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* feat: first draft of action and cypress spec * feat: test all generated challenges * fix: better identification of block * action: update cypress config * action: upload to dashboard * action: testing js cert challenges * fix: unnecessary after user code for Make a Person * feat: capture console log output for assert test * fix: remove after seed code * fix: change const to let * fix: test * action: disable js certification * action: stop checking out branch in action * action: check out right mobile repo Co-authored-by: sembauke <semboot699@gmail.com>
119 lines
2.3 KiB
Markdown
119 lines
2.3 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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forumTopicId: 18307
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dashedName: stand-in-line
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---
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# --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 queue and old items are taken off from the front of the queue.
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# --instructions--
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Write a function `nextInLine` which takes an array (`arr`) and a number (`item`) 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 `nextInLine` function should then return the element that was removed.
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# --hints--
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`nextInLine([], 5)` should return a number.
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```js
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assert.isNumber(nextInLine([], 5));
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```
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`nextInLine([], 1)` should return `1`
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```js
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assert(nextInLine([], 1) === 1);
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```
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`nextInLine([2], 1)` should return `2`
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```js
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assert(nextInLine([2], 1) === 2);
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```
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`nextInLine([5,6,7,8,9], 1)` should return `5`
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```js
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assert(nextInLine([5, 6, 7, 8, 9], 1) === 5);
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```
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After `nextInLine(testArr, 10)`, `testArr[4]` should be `10`
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```js
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nextInLine(testArr, 10);
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assert(testArr[4] === 10);
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```
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# --seed--
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## --before-user-code--
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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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## --after-user-code--
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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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## --seed-contents--
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```js
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function nextInLine(arr, item) {
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// Only change code below this line
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return item;
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// Only change code above this line
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}
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// Setup
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let 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));
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console.log("After: " + JSON.stringify(testArr));
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```
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# --solutions--
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```js
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let 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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