75 lines
3.9 KiB
Markdown
75 lines
3.9 KiB
Markdown
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---
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id: 587d8250367417b2b2512c60
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title: Create a Queue Class
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challengeType: 1
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videoUrl: ''
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localeTitle: 创建队列类
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---
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## Description
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<section id="description">与堆栈一样，队列是元素的集合。但与堆栈不同，队列遵循FIFO（先入先出）原则。添加到队列的元素将被推送到队列的尾部或末尾，并且只允许删除队列前面的元素。我们可以使用数组来表示队列，但就像堆栈一样，我们希望限制我们对队列的控制量。队列类的两个主要方法是enqueue和dequeue方法。 enqueue方法将元素推送到队列的尾部，dequeue方法移除并返回队列前面的元素。其他有用的方法是front，size和isEmpty方法。说明编写一个将元素推送到队列尾部的入队方法，一个删除并返回前面元素的出列方法，一个让我们看到前面元素的前方法，一个显示长度的大小方法，以及一个isEmpty方法检查队列是否为空。 </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: 您的<code>Queue</code>类应该有一个<code>enqueue</code>方法。
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testString: 'assert((function(){var test = new Queue(); return (typeof test.enqueue === "function")}()), "Your <code>Queue</code> class should have a <code>enqueue</code> method.");'
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- text: 您的<code>Queue</code>类应该有一个<code>dequeue</code>方法。
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testString: 'assert((function(){var test = new Queue(); return (typeof test.dequeue === "function")}()), "Your <code>Queue</code> class should have a <code>dequeue</code> method.");'
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- text: 您的<code>Queue</code>类应该有一个<code>front</code>方法。
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testString: 'assert((function(){var test = new Queue(); return (typeof test.front === "function")}()), "Your <code>Queue</code> class should have a <code>front</code> method.");'
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- text: 您的<code>Queue</code>类应该有一个<code>size</code>方法。
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testString: 'assert((function(){var test = new Queue(); return (typeof test.size === "function")}()), "Your <code>Queue</code> class should have a <code>size</code> method.");'
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- text: 您的<code>Queue</code>类应该有一个<code>isEmpty</code>方法。
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testString: 'assert((function(){var test = new Queue(); return (typeof test.isEmpty === "function")}()), "Your <code>Queue</code> class should have an <code>isEmpty</code> method.");'
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- text: <code>dequeue</code>方法应该删除并返回队列的前端元素
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testString: 'assert((function(){var test = new Queue(); test.enqueue("Smith"); return (test.dequeue() === "Smith")}()), "The <code>dequeue</code> method should remove and return the front element of the queue");'
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- text: <code>front</code>方法应该返回队列的front元素的值
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testString: 'assert((function(){var test = new Queue(); test.enqueue("Smith"); test.enqueue("John"); return (test.front() === "Smith")}()), "The <code>front</code> method should return value of the front element of the queue");'
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- text: <code>size</code>方法应该返回队列的长度
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testString: 'assert((function(){var test = new Queue(); test.enqueue("Smith"); return (test.size() === 1)}()), "The <code>size</code> method should return the length of the queue");'
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- text: 如果队列中有元素，则<code>isEmpty</code>方法应返回<code>false</code>
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testString: 'assert((function(){var test = new Queue(); test.enqueue("Smith"); return !(test.isEmpty())}()), "The <code>isEmpty</code> method should return <code>false</code> if there are elements in the queue");'
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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 Queue () {
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var collection = [];
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this.print = function() {
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console.log(collection);
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};
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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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</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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