83 lines
2.1 KiB
Markdown
83 lines
2.1 KiB
Markdown
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---
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id: 8d1923c8c441eddfaeb5bdef
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title: Size of the Set
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challengeType: 1
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videoUrl: ''
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localeTitle: 套装的大小
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---
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## Description
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<section id="description">在本练习中，我们将为Set创建一个size函数。此函数应命名为<code>this.size</code> ，它应返回集合的大小。 </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>Set</code>类应该有一个<code>size</code>方法。
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testString: 'assert((function(){var test = new Set(); return (typeof test.size === "function")}()), "Your <code>Set</code> class should have a <code>size</code> method.");'
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- text: <code>size</code>方法应返回集合中的元素数。
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testString: 'assert((function(){var test = new Set(); test.add("a");test.add("b");test.remove("a");return (test.size() === 1)}()), "The <code>size</code> method should return the number of elements in the collection.");'
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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 Set() {
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// the var collection will hold the set
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var collection = [];
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// this method will check for the presence of an element and return true or false
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this.has = function(element) {
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return (collection.indexOf(element) !== -1);
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};
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// this method will return all the values in the set
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this.values = function() {
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return collection;
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};
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// this method will add an element to the set
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this.add = function(element) {
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if(!this.has(element)){
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collection.push(element);
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return true;
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}
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return false;
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};
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// this method will remove an element from a set
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this.remove = function(element) {
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if(this.has(element)){
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var index = collection.indexOf(element);
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collection.splice(index,1);
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return true;
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}
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return false;
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};
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// change code below this line
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// 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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