72 lines
1.8 KiB
Markdown
72 lines
1.8 KiB
Markdown
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---
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id: 56592a60ddddeae28f7aa8e1
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title: Access Multi-Dimensional Arrays With Indexes
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/ckND4Cq'
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forumTopicId: 16159
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dashedName: access-multi-dimensional-arrays-with-indexes
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---
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# --description--
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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.
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**Example**
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```js
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var arr = [
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[1,2,3],
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[4,5,6],
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[7,8,9],
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[[10,11,12], 13, 14]
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];
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arr[3];
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arr[3][0];
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arr[3][0][1];
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```
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`arr[3]` is `[[10, 11, 12], 13, 14]`, `arr[3][0]` is `[10, 11, 12]`, and `arr[3][0][1]` is `11`.
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**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.
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# --instructions--
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Using bracket notation select an element from `myArray` such that `myData` is equal to `8`.
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# --hints--
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`myData` should be equal to `8`.
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```js
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assert(myData === 8);
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```
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You should be using bracket notation to read the correct value from `myArray`.
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```js
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assert(/myData=myArray\[2\]\[1\]/.test(__helpers.removeWhiteSpace(code)));
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```
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# --seed--
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## --after-user-code--
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```js
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if(typeof myArray !== "undefined"){(function(){return "myData: " + myData + " myArray: " + JSON.stringify(myArray);})();}
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```
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## --seed-contents--
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```js
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var myArray = [[1,2,3], [4,5,6], [7,8,9], [[10,11,12], 13, 14]];
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var myData = myArray[0][0];
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```
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# --solutions--
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```js
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var myArray = [[1,2,3],[4,5,6], [7,8,9], [[10,11,12], 13, 14]];
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var myData = myArray[2][1];
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```
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