程序代码：

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

typedef char ElemType;
typedef struct lsnode
{
    ElemType data;    /* 存储结点数据 */
    struct lsnode *next;    /* 指针域 */
}LinkStack;

void InitStack(LinkStack *&ls)
{
    ls=NULL;
}

void Push(LinkStack *&ls,ElemType x)
{
    LinkStack *p;
    p=(LinkStack *)malloc(sizeof(LinkStack));
    p->data=x;
    p->next=ls;
    ls=p;
}

int Pop(LinkStack *&ls,ElemType &x)
{
    LinkStack *p;
    if(ls==NULL)
        return 0;
    else
    {
        p=ls;
        x=p->data;
        ls=p->next;
        free(p);
        return 1;
    }
}

int GetTop(LinkStack *ls,ElemType &x)
{
    if(ls==NULL)
        return 0;
    else
    {
        x=ls->data;
        return 1;
    }
}

int StackEmpty(LinkStack *ls)
{
    if(ls==NULL)
        return 1;
    else
        return 0;
}

void main()
{
    LinkStack *ls;
    ElemType e;
    InitStack(ls);
    cout<<" 栈";
    if(StackEmpty(ls)==1)
        cout<<" 空"<<endl;
    else
        cout<<" 不空"<<endl;
    cout<<" a进栈"<<endl;Push(ls,'a');
    cout<<" b进栈"<<endl;Push(ls,'b');
    cout<<" c进栈"<<endl;Push(ls,'c');
    cout<<" d进栈"<<endl;Push(ls,'d');
    cout<<" 栈";
    if(StackEmpty(ls)==1)
        cout<<" 空"<<endl;
    else
        cout<<" 不空"<<endl;
    GetTop(ls,e);
    cout<<" 栈顶元素"<<e<<endl;
    cout<<" 出栈次序:";
    while(!StackEmpty(ls))
    {
        Pop(ls,e);
        cout<<e;
    }
    cout<<'\n';
}