栈的实现方式之二：链表实现的链式栈

#include <iostream>
#include <assert.h>
using namespace std;



//结点类
template< class T >

class LinkStackNode
{
public:
    T data;
    LinkStackNode< T >* link;
    LinkStackNode(T& value):data( value ),link( NULL ) {}
};


//栈类
template< class T >
class LinkStack
{
    LinkStackNode< T >* tos;
public:
    LinkStack():tos( NULL ){}
    void Push( T& value );
    T Pop();
    bool IsEmpty();
    void ClearEmpty();
};

template< class T >
void LinkStack< T >::Push( T& value )
{
    LinkStackNode< T >* add = new LinkStackNode< T >( value );
    add->data = value;
    add->link = tos;
    tos = add;
}

template< class T >
T LinkStack< T >::Pop()
{
    assert( NULL );
    LinkStackNode< T >* old = tos;
    T data1 = old->data;
    tos = tos->link;

    delete old;

    return data1;
}

template< class T >
bool LinkStack< T >::IsEmpty()
{
    if( NULL == tos )
        return true;
    else
        return false;
}

template< class T >
void LinkStack< T >::ClearEmpty()
{
    tos == NULL;
}