text: #ifndef H_PCBQUEUE_H_
  #define H_PCBQUEUE_H_
  
  typedef int ID;
  class PCB;
  
  class PCBQueue {
  public:
  	PCBQueue();
  
  	~PCBQueue();
  
  	void add(PCB* pcb);
  	void remove(PCB* pcb);
  	PCB* takeFirst();
  	PCB* findPCB(ID id);
  
  	struct Elem {
  		PCB* pcb;
  		Elem* next;
  		Elem(PCB* pcb) {
  			this->pcb = pcb;
  			next = 0;
  		}
  	};
  private:
  	Elem* head;
  	Elem* tail;
  };
  
  
  #endif /* H_PCBQUEUE_H_ */
  