stack.h

软件课程设计（1） 是一些非常经典的程序

//////////////////////////////////////////////////////////////////////////
/////////////////////////链式栈模板类////////////////////////////////////
//////////////////////////////////////////////////////////////////////////


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

template <class Type> class Stack;

template <class Type> class StackNode
{
	friend class Stack <Type>;
	private:
		Type data;
		StackNode <Type> * link;
		StackNode (Type d=0,StackNode<Type> *l=NULL):data(d),link(l){}
};

template <class Type> class Stack
{
	public:
		Stack():top(NULL){}
		~Stack();
		void Push(const Type &item);
		Type Pop();
		Type GetTop();
		void MakeEmpty();
		int IsEmpty() const {return top == NULL;}
	private:
		StackNode<Type> *top;
};


template <class Type> Stack<Type>::~Stack()       //清空栈
{
    StackNode<Type> * p;
	while( top != NULL){p=top;top=top->link;delete p;}
}


template <class Type> void Stack<Type>::Push(const Type &item) //压一个数据入栈
{
	top = new StackNode<Type>(item,top);
}


template <class Type> Type Stack<Type>::Pop()    //删除栈顶结点，返回被删栈顶元素的值
{
	assert(!IsEmpty());
    StackNode<Type> *p = top;
	Type retvalue = p->data;
	top = top->link;
	delete p;
	return retvalue;
}


template <class Type> Type Stack<Type>::GetTop() //返回栈顶元素的值
{
	assert(!IsEmpty());
	return top->data;
}


template <class Type> void Stack <Type>::MakeEmpty()       //清空栈
{
    StackNode<Type> * p;
	while( top != NULL){p=top;top=top->link;delete p;}
}