-oriented-programming/add-methods-after-inheritance.md Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> * fix: to work to push * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-javascript/iterate-with-javascript-for-loops.md Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/object-oriented-programming/add-methods-after-inheritance.md Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> Co-authored-by: Oliver Eyton-Williams <ojeytonwilliams@gmail.com>
2021-03-03 00:12:12 +00:00
Any type of entry can be popped off of an array - numbers, strings, even nested arrays.
```js
var threeArr = [1, 4, 6];
var oneDown = threeArr.pop();
chore(learn): audit javascript algorithms and data structures (#41092) * chore(learn): audit basic algorithm scripting * chore(learn): audit basic data structures * chore(learn): audit basic javascript * chore(learn): audit debugging * chore(learn): audit es6 * chore(learn): audit functional programming * chore(learn): audit intermidate algorithms * chore(learn): audit js projects * chore(learn): audit object oriented programming * chore(learn): audit regex * fix(learn): remove stray . * fix(learn): string to code * fix(learn): missed some * fix(learn): clarify strings Based on Randy's feedback, clarifies string instances where quotes were removed in favour of back ticks. * fix: apply suggestions - thanks Randy! :) Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> * fix: non-suggestion comments * chore(learn): remove comments from codes Removes the comments from the description and instruction code blocks to ensure that all relevant information is translatable. * fix: Apply suggestions from code review Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * fix: revert crowdin fix * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-algorithm-scripting/mutations.md Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> * fix: Apply suggestions from code review Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/es6/use-destructuring-assignment-to-assign-variables-from-arrays.md Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * fix: Apply suggestions from code review Co-authored-by: Oliver Eyton-Williams <ojeytonwilliams@gmail.com> Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * chore: change voice * fix: Christopher Nolan * fix: expressions would evaluate * fix: will -> would * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/object-oriented-programming/add-methods-after-inheritance.md Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> * fix: to work to push * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-javascript/iterate-with-javascript-for-loops.md Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/object-oriented-programming/add-methods-after-inheritance.md Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> Co-authored-by: Oliver Eyton-Williams <ojeytonwilliams@gmail.com>
2021-03-03 00:12:12 +00:00
console.log(oneDown);
console.log(threeArr);
```
chore(learn): audit javascript algorithms and data structures (#41092) * chore(learn): audit basic algorithm scripting * chore(learn): audit basic data structures * chore(learn): audit basic javascript * chore(learn): audit debugging * chore(learn): audit es6 * chore(learn): audit functional programming * chore(learn): audit intermidate algorithms * chore(learn): audit js projects * chore(learn): audit object oriented programming * chore(learn): audit regex * fix(learn): remove stray . * fix(learn): string to code * fix(learn): missed some * fix(learn): clarify strings Based on Randy's feedback, clarifies string instances where quotes were removed in favour of back ticks. * fix: apply suggestions - thanks Randy! :) Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> * fix: non-suggestion comments * chore(learn): remove comments from codes Removes the comments from the description and instruction code blocks to ensure that all relevant information is translatable. * fix: Apply suggestions from code review Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * fix: revert crowdin fix * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-algorithm-scripting/mutations.md Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> * fix: Apply suggestions from code review Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/es6/use-destructuring-assignment-to-assign-variables-from-arrays.md Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * fix: Apply suggestions from code review Co-authored-by: Oliver Eyton-Williams <ojeytonwilliams@gmail.com> Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * chore: change voice * fix: Christopher Nolan * fix: expressions would evaluate * fix: will -> would * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/object-oriented-programming/add-methods-after-inheritance.md Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> * fix: to work to push * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-javascript/iterate-with-javascript-for-loops.md Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/object-oriented-programming/add-methods-after-inheritance.md Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> Co-authored-by: Oliver Eyton-Williams <ojeytonwilliams@gmail.com>
2021-03-03 00:12:12 +00:00
The first `console.log` will display the value `6`, and the second will display the value `[1, 4]`.
# --instructions--
chore(learn): audit javascript algorithms and data structures (#41092) * chore(learn): audit basic algorithm scripting * chore(learn): audit basic data structures * chore(learn): audit basic javascript * chore(learn): audit debugging * chore(learn): audit es6 * chore(learn): audit functional programming * chore(learn): audit intermidate algorithms * chore(learn): audit js projects * chore(learn): audit object oriented programming * chore(learn): audit regex * fix(learn): remove stray . * fix(learn): string to code * fix(learn): missed some * fix(learn): clarify strings Based on Randy's feedback, clarifies string instances where quotes were removed in favour of back ticks. * fix: apply suggestions - thanks Randy! :) Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> * fix: non-suggestion comments * chore(learn): remove comments from codes Removes the comments from the description and instruction code blocks to ensure that all relevant information is translatable. * fix: Apply suggestions from code review Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * fix: revert crowdin fix * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-algorithm-scripting/mutations.md Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> * fix: Apply suggestions from code review Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/es6/use-destructuring-assignment-to-assign-variables-from-arrays.md Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * fix: Apply suggestions from code review Co-authored-by: Oliver Eyton-Williams <ojeytonwilliams@gmail.com> Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * chore: change voice * fix: Christopher Nolan * fix: expressions would evaluate * fix: will -> would * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/object-oriented-programming/add-methods-after-inheritance.md Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> * fix: to work to push * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/basic-javascript/iterate-with-javascript-for-loops.md Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> * Update curriculum/challenges/english/02-javascript-algorithms-and-data-structures/object-oriented-programming/add-methods-after-inheritance.md Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> Co-authored-by: Randell Dawson <5313213+RandellDawson@users.noreply.github.com> Co-authored-by: Shaun Hamilton <51722130+ShaunSHamilton@users.noreply.github.com> Co-authored-by: Oliver Eyton-Williams <ojeytonwilliams@gmail.com>
2021-03-03 00:12:12 +00:00
Use the `.pop()` function to remove the last item from `myArray`, assigning the popped off value to `removedFromMyArray`.
# --hints--
`myArray` should only contain `[["John", 23]]`.
```js
assert(
(function (d) {
if (d[0][0] == 'John' && d[0][1] === 23 && d[1] == undefined) {
return true;
} else {
return false;
}
})(myArray)
);
```
You should use `pop()` on `myArray`.
```js
assert(/removedFromMyArray\s*=\s*myArray\s*.\s*pop\s*(\s*)/.test(code));
```
`removedFromMyArray` should only contain `["cat", 2]`.
```js
assert(
(function (d) {
if (d[0] == 'cat' && d[1] === 2 && d[2] == undefined) {
return true;
} else {
return false;
}
})(removedFromMyArray)
);
```
# --seed--
## --after-user-code--
```js
(function(y, z){return 'myArray = ' + JSON.stringify(y) + ' & removedFromMyArray = ' + JSON.stringify(z);})(myArray, removedFromMyArray);
```
## --seed-contents--
```js
// Setup
var myArray = [["John", 23], ["cat", 2]];
// Only change code below this line
var removedFromMyArray;
```
# --solutions--
```js
var myArray = [["John", 23], ["cat", 2]];
var removedFromMyArray = myArray.pop();
```