为什么我在javascript中的队列数据结构的行为不应该如此

Question

class Node {
  constructor(value) {
    this.value = value;
    this.prev = null;
  }
}
class Queue {
  constructor() {
    this.front = null;
    this.rear = null;
    this.length = 0;
  }
  enqueue(value) {
    const newNode = new Node(value);
    if (this.length === 0) {
      this.front = newNode;
      this.rear = newNode;
    } else {
      this.front.prev = this.rear;
      this.rear = newNode;
    }
    this.length++;
    
    return newNode;
  }
  dequeue() {
    if (!this.front) {
      return null;
    }
    if (this.front === this.rear) {
      this.rear = null;
    } else {
      this.front = this.front.prev;
      this.length--;
    }
    return this.front;
  }
}

const myQueue = new Queue();

console.log('myQueue.enqueue(5) : ', myQueue.enqueue(5));
console.log('myQueue : ', myQueue);

console.log('myQueue.enqueue(6) : ', myQueue.enqueue(6));
console.log('myQueue : ', myQueue);

console.log('myQueue.enqueue(7) : ', myQueue.enqueue(7));
console.log('myQueue : ', myQueue);

console.log('myQueue.dequeue() : ', myQueue.dequeue());
console.log('myQueue : ', myQueue);

console.log('myQueue.dequeue() : ', myQueue.dequeue());
console.log('myQueue : ', myQueue);

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Answer 1

有两个答案部分...

1. 最初的第一个答案，
2. 和处理OP链接列表的第二个更新答案。

this.length-而不是this.length--；存在增量错误。

class Node {
  constructor(value) {
    this.value = value;
    this.prev = null;
  }
}

class Queue {
  constructor() {

    const queue = [];

    this.front = null;
    this.rear = null;
    this.length = queue.length;

    Object.defineProperty(this, 'enqueue', {
      value: function (value) {

        const node = new Node(value);
        const itemCount = queue.push(node);

        node.prev = queue[itemCount - 2] || null;

        this.front = queue[0];
        this.rear = queue[itemCount - 1];
        this.length = itemCount;

        return node;
      }
    });
    Object.defineProperty(this, 'dequeue', {
      value: function () {

        const node = queue.shift() || null;
        const itemCount = queue.length;

        this.front = queue[0] || null;
        this.rear = queue[itemCount - 1] || null;
        this.length = itemCount;

        return node;
      }
    });
  }
}

const queue = new Queue();

console.log('queue.enqueue(5) : ', queue.enqueue(5));
console.log('queue.enqueue(6) : ', queue.enqueue(6));
console.log('queue.enqueue(7) : ', queue.enqueue(7));

console.log('queue.dequeue() : ', queue.dequeue());
console.log('queue.dequeue() : ', queue.dequeue());

console.log(queue);

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