queue.h

机场系统

//处理起飞或降落的飞机队列，本题用环形队列
#ifndef QUEUE_H
#define QUEUE_H

#include <iostream>

template<class Type> class Queue;
template<class Type> 
class QueueNode
{
	friend class Queue<Type>;
	private:
		Type data;
		QueueNode<Type> *link;
		QueueNode( const Type& x , QueueNode<Type>* xqn = 0 )
			:data( x ) , link( xqn ){};
};

template<class Type> class Queue
{
	public:
		Queue()
		{
			front = rear = 0 ; 
			sizenumber = 0; 
		};

		void Add ( const Type& );
		Type* Delete( Type& );

		int GetSize();
	private:
		QueueNode<Type> *front;
		QueueNode<Type> *rear;

		int sizenumber;
};

template <class Type> 
void Queue<Type>::Add( const Type& m )             //环型队列插入操作
{
    if ( front == 0 ) 
		front = rear = new QueueNode<Type> ( m , 0 ); 
    else 
		rear = rear->link = new QueueNode<Type> ( m , 0 );
	++sizenumber;
}

template <class Type>                              //环型队列删除操作
Type* Queue<Type>::Delete( Type& dm ) 
{
    if ( front == 0 )
	{
		return 0;
	} 
    QueueNode<Type> *p = front; 
    dm = front->data; 
    front = p->link;
    delete p; 

	--sizenumber;

    return &dm; 
}

template <class Type>
int Queue<Type>::GetSize()    
{
	return sizenumber;
}

#endif