简易栈模版（链表实现）

一个用链表写的栈的模版，只写了几个最常用的功能，对象的比较没写，就是重载运算符而已。

文件“mystack.h”

#include<iostream>
using namespace std;

template<class T>
class My_stack;

template<class T>
class Node		//结点类
{
private:
	T data;
	Node<T> *next;
public:
	Node()
	{
		next=NULL;
	}
	Node(T d)
	{
		data=d;
		next=NULL;
	}
	friend My_stack<T>;
};

template<class T>
class My_stack
{
private:
	Node<T> *head;
public:
	My_stack()
	{
		head=new Node<T>();
	}
	
	~My_stack()
	{
		clean();
		delete head;
	}

	bool empty() const
	{
		return (head->next==0);
	}

	int size() const
	{
		int length=0;
		Node<T> *p=head->next;
		while(p)
		{
			length++;
			p=p->next;
		}
		return length;
	}

	void push(T d)	//入栈
	{
		Node<T> *p=new Node<T>(d);
		p->next=head->next;
		head->next=p;
	}

	T top()	//返回栈顶元素
	{
		if(empty())
		{
			cout<<"stack is empty."<<endl;
			exit(1);
		}
		Node<T> *p=head->next;
		T temp=p->data;
		return temp;
	}

	void pop()	//弹出栈顶元素
	{
		Node<T> *p=head->next;
		head->next=p->next;
		delete p;
	}

	void clean()	//清除整个栈
	{
		Node<T> *p=head->next;
		while(p)
		{
			head->next=p->next;
			delete p;
			head->next=p;
		}
		cout<<"清理完成"<<endl;
	}
};

下面是一个测试代码

main.cpp

#include"mystack.h"
#include<string>
using namespace std;

int main()
{
	My_stack<string> s;
	if(s.empty())
		cout<<"stack is empty"<<endl;

	//cout<<s.top()<<endl;

	s.push("dan");
	s.push("liu");
	s.push("ai");
	s.push("wo");

	cout<<"Now the stack's size is: "<<s.size()<<endl;

	while(!s.empty())
	{
		cout<<s.top()<<"   ";
		s.pop();
	}
	cout<<endl;

	return 0;
}