实现单向链表、队列

// 链表的节点类
class Node{
    constructor(ele,next){
        this.element = ele;
        this.next = next;
    }
}
class LinkedList{
    constructor(){
        this.head = null;
        this.size = 0;
    }
    // 私有属性、获取下标为index的节点
    _node(index){ 
        let cur = this.head;
        for(let i=0;i<index;i++){
            cur = cur.next;
        }
        return cur;
    }
    add(index,ele){ // 增
        if(typeof ele == 'undefined'){
            ele = index;
            index = this.size;
        }
        if(this.size === 0){
            let node = new Node(ele,null);
            this.head = node;
        }else{
            let preNode = this._node(index-1); // 前一位的值
            let node = new Node(ele,preNode.next);
            preNode.next = node;
        }
        this.size++;
    }
    remove(index){ // 删
        let removeNode;
        if(index == 0){
            removeNode = this.head;
            this.head = this.head.next;
        }else{
            let pre = this._node(index-1);
            removeNode = pre.next;
            pre.next = pre.next.next;
        }
        
        this.size--;
        return removeNode;
    }
    set(index,ele){ // 改
        let node = this._node(index);
        node.element = ele;
        return node;
    }
    get(index){ // 查
        return this._node(index);
    }
    revert(){
        function reverse(head){
            if(head == null || head.next == null){
                return head;
            }
            let newHead= reverse(head.next);
            head.next.next = head;
            head.next = null;
            return newHead;
        }
        this.head = reverse(this.head);
        return this.head;
    }
}


let linkedList = new LinkedList();
linkedList.add(0);
linkedList.add(2);
linkedList.add(1,1);
linkedList.add(3);
linkedList.add(4);
linkedList.add(5);
console.dir(linkedList,{depth:1000});
linkedList.remove(2);
console.dir(linkedList,{depth:1000});
linkedList.add(2,2);
console.dir(linkedList,{depth:1000});
linkedList.set(0,99);
console.dir(linkedList,{depth:1000});
module.exports = LinkedList;

const LinkedList = require('./Linkedlist');
class Queue{
    constructor(){
        this.linkedList = new LinkedList();
    }
    add(ele){
        this.linkedList.add(ele);
    }
    offer(){
        this.linkedList.remove(0);
    }
}

let queue = new Queue();
queue.add(1);
queue.add(2);
queue.add(3);
console.dir(queue,{depth:1000})
queue.offer();
console.dir(queue,{depth:1000})