C++ 模板应用 实现一个Queue 队列

#include<iostream>
using namespace std;
template <typename T>
class Queue
{
public:
Queue()
{
Node<T> *node=new Node<T>();
node->data=NULL;
node->next=NULL;
qfront=qrear=node;
}
template <typename T>
struct Node
{
Node<T> *next;
T data;
};
bool empty() const;
void pop();
T & front();
T & back();
void push(const T &);
int size() const;
private:
Node<T> *qfront,*qrear;
};
template <typename T>
T &Queue<T>::back()
{
if(!empty())
return qrear->data;
}
template <typename T>
T &Queue<T>::front()
{
if(!empty())
{
Node<T> *p=qfront->next;
return p->data;
}
}
template <typename T>
bool Queue<T>::empty() const
{
if(qfront==qrear)
return true;
else
return false;
}
template <typename T>
void Queue<T>::pop()
{
if(!empty())
{
Node<T> *p=qfront->next;
qfront->next=p->next;
if(p==qrear)
qrear=qfront;
delete p;
p=NULL;

}
}
template<typename T>
void Queue<T>::push(const T & t)
{
Node<T> *node=new Node<T>;
node->data=t;
node->next=NULL;
qrear->next=node;
qrear=node;
}
template<typename T>
int Queue<T>::size() const
{
Node<T> *p=qfront;
if(empty())
return 0;
else
{
int i=1;
while(p->next!=qrear)
{
p=p->next;
i++;
}
return i;
}
}

int main()
{
Queue<int> q;
q.push(1);
q.push(2);
q.pop();
q.pop();
q.pop();
cout<<q.size()<<endl;
getchar();
return 0;
}