f1c9b08cf3
This includes certificates (where it does nothing), but does not include any translations.
90 lines
1.6 KiB
Markdown
90 lines
1.6 KiB
Markdown
---
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id: cf1111c1c11feddfaeb1bdef
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title: Iterate with JavaScript While Loops
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challengeType: 1
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isHidden: false
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videoUrl: 'https://scrimba.com/c/c8QbnCM'
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forumTopicId: 18220
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---
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## Description
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<section id='description'>
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You can run the same code multiple times by using a loop.
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The first type of loop we will learn is called a <code>while</code> loop because it runs "while" a specified condition is true and stops once that condition is no longer true.
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```js
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var ourArray = [];
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var i = 0;
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while(i < 5) {
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ourArray.push(i);
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i++;
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}
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```
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In the code example above, the <code>while</code> loop will execute 5 times and append the numbers 0 through 4 to <code>ourArray</code>.
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Let's try getting a while loop to work by pushing values to an array.
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</section>
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## Instructions
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<section id='instructions'>
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Add the numbers 5 through 0 (inclusive) in descending order to <code>myArray</code> using a <code>while</code> loop.
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</section>
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## Tests
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<section id='tests'>
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```yml
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tests:
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- text: You should be using a <code>while</code> loop for this.
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testString: assert(code.match(/while/g));
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- text: <code>myArray</code> should equal <code>[5,4,3,2,1,0]</code>.
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testString: assert.deepEqual(myArray, [5,4,3,2,1,0]);
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```
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</section>
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## Challenge Seed
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<section id='challengeSeed'>
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<div id='js-seed'>
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```js
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// Setup
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var myArray = [];
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// Only change code below this line
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```
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</div>
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### After Test
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<div id='js-teardown'>
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```js
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if(typeof myArray !== "undefined"){(function(){return myArray;})();}
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```
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</div>
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</section>
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## Solution
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<section id='solution'>
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```js
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var myArray = [];
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var i = 5;
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while(i >= 0) {
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myArray.push(i);
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i--;
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}
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```
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</section>
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