[TS] Queue

queue.ts

class Node<T> {
  value: T
  next?: Node<T>
  constructor(value: T) {
    this.value = value
  }
}

class Queue<T> {
  private _size = 0
  private _head?: Node<T>
  private _tail?: Node<T>

  get size(): number {
    return this._size
  }

  dequeue(): T | undefined {
    if (!this._head) return
    const current = this._head
    this._head = this._head.next
    this._size -= 1
    return current.value
  }
  enqueue(item: T): void {
    const newNode = new Node(item)
    if (this._head && this._tail) {
      this._tail.next = newNode
      this._tail = newNode
    } else {
      this._head = newNode
      this._tail = newNode
    }
    this._size += 1
  }
  clear(): void {
    this._head = undefined
    this._tail = undefined
    this._size = 0
  }
}

export default Queue