130 lines
		
	
	
		
			5.3 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
		
		
			
		
	
	
			130 lines
		
	
	
		
			5.3 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
| 
								 | 
							
								---
							 | 
						|||
| 
								 | 
							
								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 = ['a','b']</code>和<code>setB = ['a','b','c','d']</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>["a", "b"].subset(["a", "b", "c", "d"])</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>["a", "b", "c"].subset(["a", "b"])</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>["a", "b"].subset(["c", "d"])</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>
							 |