优先级队列

template<typename Type,typename Cmp> class PriorityQueue;

template<typename Type,typename Cmp> class QueueNode{
private:
	friend class PriorityQueue<Type,Cmp>;
	QueueNode(const Type item,QueueNode<Type,Cmp> *next=NULL)
		:m_data(item),m_pnext(next){}
private:
	Type m_data;
	QueueNode<Type,Cmp> *m_pnext;
};

template<typename Type> class Compare{	//处理一般比较大小
public:
	static bool lt(Type item1,Type item2);
};

template<typename Type> bool Compare<Type>::lt(Type item1, Type item2){
	return item1<item2;
}

struct SpecialData{
	friend ostream& operator<<(ostream& ,SpecialData &);
	int m_ntenor;
	int m_npir;
};

ostream& operator<<(ostream& os,SpecialData &out){
	os<<out.m_ntenor<<"   "<<out.m_npir;
	return os;
}

class SpecialCmp{		//处理特殊比较大小,用户可添加适当的类
public:
	static bool lt(SpecialData item1,SpecialData item2);
};

bool SpecialCmp::lt(SpecialData item1, SpecialData item2){
	return item1.m_npir<item2.m_npir;
}

#include "QueueNode.h"
#include "Compare.h"

template<typename Type,typename Cmp> class PriorityQueue{	//Cmp is Designed for compare
public:
	PriorityQueue():m_prear(NULL),m_pfront(NULL){}
	~PriorityQueue(){
		MakeEmpty();
	}

	void MakeEmpty();               //make the queue empty
	void Append(const Type item);   //insert data
	Type Delete();                  //delete data
	Type GetFront();                //get data
    void Print();                   //print the queue
        
	bool IsEmpty() const{           
		return m_pfront==NULL;
	}
	

private:
	QueueNode<Type,Cmp> *m_prear,*m_pfront;
};

template<typename Type,typename Cmp> void PriorityQueue<Type,Cmp>::MakeEmpty(){
	QueueNode<Type,Cmp> *pdel;
	while(m_pfront){
		pdel=m_pfront;
		m_pfront=m_pfront->m_pnext;
		delete pdel;
	}
}

template<typename Type,typename Cmp> void PriorityQueue<Type,Cmp>::Append(const Type item){
	if(m_pfront==NULL){
		m_pfront=m_prear=new QueueNode<Type,Cmp>(item);
	}
	else{
		m_prear=m_prear->m_pnext=new QueueNode<Type,Cmp>(item);
	}
}

template<typename Type,typename Cmp> Type PriorityQueue<Type,Cmp>::Delete(){
	if(IsEmpty()){
		cout<<"There is no elements!"<<endl;
		exit(1);
	}
	QueueNode<Type,Cmp> *pdel=m_pfront,*pmove=m_pfront;
	while(pmove->m_pnext){  //get the minimize priority's data

        //cmp:: lt is used for compare the two data, if the front one 
        //      is less than the back, then return 1
		if(Cmp::lt(pmove->m_pnext->m_data,pdel->m_pnext->m_data)){
			pdel=pmove;
		}
		pmove=pmove->m_pnext;
	}

	pmove=pdel;
	pdel=pdel->m_pnext;
	pmove->m_pnext=pdel->m_pnext;
	Type temp=pdel->m_data;
	delete pdel;
	return temp;
}

template<typename Type,typename Cmp> Type PriorityQueue<Type,Cmp>::GetFront(){
	if(IsEmpty()){
		cout<<"There is no elements!"<<endl;
		exit(1);
	}
	QueueNode<Type,Cmp> *pdel=m_pfront,*pmove=m_pfront->m_pnext;
	while(pmove){   //get the minimize priority's data
		if(Cmp::lt(pmove->m_data,pdel->m_data)){
			pdel=pmove;
		}
		pmove=pmove->m_pnext;
	}
	return pdel->m_data;
}

template<typename Type,typename Cmp> void PriorityQueue<Type,Cmp>::Print(){
	QueueNode<Type,Cmp> *pmove=m_pfront;
	cout<<"front";

	while(pmove){
		cout<<"--->"<<pmove->m_data;
		pmove=pmove->m_pnext;
	}

	cout<<"--->rear"<<endl<<endl<<endl;
}

#include <iostream>
#include <cstdlib>
using namespace std;

#include "PriorityQueue.h"

int main(){
	PriorityQueue<int,Compare<int> > queue;
	int init[10]={1,9,3,5,0,8,2,4,6,7};
	for(int i=0;i<10;i++){
		queue.Append(init[i]);
	}
	queue.Print();

	queue.Delete();

	queue.Print();

	system("pause");
	system("cls");
	
	PriorityQueue<SpecialData,SpecialCmp> spe_queue;
	int init2[5][2]={{34,2},{64,1},{18,3},{24,2},{55,4}};
	SpecialData data[5];
	for(int i=0;i<5;i++){
		data[i].m_npir=init2[i][1];
		data[i].m_ntenor=init2[i][0];
	}
	for(int i=0;i<5;i++){
		spe_queue.Append(data[i]);
	}
	spe_queue.Print();

    cout<<spe_queue.GetFront()<<endl<<endl;
	spe_queue.Delete();
	spe_queue.Print();
	
	
	return 0;
}