利用链表实现栈

//利用链表构建栈。
//输入1 2 3 4 5 0时输出 5 4 3 2 1
#include<stdio.h>
#include<stdlib.h>
#define true  1
#define false 0

typedef struct node{ //建立结构体
	int num;
  	struct node *next;
}Node;

int push(Node **head, int num) //将一个数字压入以head为头的堆栈
{	
	Node *nextNode;

	if(NULL==(nextNode=(struct node *)malloc(sizeof(struct node )))){
		return false;
	}
	nextNode->num = num;
	
	if(NULL == *head){
		nextNode->next = NULL;
		*head = nextNode;
		return true;
	} 
	nextNode->next = *head;//尾插法
	*head = nextNode;
	
	return true;
}
int pop(Node **head,int *num) //出栈
{
	Node *temp;
	
	if(NULL == *head)return false;
	
	*num = (*head)->num;
	temp = (*head)->next;
	
	free(*head);
	
	*head = temp;
	
	return true;
}
int main(int argc, char* argv[]) //主函数  
{
	int n=0,num;
	Node *head;

	head=NULL;
	
	printf("Please input numbers end with 0 :\n");
	
	while(1){ //如果不是0，压栈
		scanf("%d",&num);
		if(0 == num)break;
		push(&head,num);
		n++;
	}	

	while(pop(&head,&num)){ //出栈输出
		printf("%d ", num);
	}
	printf("\nTotal : %d\n",n);
}