链表逆序

list_insert :  输入node，data，其中node为指向链表头结点的指针，data为要插入到链表中的值，该函数生成新的节点保存data，并将新节点插入到链表头部。

list_display :  输入node为链表的头部，该函数顺序打印整个链表。

list_reverse :  输入node为指向链表头节点的指针，该函数将链表逆序。

list_reverserec:  该函数的功能同样是将链表逆序，不过是递归版本。

#include <stdio.h>
#include <malloc.h>

typedef struct _node {
	struct _node *m_link;
	int m_data;
}node_t;

void list_insert (node_t **node, int data) {
	node_t *tmp = (node_t*)malloc(sizeof(node_t));
	tmp->m_data = data;
	tmp->m_link = *node;
	*node = tmp;
}

void list_display (node_t *node) {
	while (node) {
		printf ("%d ", node->m_data);
		node = node->m_link;
	}
	printf ("\n");
}

void list_reverse (node_t **node) {
	node_t *mid, *pre, *post;
	pre = 0;
	mid = *node;
	while (mid) {
		post = mid->m_link;
		mid->m_link = pre;
		pre = mid;
		mid = post;
	}
	*node = pre;
}

node_t* list_reserserec (node_t *pre, node_t *node) {
	node_t *tmp;
	if (!node->m_link) {
		node->m_link = pre;
		return node;
	}
	tmp = node->m_link;
	node->m_link = pre;
	return list_reserserec (node, tmp);
}

int main (void) {
	node_t *lst = 0;
	node_t *lst1 = 0;
	list_insert (&lst, 4);
	list_insert (&lst, 8);
	list_insert (&lst, 10);
	list_insert (&lst, 1);
	
	list_display (lst);
	printf ("==\n");
	list_reverse (&lst);
	list_display (lst);

	lst1 = list_reserserec (0, lst);
	list_display (lst1);
	return 0;
}