89 lines
2.6 KiB
Markdown
89 lines
2.6 KiB
Markdown
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---
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id: 587d8255367417b2b2512c75
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title: Create a Circular Queue
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challengeType: 1
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videoUrl: ''
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localeTitle: ''
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---
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## Description
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undefined
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## Instructions
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undefined
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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: ''
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testString: 'assert((function(){ var test = new CircularQueue(3); test.enqueue(17); test.enqueue(32); test.enqueue(591); var print = test.print(); return print[0] === 17 && print[1] === 32 && print[2] === 591; })(), "The <code>enqueue</code> method adds items to the circular queue.");'
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- text: ''
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testString: 'assert((function(){ var test = new CircularQueue(3); test.enqueue(17); test.enqueue(32); test.enqueue(591); test.enqueue(13); test.enqueue(25); test.enqueue(59); var print = test.print(); return print[0] === 17 && print[1] === 32 && print[2] === 591; })(), "You cannot enqueue items past the read pointer.");'
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- text: ''
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testString: 'assert((function(){ var test = new CircularQueue(3); test.enqueue(17); test.enqueue(32); test.enqueue(591); return test.dequeue() === 17 && test.dequeue() === 32 && test.dequeue() === 591; })(), "The <code>dequeue</code> method dequeues items from the queue.");'
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- text: ''
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testString: 'assert((function(){ var test = new CircularQueue(3); test.enqueue(17); test.enqueue(32); test.enqueue(672); test.dequeue(); test.dequeue(); var print = test.print(); return print[0] === null && print[1] === null && print[2] === 672; })(), "After an item is dequeued its position in the queue should be reset to <code>null</code>.");'
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- text: ''
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testString: 'assert((function(){ var test = new CircularQueue(3); test.enqueue(17); test.enqueue(32); test.enqueue(591); return test.dequeue() === 17 && test.dequeue() === 32 && test.dequeue() === 591 && test.dequeue() === null && test.dequeue() === null && test.dequeue() === null && test.dequeue() === null && test.enqueue(100) === 100 && test.dequeue() === 100; })(), "Trying to dequeue past the write pointer returns <code>null</code> and does not advance the write pointer.");'
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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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class CircularQueue {
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constructor(size) {
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this.queue = [];
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this.read = 0;
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this.write = 0;
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this.max = size - 1;
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while (size > 0) {
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this.queue.push(null);
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size--;
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}
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}
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print() {
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return this.queue;
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}
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enqueue(item) {
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// Only change code below this line
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// Only change code above this line
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}
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dequeue() {
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// Only change code below this line
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// Only change code above this line
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}
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}
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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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// solution required
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```
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</section>
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