使用链表实现堆栈

#include <iostream>
using namespace std;

/***********************************/
/*
栈的链式存储结构实际上是一个单链表，叫链栈
插入和删除操作只能在链栈的栈顶进行
*/
/***********************************/

#define MaxSize 100

typedef struct Node
{
    int data;
    struct Node *next;
}*pLinkStack, nLinkStack;

//链表初始化，创建一个有头结点的链表
pLinkStack CreateLinkStack()
{
    pLinkStack s;
    s = new nLinkStack;
    s->next = NULL;
    return s;
}

int IsEmptyLinkStack(pLinkStack s)
{
    //判断堆栈s是否为空，若为空则返回1，否则返回0
    return (s->next == NULL);
}

void PushLinkStack(int item, pLinkStack s)
{
    //将元素item压入堆栈s
    pLinkStack tempCell;
    tempCell = new nLinkStack;
    tempCell->data = item;
    tempCell->next = s->next;
    s->next = tempCell;    //由于头结点的存在
}

int PopLinkStack(pLinkStack pS)
{
    //删除并返回堆栈s的栈顶元素
    pLinkStack firstCell;
    int topElem;
    if ( IsEmptyLinkStack(pS) )
    {
        cout << "LinkStack is empty!" << endl;
        return NULL;
    }
    else
    {
        firstCell = pS->next;
        pS->next = firstCell->next;
        topElem = firstCell->data;
        delete firstCell;
        return topElem;
    }
}