76 lines
2.3 KiB
Markdown
76 lines
2.3 KiB
Markdown
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---
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id: 587d8253367417b2b2512c6b
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title: Remove from a Set
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challengeType: 1
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videoUrl: ''
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localeTitle: 从集合中删除
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---
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## Description
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<section id="description">在本练习中,我们将为我们的集创建一个删除函数。该函数应命名为<code>this.remove</code> 。此函数应接受一个值并检查它是否存在于集合中。如果是,请从集合中删除该值,然后返回true。否则,返回false。 </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>remove</code>方法。
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testString: 'assert((function(){var test = new Set(); return (typeof test.remove === "function")}()), "Your <code>Set</code> class should have a <code>remove</code> method.");'
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- text: 您的<code>remove</code>方法应该只删除集合中存在的项目。
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testString: 'assert.deepEqual((function(){var test = new Set(); test.add("a");test.add("b");test.remove("c"); return test.values(); })(), ["a", "b"], "Your <code>remove</code> method should only remove items that are present in the set.");'
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- text: 您的<code>remove</code>方法应从集合中删除给定的项目。
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testString: 'assert((function(){var test = new Set(); test.add("a");test.add("b");test.remove("a"); var vals = test.values(); return (vals[0] === "b" && vals.length === 1)}()), "Your <code>remove</code> method should remove the given item from the set.");'
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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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// 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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