队列

简介

1 .先进先出
2 .

class Queue{
    constructor(){
        this.dataStore=[]
    }
    enqueue(el){
        return this.dataStore.push(el)
    }
    // 添加一个到队列
    dequeue(){
        return this.dataStore.shift()
    }
    // 删除队首的元素
    front(){
        return this.dataStore[0]
    }
    // 返回队首
    back(){
        return this.dataStore[this.dataStore.length-1]
    }
    toString(){
        return this.dataStore.join(" ")
    }
    isEmpty(){
        if(this.dataStore.length==0){
            return true
        }else{
            return false
        }
    }
}

var q = new Queue();
q.enqueue("Meredith");
q.enqueue("Cynthia");
q.enqueue("Jennifer");
console.log(q.toString())//Meredith Cynthia Jennifer
q.dequeue();
console.log(q.toString())//Cynthia Jennifer
console.log(q.front())//Cynthia
console.log(q.back())//Jennifer
console.log(q.enqueue('Luckfine'))
console.log(q.toString()) //Cynthia Jennifer Luckfine