Как реализовать простую очередь в node.js?

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class Queue {
  constructor() {
    this.items = [];
  }

  enqueue(element) {
    this.items.push(element);
  }

  dequeue() {
    if (this.isEmpty()) {
      return "Queue is empty";
    }
    return this.items.shift();
  }

  isEmpty() {
    return this.items.length === 0;
  }

  size() {
    return this.items.length;
  }

  front() {
    if (this.isEmpty()) {
      return "No elements in Queue";
    }
    return this.items[0];
  }

  printQueue() {
    let str = "";
    for (let i = 0; i < this.items.length; i++) {
      str += this.items[i] + " ";
    }
    return str;
  }
}

// Пример использования:
const queue = new Queue();
console.log(queue.isEmpty()); // true

queue.enqueue(1);
queue.enqueue(2);
queue.enqueue(3);
console.log(queue.printQueue()); // 1 2 3
console.log(queue.size()); // 3
console.log(queue.isEmpty()); // false

queue.dequeue();
console.log(queue.printQueue()); // 2 3
console.log(queue.front()); // 2

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class Node {
  constructor(element) {
    this.element = element;
    this.next = null;
  }
}

class Queue {
  constructor() {
    this.head = null;
    this.tail = null;
    this.size = 0;
  }

  enqueue(element) {
    const newNode = new Node(element);

    if (this.isEmpty()) {
      this.head = newNode;
      this.tail = newNode;
    } else {
      this.tail.next = newNode;
      this.tail = newNode;
    }

    this.size++;
  }

  dequeue() {
    if (this.isEmpty()) {
      return "Queue is empty";
    }

    const removedNode = this.head;
    this.head = this.head.next;

    if (this.head === null) {
      this.tail = null;
    }

    this.size--;
    return removedNode.element;
  }

  isEmpty() {
    return this.size === 0;
  }

  size() {
    return this.size;
  }

  front() {
    if (this.isEmpty()) {
      return "No elements in Queue";
    }
    return this.head.element;
  }

  printQueue() {
    let str = "";
    let current = this.head;

    while (current) {
      str += current.element + " ";
      current = current.next;
    }

    return str;
  }
}

// Пример использования:
const queue = new Queue();
console.log(queue.isEmpty()); // true

queue.enqueue(1);
queue.enqueue(2);
queue.enqueue(3);
console.log(queue.printQueue()); // 1 2 3
console.log(queue.size()); // 3
console.log(queue.isEmpty()); // false

queue.dequeue();
console.log(queue.printQueue()); // 2 3
console.log(queue.front()); // 2