74 lines
1.3 KiB
Markdown
74 lines
1.3 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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videoUrl: 'https://scrimba.com/c/c8QbnCM'
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forumTopicId: 18220
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dashedName: iterate-with-javascript-while-loops
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---
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# --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 `while` 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 `while` loop will execute 5 times and append the numbers 0 through 4 to `ourArray`.
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Let's try getting a while loop to work by pushing values to an array.
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# --instructions--
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Add the numbers 5 through 0 (inclusive) in descending order to `myArray` using a `while` loop.
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# --hints--
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You should be using a `while` loop for this.
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```js
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assert(code.match(/while/g));
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```
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`myArray` should equal `[5,4,3,2,1,0]`.
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```js
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assert.deepEqual(myArray, [5, 4, 3, 2, 1, 0]);
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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 myArray;})();}
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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 = [];
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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 = [];
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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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