/**

* 基于链表实现的循环队列。

*

* Author: nameczz

*/

class Node {

constructor(element) {

this.element = element

this.next = null

}

}

class CircularQueue {

constructor() {

this.head = null

this.tail = null

}

enqueue(value) {

if (this.head === null) {

this.head = new Node(value)

this.head.next = this.head

this.tail = this.head

} else {

const flag = this.head === this.tail

this.tail.next = new Node(value)

this.tail.next.next = this.head

this.tail = this.tail.next

if (flag) {

this.head.next = this.tail

}

}

}

dequeue() {

if (this.head === this.tail) {

const value = this.head.element

this.head = null

return value

} else if (this.head !== null) {

const value = this.head.element

this.head = this.head.next

this.tail.next = this.head

return value

} else {

return -1

}

}

display() {

let res = 0

console.log('-------获取dequeue元素------')

while (res !== -1) {

res = this.dequeue()

console.log(res)

}

}

}

// Test

const newCircularQueue = new CircularQueue()

// 插入元素

newCircularQueue.enqueue(1)

newCircularQueue.enqueue(2)

newCircularQueue.enqueue(3)

// 获取元素

newCircularQueue.display()

newCircularQueue.enqueue(1)

newCircularQueue.display()

// exports.CreatedStack = StackBasedLinkedList