freeCodeCamp/curriculum/challenges/chinese/08-coding-interview-prep/data-structures/perform-a-subset-check-on-t...

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---
id: 587d8254367417b2b2512c6f
title: Perform a Subset Check on Two Sets of Data
challengeType: 1
videoUrl: ''
localeTitle: 对两组数据执行子集检查
---
## Description
<section id="description">在本练习中我们将对2组数据执行子集测试。我们将在我们的<code>Set</code>数据结构上创建一个名为<code>subset</code> 。这将比较第一组与第二组如果第一组完全包含在第二组中则它将返回true。例如如果<code>setA = [&#39;a&#39;,&#39;b&#39;]</code><code>setB = [&#39;a&#39;,&#39;b&#39;,&#39;c&#39;,&#39;d&#39;]</code> 则setA和setB的子集为 <code>setA.subset(setB)</code>应该是<code>true</code></section>
## Instructions
<section id="instructions">
</section>
## Tests
<section id='tests'>
```yml
tests:
- text: 你的<code>Set</code>类应该有一个<code>union</code>方法。
testString: 'assert(function(){var test = new Set(); return (typeof test.subset === "function")}, "Your <code>Set</code> class should have a <code>union</code> method.");'
- text: 第一个Set包含在第二个Set中
testString: 'assert(function(){var setA = new Set(); var setB = new Set(); setA.add("a"); setB.add("b"); setB.add("c"); setB.add("a"); setB.add("d"); var subsetSetAB = setA.subset(setB);return (subsetSetAB === true)}, "The first Set() was contained in the second Set");'
- text: '<code>[&quot;a&quot;, &quot;b&quot;].subset([&quot;a&quot;, &quot;b&quot;, &quot;c&quot;, &quot;d&quot;])</code>应该返回<code>true</code> “)'
testString: 'assert(function(){var setA = new Set(); var setB = new Set(); setA.add("a"); setA.add("b"); setB.add("a"); setB.add("b"); setB.add("c"); setB.add("d"); var subsetSetAB = setA.subset(setB); return (subsetSetAB === true)}, "<code>["a", "b"].subset(["a", "b", "c", "d"])</code> should return <code>true</code>");'
- text: '<code>[&quot;a&quot;, &quot;b&quot;, &quot;c&quot;].subset([&quot;a&quot;, &quot;b&quot;])</code>应返回<code>false</code> “)'
testString: 'assert(function(){var setA = new Set(); var setB = new Set(); setA.add("a"); setA.add("b"); setA.add("c"); setB.add("a"); setB.add("b"); var subsetSetAB = setA.subset(setB); return (subsetSetAB === false)}, "<code>["a", "b", "c"].subset(["a", "b"])</code> should return <code>false</code>");'
- text: '<code>[].subset([])</code>应该返回<code>true</code>'
testString: 'assert(function(){var setA = new Set(); var setB = new Set(); var subsetSetAB = setA.subset(setB); return (subsetSetAB === true)}, "<code>[].subset([])</code> should return <code>true</code>");'
- text: '<code>[&quot;a&quot;, &quot;b&quot;].subset([&quot;c&quot;, &quot;d&quot;])</code>应返回<code>false</code> “)'
testString: 'assert(function(){var setA = new Set(); var setB = new Set(); setA.add("a"); setA.add("b"); setB.add("c"); setB.add("d"); var subsetSetAB = setA.subset(setB); return (subsetSetAB === false)}, "<code>["a", "b"].subset(["c", "d"])</code> should return <code>false</code>");'
```
</section>
## Challenge Seed
<section id='challengeSeed'>
<div id='js-seed'>
```js
function Set() {
// the var collection will hold the set
var collection = [];
// this method will check for the presence of an element and return true or false
this.has = function(element) {
return (collection.indexOf(element) !== -1);
};
// this method will return all the values in the set
this.values = function() {
return collection;
};
// this method will add an element to the set
this.add = function(element) {
if(!this.has(element)){
collection.push(element);
return true;
}
return false;
};
// this method will remove an element from a set
this.remove = function(element) {
if(this.has(element)){
var index = collection.indexOf(element);
collection.splice(index,1);
return true;
}
return false;
};
// this method will return the size of the collection
this.size = function() {
return collection.length;
};
// this method will return the union of two sets
this.union = function(otherSet) {
var unionSet = new Set();
var firstSet = this.values();
var secondSet = otherSet.values();
firstSet.forEach(function(e){
unionSet.add(e);
});
secondSet.forEach(function(e){
unionSet.add(e);
});
return unionSet;
};
// this method will return the intersection of two sets as a new set
this.intersection = function(otherSet) {
var intersectionSet = new Set();
var firstSet = this.values();
firstSet.forEach(function(e){
if(otherSet.has(e)){
intersectionSet.add(e);
}
});
return intersectionSet;
};
// this method will return the difference of two sets as a new set
this.difference = function(otherSet) {
var differenceSet = new Set();
var firstSet = this.values();
firstSet.forEach(function(e){
if(!otherSet.has(e)){
differenceSet.add(e);
}
});
return differenceSet;
};
// change code below this line
// change code above this line
}
```
</div>
</section>
## Solution
<section id='solution'>
```js
// solution required
```
</section>