[Queue] LinkedList로 구현하기

	class Node {
	constructor(value) {
	this.value = value;
	this.next = null;
	}
	}
	class Queue {
	constructor(){
	this.first = null;
	this.last = null;
	this.length = 0;
	}
	peek() {
	return this.first
	}
	enqueue(value){
	const newNode = new Node(value);
	if (!this.first) {
	this.first = newNode;
	}
	const temp = this.last;
	newNode.next = temp;
	this.last = newNode;
	this.length++;
	return this
	}
	dequeue(){
	if (this.first === this.last) {
	return "The queue is empty, cannot dequeue anything."
	}
	let currentNode = this.last;
	let prevNode = this.last;
	while(currentNode.next) {
	if (!currentNode.next.next) {
	prevNode = currentNode;
	}
	currentNode = currentNode.next;
	}
	prevNode.next = null;
	this.first = prevNode;
	this.length--;
	return this
	}
	}
	const myQueue = new Queue();

view raw queue_by_linked_list.js hosted with ❤ by GitHub

 

	class Node {
	constructor(value) {
	this.value = value;
	this.next = null;
	}
	}
	class Queue {
	constructor(){
	this.first = null;
	this.last = null;
	this.length = 0;
	}
	peek() {
	return this.first
	}
	enqueue(value){
	const newNode = new Node(value);
	if (!this.first) {
	this.first = newNode;
	this.last = newNode;
	} else {
	this.last.next = newNode;
	this.last = newNode;
	}
	this.length++;
	return this
	}
	dequeue(){
	if (this.first === this.last) {
	this.last = null
	}
	if (this.length === 0) {
	return "The queue is empty, cannot remove anything."
	}
	// const target = this.first
	this.first = this.first.next;
	this.length--;
	// return target
	return this
	}
	//isEmpty;
	}
	const myQueue = new Queue();

view raw queue2_by_linked_list.js hosted with ❤ by GitHub