Add linkedlist_deque for typescript and javascript (#326)

* add linkedlist_deque for typescript and javascript

* update typescript and javascript examples for the deque.md

* keep the same name

* update the doc

* Update deque.md

---------

Co-authored-by: steak-zhuo <zhuoqinyue@gmail.com>
Co-authored-by: Yudong Jin <krahets@163.com>
This commit is contained in:
zhuoqinyue
2023-02-06 01:31:09 +08:00
committed by GitHub
parent bc88e52955
commit c4b510038c
3 changed files with 640 additions and 2 deletions

View File

@ -0,0 +1,166 @@
/**
* File: linkedlist_deque.js
* Created Time: 2023-02-04
* Author: Zhuo Qinyue (1403450829@qq.com)
*/
/* 双向链表结点 */
class ListNode {
prev; // 前驱结点引用 (指针)
next; // 后继结点引用 (指针)
val; // 结点值
constructor(val) {
this.val = val;
this.next = null;
this.prev = null;
}
}
/* 基于双向链表实现的双向队列 */
class LinkedListDeque {
front; // 头结点 front
rear; // 尾结点 rear
len; // 双向队列的长度
constructor() {
this.front = null;
this.rear = null;
this.len = 0;
}
/* 队尾入队操作 */
pushLast(val) {
const node = new ListNode(val);
// 若链表为空,则令 front, rear 都指向 node
if (this.len === 0) {
this.front = node;
this.rear = node;
} else {
// 将 node 添加至链表尾部
this.rear.next = node;
node.prev = this.rear;
this.rear = node; // 更新尾结点
}
this.len++;
}
/* 队首入队操作 */
pushFirst(val) {
const node = new ListNode(val);
// 若链表为空,则令 front, rear 都指向 node
if (this.len === 0) {
this.front = node;
this.rear = node;
} else {
// 将 node 添加至链表头部
this.front.prev = node;
node.next = this.front;
this.front = node; // 更新头结点
}
this.len++;
}
/* 队尾出队操作 */
pollLast() {
if (this.len === 0) {
return null;
}
const value = this.rear.val; // 存储尾结点值
// 删除尾结点
let temp = this.rear.prev;
if (temp !== null) {
temp.next = null;
this.rear.prev = null;
}
this.rear = temp; // 更新尾结点
this.len--;
return value;
}
/* 队首出队操作 */
pollFirst() {
if (this.len === 0) {
return null;
}
const value = this.front.val; // 存储尾结点值
// 删除头结点
let temp = this.front.next;
if (temp !== null) {
temp.prev = null;
this.front.next = null;
}
this.front = temp; // 更新头结点
this.len--;
return value;
}
/* 访问队尾元素 */
peekLast() {
return this.len === 0 ? null : this.rear.val;
}
/* 访问队首元素 */
peekFirst() {
return this.len === 0 ? null : this.front.val;
}
/* 获取双向队列的长度 */
size() {
return this.len;
}
/* 判断双向队列是否为空 */
isEmpty() {
return this.len === 0;
}
/* 打印双向队列 */
print() {
const arr = [];
let temp = this.front;
while (temp !== null) {
arr.push(temp.val);
temp = temp.next;
}
console.log("[" + arr.join(", ") + "]");
}
}
/* 初始化双向队列 */
const linkedListDeque = new LinkedListDeque();
linkedListDeque.pushLast(3);
linkedListDeque.pushLast(2);
linkedListDeque.pushLast(5);
console.log("双向队列 linkedListDeque = ");
linkedListDeque.print();
/* 访问元素 */
const peekFirst = linkedListDeque.peekFirst();
console.log("队首元素 peekFirst = " + peekFirst);
const peekLast = linkedListDeque.peekLast();
console.log("队尾元素 peekLast = " + peekLast);
/* 元素入队 */
linkedListDeque.pushLast(4);
console.log("元素 4 队尾入队后 linkedListDeque = ");
linkedListDeque.print();
linkedListDeque.pushFirst(1);
console.log("元素 1 队首入队后 linkedListDeque = ");
linkedListDeque.print();
/* 元素出队 */
const pollLast = linkedListDeque.pollLast();
console.log("队尾出队元素 = " + pollLast + ",队尾出队后 linkedListDeque = ");
linkedListDeque.print();
const pollFirst = linkedListDeque.pollFirst();
console.log("队首出队元素 = " + pollFirst + ",队首出队后 linkedListDeque = ");
linkedListDeque.print();
/* 获取双向队列的长度 */
const size = linkedListDeque.size();
console.log("双向队列长度 size = " + size);
/* 判断双向队列是否为空 */
const isEmpty = linkedListDeque.isEmpty();
console.log("双向队列是否为空 = " + isEmpty);