From a18ed3fd6d9a38f7484b4cccfacb2626e2759bde Mon Sep 17 00:00:00 2001
From: S-N-O-R-L-A-X <S-N-O-R-L-A-X@users.noreply.github.com>
Date: Tue, 13 Dec 2022 00:01:03 +0800
Subject: [PATCH] feat: complement array_queue doc in js

---
 docs/chapter_stack_and_queue/queue.md | 75 ++++++++++++++++++++++++++-
 1 file changed, 74 insertions(+), 1 deletion(-)

diff --git a/docs/chapter_stack_and_queue/queue.md b/docs/chapter_stack_and_queue/queue.md
index b9611a3..6b949c4 100644
--- a/docs/chapter_stack_and_queue/queue.md
+++ b/docs/chapter_stack_and_queue/queue.md
@@ -718,13 +718,86 @@ comments: true
 === "JavaScript"
 
     ```js title="array_queue.js"
+    /* 基于环形数组实现的队列 */
+    class ArrayQueue {
+        queue;     // 用于存储队列元素的数组
+        front = 0;  // 头指针，指向队首
+        rear = 0;   // 尾指针，指向队尾 + 1
+        CAPACITY = 1e5;
 
+        constructor(capacity) {
+            this.queue = new Array(capacity ?? this.CAPACITY);
+        }
+
+        /* 获取队列的容量 */
+        get capacity() {
+            return this.queue.length;
+        }
+
+        /* 获取队列的长度 */
+        get size() {
+            // 由于将数组看作为环形，可能 rear < front ，因此需要取余数
+            return (this.capacity + this.rear - this.front) % this.capacity;
+        }
+
+        /* 判断队列是否为空 */
+        empty() {
+            return this.rear - this.front == 0;
+        }
+
+        /* 入队 */
+        offer(num) {
+            if (this.size == this.capacity) {
+                console.log("队列已满");
+                return;
+            }
+            // 尾结点后添加 num
+            this.queue[this.rear] = num;
+            // 尾指针向后移动一位，越过尾部后返回到数组头部
+            this.rear = (this.rear + 1) % this.capacity;
+        }
+
+        /* 出队 */
+        poll() {
+            const num = this.peek();
+            // 队头指针向后移动一位，若越过尾部则返回到数组头部
+            this.front = (this.front + 1) % this.capacity;
+            return num;
+        }
+
+        /* 访问队首元素 */
+        peek() {
+            // 删除头结点
+            if (this.empty())
+                throw new Error("The queue is empty!");
+            return this.queue[this.front];
+        }
+
+        /* 访问指定索引元素 */
+        get(index) {
+            if (index >= this.size)
+                throw new Error("Index out of bounds!");
+            return this.queue[(this.front + index) % this.capacity];
+        }
+
+        /* 返回 Array */
+        toArray() {
+            const siz = this.size;
+            const cap = this.capacity;
+            // 仅转换有效长度范围内的列表元素
+            const arr = new Array(siz);
+            for (let i = 0, j = this.front; i < siz; i++, j++) {
+                arr[i] = this.queue[j % cap];
+            }
+            return arr;
+        }
+    }
     ```
 
 === "TypeScript"
 
     ```typescript title="array_queue.ts"
-    
+
     /* 基于环形数组实现的队列 */
     class ArrayQueue {
         private queue: number[];     // 用于存储队列元素的数组