dequeue() {
    if (!this.top) {
      return "Queue empty!!! Cannot remove item...";
    }

    if (this.length === 1) {
      this.top = null;
      this.bottom = null;
    } else {
      const nextPointer = this.top.next;
      this.top = nextPointer;
    }
    this.length--;
    return this;
  }
/**
   * removes first item from queue
   *
   * @returns
   * @memberof Queue
   */
removes first item from queue
@returns
@memberof Queue
removes first item from queue @returns @memberof Queue
dequeue() {
    if (!this.top) {
      return "Queue empty!!! Cannot remove item...";
    }
    if (this.length === 1) {
      this.top = null;
      this.bottom = null;
    } else {
      const nextPointer = this.top.next;
      this.top = nextPointer;
    }
    this.length--;
    return this;
  }
dequeue ( ) { if ( ! this . top ) { return "Queue empty!!! Cannot remove item..." ; } if ( this . length === 1 ) { this . top = null ; this . bottom = null ; } else { const nextPointer = this . top . next ; this . top = nextPointer ; } this . length -- ; return this ; }
removes first item from queue
 @returns
 @memberof Queue
removes first item from queue @returns @memberof Queue