数据结构基础系列——链栈的实现

栈的操作只通过栈顶进行，不能越过栈顶向栈内取数据

#ifndef LinkStack_H
#define LinkStack_H

template <class T>
struct Node
{
	T data;
	Node<T>* next;
};

template <class T>
class LinkStack
{
public:
	LinkStack()
	{
		top = NULL;
	}
	~LinkStack();
	void Push(T x);//入栈
	T Pop();//出栈
	T GetTop()//取栈顶元素值
	{ 
		if(top != NULL)
			return top->data;
		else 
			return -1;
	}
	int Empty()//判断是否为空
	{
		if(!top)
			return -1;
		else 
			return 1;
	}
private:
	Node<T>* top;
};

template <class T>
T LinkStack<T>::Pop()
{
	if(!top)
		throw"下溢！";
	T j = top->data;
	Node<T>* p = top;
	top = top->next;//栈顶下移
	delete p;
	return j;
}

template <class T>
void LinkStack<T>::Push(T x)
{
	Node<T>* s = new Node<T>;
	s->data = x;
	s->next = top;
	top = s;
}

//思路错误！对栈的构造认识不够,不像单链表那样需要头结点
/*
template <class T>
LinkStack<T>::LinkStack(T a[],int n)
{
	top = new Node<T>;
	top->next = NULL;
	for(int i = 0;i<n;i++)
	{
		Node<T>* s = new Node<T>;
		s->data = a[i];
		s->next = top;
		top = s;
	}
}
*/

template <class T>
LinkStack<T>::~LinkStack()
{
	Node<T> *q;
	while(top)
	{
		q = top;
		top = q->next;
		delete q;
		q = NULL;
	}
}
#endif

.cpp验证代码

#include "stdafx.h"
#include "LinkStack.h"

#include <iostream>
using namespace std;

int _tmain(int argc, _TCHAR* argv[])
{
	int r[] = {100,80,60,40,20};
	LinkStack<int> a;

	int j = sizeof(r)/sizeof(int);
	for(int i = 0;i<j;i++)
	{
		a.Push(r[i]);
	}

	cout<<a.GetTop()<<endl;

	for(int i = 0;i<j;i++)
	{
		try
		{
			cout<<a.Pop()<<endl;
		}
		catch(char* s)
		{
			cout<<s<<endl;
		}
	}

	cout<<a.Empty()<<endl;

	try
	{
		cout<<a.Pop()<<endl;
	}
	catch(char* s)
	{
		cout<<s<<endl;
	}
	
	a.Push(326);
	cout<<a.Empty()<<endl;
	cout<<a.GetTop()<<endl;

	return 0;
}

完~