freeCodeCamp/curriculum/challenges/chinese/08-coding-interview-prep/data-structures/perform-a-difference-on-two-sets-of-data.chinese.md

id, title, challengeType, videoUrl, localeTitle

id	title	challengeType	videoUrl	localeTitle
587d8254367417b2b2512c6e	Perform a Difference on Two Sets of Data	1		对两组数据执行差异

Description

在本练习中，我们将对两组数据进行区分。我们将在我们的Set数据结构上创建一个名为difference 。集合的差异应比较两组并返回第一组中不存在的项目。此方法应将另一个Set作为参数，并返回两个集的difference 。例如，如果setA = ['a','b','c']和setB = ['a','b','d','e'] ，则setA和setB的差异为： setA.difference(setB) = ['c'] 。

Instructions

Tests

tests:
  - text: 你的<code>Set</code>类应该有一个<code>difference</code>方法。
    testString: assert((function(){var test = new Set(); return (typeof test.difference === 'function')})());
  - text: 收回了适当的收藏
    testString: assert((function(){var setA = new Set(); var setB = new Set(); setA.add('a'); setA.add('b'); setA.add('c'); setB.add('c'); setB.add('d'); var differenceSetAB = setA.difference(setB); return (differenceSetAB.size() === 2) && DeepEqual(differenceSetAB.values(), [ 'a', 'b' ])})());

Challenge Seed

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;
    };
    // change code below this line
    // change code above this line
}

Solution

// solution required