#include "Vstack.h"
#ifndef TONYLSTACK
#define TONYLSTACK 1
template<class T>
    class Link_stack : public Gstack<T> {
    	struct node {
    		T data;
    		node* next;
    		node(T d, node* n) 
    			{ data = d; next = n; }
    	};
    	node* top;
    public:
    	Link_stack( );
    	void push(T );
    	T pop();
    	bool isempty() ;
    	bool isfull() ;
    };
#endif