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ab82857ab2
* Made output for sample code in snippet clearer * Made formatting more consistent * Fixed names for formatting fix
79 lines
1.9 KiB
Markdown
79 lines
1.9 KiB
Markdown
---
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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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const 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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const subarray = arr[3];
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const nestedSubarray = arr[3][0];
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const element = arr[3][0][1];
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```
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In this example, `subarray` has the value `[[10, 11, 12], 13, 14]`,
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`nestedSubarray` has the value `[10, 11, 12]`, and `element` has the value `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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const myArray = [
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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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const myData = myArray[0][0];
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```
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# --solutions--
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```js
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const myArray = [[1, 2, 3], [4, 5, 6], [7, 8, 9], [[10, 11, 12], 13, 14]];
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const myData = myArray[2][1];
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```
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