//使用javascript来实现栈的数据结构
var Stack={
    //不需要外界传参进行初始化，完全可以定义为一个属性
    items:[],
    push:function(item){
        this.items.push(item);
    },
    pop:function(){
        return this.items.pop();
    },
    peek:function(){
        ];
    },
    isEmpty:function(){
        ;
    },
    size:function(){
        return this.items.length;
    },
    clear:function(){
        this.items=[];
    },
    print:function(){
        console.log(this.items.toString());
    }
};

//基于栈的数据结构实现进制转换,比如将十进制转换为2进制
function baseConvert(number,base){
    var result=Object.create(Stack),
        rem,
        baseString='',
        digits='0123456789ABCDEF',
        decNumber=number;
    ){
        rem=Math.floor(decNumber%base);
        result.push(rem);
        decNumber=Math.floor(decNumber/base);
    }

    while(!result.isEmpty()){
        baseString+=digits[result.pop()];
    }
    return baseString;
}

console.log(baseConvert(,));//输出11000011111111001
console.log(baseConvert(,));//输出303771
console.log(baseConvert(,));//输出187F9

//实现队列
var Queue={
    item:[],
    enqueue:function(item){
        this.items.push(item);
    },
    dequeue:function(){
        return this.items.shift();
    },
    isEmpty:function(){
        ;
    },
    front:function(){
        ];
    },
    clear:function(){
        this.items=[];
    },
    size:function(){
        return this.items.length;
    }
};

//单链表的实现
//感觉在javascript中实现单链表没有什么用
//因为单链表的有事在于插入，删除元素的时间复杂度为O（1）,可以javascript中利用数组，调用数组的splice方法，就可以实现这一目的
var Node={
    init:function(element){
        this.element=element;
        this.next=null;
    },
};
var LinkedList={
    length:,
    head:null,//指向队列的头结点
    //尾部插入元素
    append:function(element){
        var node=Object.create(Node),
            current;
        node.init(element);

        if(!this.head){
            this.head=node;
        }else{
            current=this.head;
            while(current.next){
                current=current.next;
            }
            current.next=node;
        }
        this.length++;
        return true;
    },
    //在任意一个位置插入一个元素
    insert:function(position,element){
        ||position>=this.length){
            return false;
        }
        var node=Object.create(Node),
            current=this.head,
            previous=this.head,
            index=;
        node.init(element);
        ){
            node.next=this.head;
            this.head=node;
        }else{
            while(index<position){
                index++;
                previous=current;
                current=current.next;
            }
            node.next=current;
            previous.next=node;
        }
        this.length++;
        return true;
    },
    //从链表中移除元素
    removeAt:function(position){
        var current=this.head,
            previous,
            index=;
        ||position>=this.length){
            return false;
        }
        ){
            this.head=this.head.next;
        }else{
            while(index<position){
                index++;
                previous=current;
                current=current.next;
            }
            previous.next=current.next;
        }
        this.length--;
        return true;
    },

    //接收一个元素的值，如果在列表中找到它，就返回元素位置，否则返回-1
    indexOf:function(element){
        var current=this.head,
            index=;
        while(current){
            if(current.element==element){
                return index;
            }else{
                index++;
                current=current.next;
            }
        }
        ;
    },
    isEmpty:function(){
        ;
    },
    size:function(){
        return this.length;
    },
    //将LinkedList对象转换为一个字符串
    toString:function(){
        var current=this.head,
            baseStr='';
        while(current){
            baseStr+=current.element+',';
            current=current.next;
        }
        return baseStr;
    },
    print:function(){
        console.log(this.toString());
    }
};

//实现集合这种数据结构
//基本思路是基于javascript对象结构的键值来实现,当然也可以基于数组
var Set={
    init:function(){
        this.items=Object.create(null);
    },
    has:function(item){
        return item in this.items;
    },
    add:function(item){
        if(!this.has(item)){
            this.items[item]=item;
            return true;
        }
        return false;
    },
    remove:function(item){
        if(this.has(item)){
            delete this.items[item];
            return true;
        }
        return false;
    },
    clear:function(){
        this.items={};
    },
    size:function(){
        return Object.keys(this.items).length;
    },
    values:function(){
        return Object.keys(this.items);
    },
    //求并集
    union:function(otherSet){
        var result=Object.create(Set),
            key;
        result.init();
        for(key in this.items){
            result.add(key);
        }
        for(key in otherSet.items){
            result.add(key);
        }
        return result;
    },
    //求交集
    intersection:function(otherSet){
        var result=Object.create(Set),key;
        result.init();
        for(key in this.items){
            if(otherSet.has(key)){
                result.add(key);
            }
        }
        return result;
    },

};