鏈表棧（動態分配管理）

// 2013-11-5
//鏈表靜態棧
/*
*在一個棧結構體中設置兩個節點指針，分別指向棧頂和棧底
*節點是按需要新增的，所以這個棧理論上是可以很大的，與windows系統自動分配的棧有所不同
*首先要初始化棧，就是將棧頂和棧底都指向一個新造的節點，這個節點始終都存在，相當於鏈表中的頭結點，
*這個節點不放任何數據元素，只是用來管理棧的
*/
#include <stdio.h>
#include <stdlib.h>
#include <malloc.h>
#include <windows.h>


typedef struct node
{
	int data;
	struct node * pNext;
}NODE, *PNODE;
typedef struct stack
{
	PNODE top;
	PNODE bottom;
}STACK, *PSTACK;

void init(PSTACK pS);
void push(PSTACK pS, int);
bool pop(PSTACK pS, int *);
bool isempty(PSTACK pS);
void clear(PSTACK pS);
void traverse(PSTACK pS);

int main(void)
{
	int val;
	STACK s;
	
	init(&s);
	
	push(&s, 8);
	
	push(&s, 4);

	traverse(&s);

	if (pop(&s, &val))
	{
		printf("彈出成功，彈出的元素爲：%d\n", val);
	}

	traverse(&s);

	clear(&s);
	traverse(&s);


	return 0;
}

void init(PSTACK pS)
{
	pS->top = (PNODE)malloc(sizeof(NODE));
	if ( NULL == pS->top)
	{
		printf("內存分配失敗！！\n");
		exit(-1);
	}
	else
	{
		pS->bottom = pS->top;
		pS->top->pNext = NULL;
	}
}

void push(PSTACK pS, int val)
{
	PNODE pNew = (PNODE)malloc(sizeof(NODE));
	if (NULL == pNew)
	{
		printf("分配內存失敗！！\n");
		exit(-1);
	}
	pNew->data = val;
	pNew->pNext = pS->top;
	pS->top = pNew;
}

bool pop(PSTACK pS, int *pVal)
{
	if (isempty(pS))
	{
		printf("棧已經爲空了！！\n");
		return false;
	}

	else
	{
		PNODE p = pS->top;
		*pVal = p->data;
		pS->top = p->pNext;
		free(p);
		p = NULL;

		return true;
	}
	
};

void traverse(PSTACK pS)
{
	if (isempty(pS))
	{
		printf("空棧，沒有元素！！不能輸出~~~~~~~~~~\n");
		return;
	}
	else
	{
	 PNODE p = pS->top;
	 while (p != pS->bottom)
	 {
		printf("%d   ",p->data);
		p = p->pNext;
	 }
	 printf("\n");
	    return;
	}
}

bool isempty(PSTACK pS)
{
	if (pS->top == pS->bottom)
	{
		return true;
	}
	else return false;
}

void clear(PSTACK pS)
{
	PNODE p = pS->top;
	while (p != pS->bottom)
	{
		PNODE q = p->pNext;

		free(p);
		
		p = q;
	}
	pS->top = p;
}

結果顯示爲：