409c39abf1
* feat(curriculum): Add Basic JS Scrimba links * Fix: Add missing video url. * fix: update videoUrl
119 lines
3.0 KiB
Markdown
119 lines
3.0 KiB
Markdown
---
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id: 56533eb9ac21ba0edf2244c6
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title: Stand in Line
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/ca8Q8tP'
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---
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## Description
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<section id='description'>
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In Computer Science a <dfn>queue</dfn> is an abstract <dfn>Data Structure</dfn> where items are kept in order. New items can be added at the back of the <code>queue</code> and old items are taken off from the front of the <code>queue</code>.
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Write a function <code>nextInLine</code> which takes an array (<code>arr</code>) and a number (<code>item</code>) as arguments.
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Add the number to the end of the array, then remove the first element of the array.
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The <code>nextInLine</code> function should then return the element that was removed.
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</section>
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## Instructions
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<section id='instructions'>
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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: <code>nextInLine([], 5)</code> should return a number.
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testString: assert.isNumber(nextInLine([],5), '<code>nextInLine([], 5)</code> should return a number.');
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- text: <code>nextInLine([], 1)</code> should return <code>1</code>
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testString: assert(nextInLine([],1) === 1, '<code>nextInLine([], 1)</code> should return <code>1</code>');
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- text: <code>nextInLine([2], 1)</code> should return <code>2</code>
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testString: assert(nextInLine([2],1) === 2, '<code>nextInLine([2], 1)</code> should return <code>2</code>');
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- text: <code>nextInLine([5,6,7,8,9], 1)</code> should return <code>5</code>
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testString: assert(nextInLine([5,6,7,8,9],1) === 5, '<code>nextInLine([5,6,7,8,9], 1)</code> should return <code>5</code>');
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- text: After <code>nextInLine(testArr, 10)</code>, <code>testArr[4]</code> should be <code>10</code>
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testString: nextInLine(testArr, 10); assert(testArr[4] === 10, 'After <code>nextInLine(testArr, 10)</code>, <code>testArr[4]</code> should be <code>10</code>');
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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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function nextInLine(arr, item) {
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// Your code here
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return item; // Change this line
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}
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// Test Setup
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var testArr = [1,2,3,4,5];
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// Display Code
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console.log("Before: " + JSON.stringify(testArr));
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console.log(nextInLine(testArr, 6)); // Modify this line to test
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console.log("After: " + JSON.stringify(testArr));
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```
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</div>
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### Before Test
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<div id='js-setup'>
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```js
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var logOutput = [];
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var originalConsole = console
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function capture() {
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var nativeLog = console.log;
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console.log = function (message) {
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logOutput.push(message);
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if(nativeLog.apply) {
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nativeLog.apply(originalConsole, arguments);
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} else {
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var nativeMsg = Array.prototype.slice.apply(arguments).join(' ');
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nativeLog(nativeMsg);
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}
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};
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}
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function uncapture() {
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console.log = originalConsole.log;
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}
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capture();
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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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uncapture();
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testArr = [1,2,3,4,5];
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(function() { return logOutput.join("\n");})();
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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 testArr = [ 1,2,3,4,5];
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function nextInLine(arr, item) {
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arr.push(item);
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return arr.shift();
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}
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```
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</section>
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