class Queue {
    private items :any[] = [];
    enqueue(...items:any[]){
        this.items = this.items.concat(items);
    }
    dequeue():any{
        return this.items.shift();
    }
    front():any{
        return this.items[0];
    }
    isEmpty():boolean{
        return this.items.length === 1;
    }
    size():number{
        return this.items.length;
    }
    print(){
        console.log(this.items.toString());
    }
}

interface Node {
    element: any;
    next: any;
}

class LinkedList {
    private length:number = 0;
    private list:any = null;
    getNode(element:any):Node{
        return {
            element,
            next: null
        }
    }
    append(element:any){
        let node = this.getNode(element);
        if(!this.list){
            this.list = node;
        }else{
            let current = this.list;
            while(current.next){
                current = current.next;
            }
            current.next = node;
        }
        this.length++;
    }
    insert(position:number, element:any){
        let node = this.getNode(element),
            current = this.list;
        if(this.length >= position){
            if(position === 0){
                node.next = current;
                this.list = node;
            }else{
                let previous = null;
                for(let i=0; i<position; i++){
                    previous = current;
                    current = current.next;
                }
                previous.next = node;
                node.next = current;
            }
            this.length++;
        }else{
            this.append(element);
        }
    }
    removeAt(position:number){
        if(position === 0){
            this.list = this.list.next;
        }else{
            let previous = this.list;
            for(let i=0; i<position-1; i++){
                previous = previous.next;
            }
            let next = previous.next.next;
            previous.next = next;
        }
        this.length--;
    }
    remove(element:any){
        this.removeAt(this.indexOf(element));
    }
    indexOf(element:any):number{
        var index = 0,
            current = this.list;
        while(element !== current.element){
            index++;
            current = current.next;
        }
        return index;
    }
    isEmpty():boolean{
        return this.length === 0;
    }
    size():number{
        return this.length;
    }
    getHead():object{
        return this.list;
    }
    toString():string{
        let string = '',
            current = this.list;
        if(current){
            string += current.element;
            while(current.next){
                current = current.next;
                string += current.element;
            }
        }
        return string;
    }
    print(){
        console.log(this.toString());
    }
}

// 测试代码
var linkedList = new LinkedList();
linkedList.print();
linkedList.append(1);
linkedList.print();
linkedList.append(2);
linkedList.print();
linkedList.append(3);
linkedList.print();
linkedList.append(5);
linkedList.print();
linkedList.insert(3, 4);
linkedList.print();
console.log(linkedList.indexOf(4));
linkedList.remove(4);
linkedList.print();
linkedList.removeAt(3);
linkedList.print();
console.log(linkedList.size());
linkedList.getHead();

element1.addEventListener('click',doSomething1,true)    // 捕获阶段触发
element2.addEventListener('click',doSomething2,false)    // 冒泡阶段触发

element.attachEvent("onclick", doSomething);