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---
id: 56592a60ddddeae28f7aa8e1
title: Access Multi-Dimensional Arrays With Indexes
challengeType: 1
videoUrl: 'https://scrimba.com/c/ckND4Cq'
forumTopicId: 16159
dashedName: access-multi-dimensional-arrays-with-indexes
---
# --description--
One way to think of a <dfn>multi-dimensional</dfn> array, is as an *array of arrays*. When you use brackets to access your array, the first set of brackets refers to the entries in the outer-most (the first level) array, and each additional pair of brackets refers to the next level of entries inside.
**Example**
```js
var arr = [
[1,2,3],
[4,5,6],
[7,8,9],
[[10,11,12], 13, 14]
];
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
arr[3];
arr[3][0];
arr[3][0][1];
```
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
`arr[3]` is `[[10, 11, 12], 13, 14]`, `arr[3][0]` is `[10, 11, 12]`, and `arr[3][0][1]` is `11`.
**Note:** There shouldn't be any spaces between the array name and the square brackets, like `array [0][0]` and even this `array [0] [0]` is not allowed. Although JavaScript is able to process this correctly, this may confuse other programmers reading your code.
# --instructions--
Using bracket notation select an element from `myArray` such that `myData` is equal to `8`.
# --hints--
`myData` should be equal to `8`.
```js
assert(myData === 8);
```
You should be using bracket notation to read the correct value from `myArray`.
```js
assert(/myData=myArray\[2\]\[1\]/.test(__helpers.removeWhiteSpace(code)));
```
# --seed--
## --after-user-code--
```js
if(typeof myArray !== "undefined"){(function(){return "myData: " + myData + " myArray: " + JSON.stringify(myArray);})();}
```
## --seed-contents--
```js
var myArray = [[1,2,3], [4,5,6], [7,8,9], [[10,11,12], 13, 14]];
var myData = myArray[0][0];
```
# --solutions--
```js
var myArray = [[1,2,3],[4,5,6], [7,8,9], [[10,11,12], 13, 14]];
var myData = myArray[2][1];
```