75 lines
3.9 KiB
Markdown
75 lines
3.9 KiB
Markdown
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---
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id: 587d8250367417b2b2512c5f
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title: Create a Stack Class
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challengeType: 1
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videoUrl: ''
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localeTitle: 创建一个堆栈类
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---
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## Description
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<section id="description">在上一节中，我们讨论了堆栈是什么以及如何使用数组来表示堆栈。在本节中，我们将创建自己的堆栈类。虽然您可以使用数组来创建堆栈，但有时最好限制我们对堆栈的控制量。除了<code>push</code>和<code>pop</code>方法之外，堆栈还有其他有用的方法。让我们为我们的堆栈类添加一个<code>peek</code> ， <code>isEmpty</code>和<code>clear</code>方法。说明编写一个<code>push</code>方法，将元素推送到堆栈顶部，一个<code>pop</code>方法删除堆栈顶部的元素，一个<code>peek</code>堆栈中第一个元素的<code>peek</code>方法，一个<code>isEmpty</code>方法，用于检查是否存在stack是空的，是一个<code>clear</code>堆栈中所有元素的方法。通常堆栈没有这个，但我们添加了一个控制台记录集合的<code>print</code>助手方法。 </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: 你的<code>Stack</code>类应该有一个<code>push</code>方法。
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testString: 'assert((function(){var test = new Stack(); return (typeof test.push === "function")}()), "Your <code>Stack</code> class should have a <code>push</code> method.");'
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- text: 你的<code>Stack</code>类应该有一个<code>pop</code>方法。
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testString: 'assert((function(){var test = new Stack(); return (typeof test.pop === "function")}()), "Your <code>Stack</code> class should have a <code>pop</code> method.");'
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- text: 你的<code>Stack</code>类应该有一个<code>peek</code>方法。
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testString: 'assert((function(){var test = new Stack(); return (typeof test.peek === "function")}()), "Your <code>Stack</code> class should have a <code>peek</code> method.");'
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- text: 您的<code>Stack</code>类应该有一个<code>isEmpty</code>方法。
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testString: 'assert((function(){var test = new Stack(); return (typeof test.isEmpty === "function")}()), "Your <code>Stack</code> class should have a <code>isEmpty</code> method.");'
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- text: 你的<code>Stack</code>类应该有一个<code>clear</code>方法。
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testString: 'assert((function(){var test = new Stack(); return (typeof test.clear === "function")}()), "Your <code>Stack</code> class should have a <code>clear</code> method.");'
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- text: <code>peek</code>方法应该返回堆栈的顶部元素
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testString: 'assert((function(){var test = new Stack(); test.push("CS50"); return (test.peek() === "CS50")}()), "The <code>peek</code> method should return the top element of the stack");'
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- text: <code>pop</code>方法应该删除并返回堆栈的顶部元素
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testString: 'assert((function(){var test = new Stack(); test.push("CS50"); return (test.pop() === "CS50");}()), "The <code>pop</code> method should remove and return the top element of the stack");'
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- text: 如果堆栈不包含任何元素，则<code>isEmpty</code>方法应返回true
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testString: 'assert((function(){var test = new Stack(); return test.isEmpty()}()), "The <code>isEmpty</code> method should return true if a stack does not contain any elements");'
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- text: <code>clear</code>方法应该从堆栈中删除所有元素
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testString: 'assert((function(){var test = new Stack(); test.push("CS50"); test.clear(); return (test.isEmpty())}()), "The <code>clear</code> method should remove all element from the stack");'
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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 Stack() {
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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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