## @【数据结构】（链栈）

@【数据结构】（链栈 基本函数）

链栈基本函数定义：进栈，出栈，取栈顶元素，判栈空，输出栈内元素

#include<stdio.h>
#include<stdlib.h>
#include<iostream>

typedef int datatype;
typedef struct node
{
	datatype data;
	struct node *next;
}StackNode, *LinkStack;
using namespace std;

LinkStack Init()  //置空栈
{
	return NULL;
}
int Empty(LinkStack top)
{
	if (top == NULL) return 1;
	else return 0;
}
int Gettop(LinkStack top, datatype &x)
{
	StackNode *s = top;
	if (s == NULL) return 0;
	else
	{
		x = s->data;
		return x;
	}
}
LinkStack push(LinkStack top, datatype x)
{
	StackNode *s;
	s = (StackNode*)malloc(sizeof(StackNode));
	s->data = x;
	s->next = top; top = s;   //新结点插入链表
	return top;
}
LinkStack pop(LinkStack top, datatype *x)
{
	StackNode *s;
	if (top== NULL)  return(NULL);  //空栈，返回空

	else
	{
		*x = top->data; s = top;
		top = top->next;  free(s);
		return top;   //返回原栈顶结点数据域的值
	}
}
void OutputLinkstack(LinkStack top)
{
	StackNode *s;
	s = top;
	while(s!=NULL)
	{
		cout << s->data << "   ";
		s=s->next;
	}
	cout << endl;
}
void main()
{
	LinkStack top;
	top=Init();
	top=push(top, 1);
	top=push(top, 4);
	top=push(top, 3);
	top=push(top, 7);
	top=push(top, 9);
	cout << "初始时栈为：" << endl;
	OutputLinkstack(top);
	datatype x;
	int index;
	while (1)        //永真循环
	{
		cout << "---------------------------------------------" << endl;
		cout << "请选择操作:1：进栈" << endl;
		cout << "           2：出栈 " << endl;
		cout << "           3：获取栈顶元素 " << endl;
		cout << "           4：栈是否为空 " << endl;
		cout << "           5：输出栈内元素" << endl;
		cout << "           0：退出 " << endl;
		cout << "---------------------------------------------" << endl;
		cin >> index;

		switch (index)
		{
		case 1:
		{
			cout << "请输入x:";
			cin >> x;
			top=push(top, x); cout << x << "进栈后：";
			OutputLinkstack(top); break;
		}
		case 2:
		{
			top=pop(top,&x);
			cout <<x<< "出栈后：" << endl;
			OutputLinkstack(top); break;
		}
		case 3:
		{

			cout << "栈顶元素为：" << Gettop(top,x)<<endl;
			break;
		}
		case 4:
		{
			cout << "栈空情况（1为空，0为非空）：" << Empty(top) << endl;
			break;
		}
		case 5:
		{
			cout << "输出栈中元素：" << endl;
			OutputLinkstack(top); break;
		}
		case 0: break;
		}
	}
	system("pause");
}

测试示例：
进栈：

出栈：

判栈空：

…