ee1e8abd87
* feat(tools): add seed/solution restore script * chore(curriculum): remove empty sections' markers * chore(curriculum): add seed + solution to Chinese * chore: remove old formatter * fix: update getChallenges parse translated challenges separately, without reference to the source * chore(curriculum): add dashedName to English * chore(curriculum): add dashedName to Chinese * refactor: remove unused challenge property 'name' * fix: relax dashedName requirement * fix: stray tag Remove stray `pre` tag from challenge file. Signed-off-by: nhcarrigan <nhcarrigan@gmail.com> Co-authored-by: nhcarrigan <nhcarrigan@gmail.com>
90 lines
1.9 KiB
Markdown
90 lines
1.9 KiB
Markdown
---
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id: 56bbb991ad1ed5201cd392ca
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title: Access Array Data with Indexes
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/cBZQbTz'
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forumTopicId: 16158
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dashedName: access-array-data-with-indexes
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---
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# --description--
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We can access the data inside arrays using <dfn>indexes</dfn>.
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Array indexes are written in the same bracket notation that strings use, except that instead of specifying a character, they are specifying an entry in the array. Like strings, arrays use <dfn>zero-based</dfn> indexing, so the first element in an array has an index of `0`.
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<br>
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**Example**
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```js
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var array = [50,60,70];
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array[0]; // equals 50
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var data = array[1]; // equals 60
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```
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**Note**
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There shouldn't be any spaces between the array name and the square brackets, like `array [0]`. 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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Create a variable called `myData` and set it to equal the first value of `myArray` using bracket notation.
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# --hints--
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The variable `myData` should equal the first value of `myArray`.
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```js
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assert(
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(function () {
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if (
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typeof myArray !== 'undefined' &&
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typeof myData !== 'undefined' &&
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myArray[0] === myData
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) {
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return true;
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} else {
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return false;
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}
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})()
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);
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```
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The data in variable `myArray` should be accessed using bracket notation.
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```js
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assert(
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(function () {
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if (code.match(/\s*=\s*myArray\[0\]/g)) {
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return true;
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} else {
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return false;
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}
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})()
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);
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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" && typeof myData !== "undefined"){(function(y,z){return 'myArray = ' + JSON.stringify(y) + ', myData = ' + JSON.stringify(z);})(myArray, myData);}
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```
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## --seed-contents--
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```js
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// Setup
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var myArray = [50,60,70];
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// Only change code below this line
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```
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# --solutions--
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```js
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var myArray = [50,60,70];
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var myData = myArray[0];
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```
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