universo-platform-3d

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class QueueNode<T> {
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  private _value: T
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  public get value(): T {
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    return this._value
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  }
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  public next: QueueNode<T> | null
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  constructor(value: T) {
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    this._value = value
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    this.next = null
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  }
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}
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class Queue<T> {
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  private _first: QueueNode<T> | null = null
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  public get first(): QueueNode<T> | null {
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    return this._first
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  }
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  private _last: QueueNode<T> | null = null
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  public get last(): QueueNode<T> | null {
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    return this._last
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  }
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  private _size = 0
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  public get size(): number {
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    return this._size
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  }
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  public enqueue(value: T): number {
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    const newNode = new QueueNode(value)
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    if (!this._first) {
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      this._first = newNode
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      this._last = newNode
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    } else {
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      if (this._last) {
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        this._last.next = newNode
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      }
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      this._last = newNode
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    }
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    return this._size++
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  }
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  public dequeue(): T | null {
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    if (!this._first) {
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      return null
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    }
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    const temp = this._first
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    if (this._first === this._last) {
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      this._last = null
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    }
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    this._first = this._first.next
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    this._size--
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    return temp.value
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  }
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}
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export { Queue, QueueNode }
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