list.h.bak

人工智能中的广度搜索的九宫问题 用VC实现

# ifndef list_h
# define list_h
# include <iostream.h>
# include "listnode.h"
# include <assert.h>
# include <iomanip.h>
template <class nodetype>
class list
{
public:
	list();
	~list();
	void insertfront(const nodetype &);
	void insertback(const nodetype &);
	bool removefront(nodetype &);
	bool removeback(nodetype &);
	nodetype firstvalue()  {return firstptr->data;}
	bool isempty() const;
	void print() const;
private:
	listnode<nodetype> *firstptr;
	listnode<nodetype> *lastptr;
	listnode<nodetype> *getnew(const nodetype &);
};
template <class nodetype>
list<nodetype>::list()
:firstptr(0),lastptr(0) {};
template <class nodetype>
list<nodetype>::~list()
{
	if(!isempty())
	{
		cout<<"destroying nodes"<<endl;
		listnode<nodetype> *currentptr=firstptr,*tempptr;
		while(currentptr!=0)
		{
			tempptr=currentptr;
			currentptr=currentptr->nextptr;
			delete tempptr;
		}

	}
}
template <class nodetype>
void list<nodetype>::insertfront(const nodetype & value)
{
	listnode<nodetype> *newptr=getnew(value);
	if(isempty())
		firstptr=lastptr=newptr;
	else
	{
		newptr->nextptr=firstptr;
		firstptr=newptr;
	}
}
template <class nodetype>
void list<nodetype>::insertback(const nodetype & value)
{
	listnode<nodetype> *newptr=getnew(value);
	if(isempty())
		firstptr=lastptr=newptr;
	else
	{
		lastptr->nextptr=newptr;
		lastptr=newptr;
		newptr->nextptr=NULL;
	}
}
template <class nodetype>
bool list<nodetype>::removefront( nodetype & value)
{
	if(isempty())
		return false;
	else
	{
		listnode<nodetype> *tempptr;
		value=firstptr->data;
		tempptr=firstptr;
		firstptr=firstptr->nextptr;
		delete tempptr;
		return true;
	}
}
template <class nodetype>
bool list<nodetype>::removeback( nodetype & value)
{
	if(isempty())
		return false;
	else
	{
		listnode<nodetype> *currentptr=firstptr,*tempptr=lastptr;
		if(firstptr==lastptr)
			firstptr=lastptr=NULL;
		else{
		while(currentptr->nextptr!=lastptr)
			currentptr=currentptr->nextptr;
        lastptr=currentptr;
		currentptr->nextptr=NULL;
		}
		value=tempptr->data;
		delete tempptr;
		return true;
	}
}
template <class nodetype>
bool list<nodetype>::isempty() const
{
	return firstptr==NULL;
}
template <class nodetype>
void list<nodetype>::print() const
{
	listnode<nodetype> *currentptr=firstptr;
	while(currentptr!=NULL)
	{
		cout<<currentptr->data<<setw(6);
		currentptr=currentptr->nextptr;
	}
	cout<<endl;
}
template <class nodetype>
listnode<nodetype> *list<nodetype>::getnew(const nodetype & value)
{
	listnode<nodetype> *ptrnew=new listnode<nodetype>(value);
	assert(ptrnew);
	return ptrnew;
}
# endif