【动手敲代码】：链式栈（C++）

#include<iostream>
template<class T> class LinkStack;

template<class T> class StackNode
{
    private:
    T data;
    StackNode<T>* next;
    public:
    friend class LinkStack<T>;
    StackNode(T item, StackNode<T>* n = NULL):data(item),next(n){}
    T GetData(){    return data;    }
};

template<class T> 
class LinkStack
{
    private:
    StackNode<T>* top;
    public:
    LinkStack<T>():top(NULL){}
    ~LinkStack<T>()
    {    Destroy();    }
    void Destroy();
    void Push(const T item);
    T Pop();
    StackNode<T>* GetTop() const;
    void disp();
    bool IsEmpty() const
    {    return top == NULL;    }
};

template<class T>
void LinkStack<T>::Push(const T item)
{   top = new StackNode<T>(item,top);    }

template<class T>
T LinkStack<T>::Pop()
{
    if(IsEmpty())
    std::cout <<" Stack is empty " << std::endl;
    T item = top->GetData();
    StackNode<T>* remove = top;
    top = top->next;
    delete remove;
    return item; 
}

template<class T>
StackNode<T>* LinkStack<T>::GetTop() const
{   return top;    }

template<class T>
void LinkStack<T>::disp()
{
    StackNode<T>* temp = top;
    std::cout << "*****显示数据*****" << std::endl;
    while(temp)
    {
    std::cout << temp->GetData() << std::endl;
    temp = temp->next;
    }
    std::cout << "*****显示完毕*****" << std::endl;
}

template<class T>
void LinkStack<T>::Destroy()
{
    StackNode<T>* temp;
    while(top)
    {
    temp = top;
    top = top->next;
    delete temp;
    }
}