链栈的实现（双指针 带头结点） C语言版

/*
带头结点，双指针的链栈实现
作者：S_hmily
日期：2011年8月31日
编译环境：VC++6.0
*/
/*************************************************************/
#include <stdio.h>
#include <malloc.h>
#include <stdlib.h>
/*************************************************************/
#define TRUE	1
#define	FALSE	0

typedef struct node {
int		data;
struct node *pNext;
}Node, *pNode;

typedef struct{
pNode	pTop;
pNode	pBottom;
}STACK, *pSTACK;

/*************************************************************/
void init_stack(pSTACK pS);
void push_stack(pSTACK pS, int val);
int  pop_stack(pSTACK pS, int *pVal);
void traverse(pSTACK pS);
int  empty(pSTACK pS);
/*************************************************************/
int main(void)
{
STACK stack;
int val;
init_stack(&stack);
push_stack(&stack, 1);
//	traverse(&stack);
if (pop_stack(&stack, &val))
printf("出栈的元素是%d\n", val);
else
printf("栈空\n");
//	traverse(&stack);
return 0;
}

/*************************************************************/
void init_stack(pSTACK pS)
{
pS->pTop  = (pNode)malloc(sizeof(Node));
if (NULL == pS->pTop) {
printf("动态内存分配失败");
exit(-1);
}

pS->pBottom = pS->pTop;
pS->pBottom->pNext = NULL;
}

/*************************************************************/
void push_stack(pSTACK pS, int val)
{
pNode pNew = (pNode)malloc(sizeof(Node));
if (NULL ==pNew) {
printf("动态内存分配失败");
exit(-1);
}

pNew->data = val;
pNew->pNext = pS->pTop;
pS->pTop = pNew;
}

/*************************************************************/
void traverse(pSTACK pS)
{
pNode p = pS->pTop;

while (p != pS->pBottom) {
printf("%d ", p->data);
p = p->pNext;
}
}
/*************************************************************/
int  empty(pSTACK pS)
{
if (pS->pTop == pS->pBottom)
return TRUE;
else
return FALSE;
}

/*************************************************************/
int pop_stack(pSTACK pS, int *pVal)
{
pNode p = pS->pTop;

if ( empty(pS) )
return FALSE;

*pVal = p->data;
pS->pTop = p->pNext;
free(p);
p = NULL;
return TRUE;
}
/*************************************************************/