C 带头节点单链表逆序

#include<stdio.h>
#include<stdlib.h>


typedef struct node
{
int num;
struct node *next;
}Node;
typedef Node * Link;

void revers_list(Link  head)

{
Link p1 = NULL;
Link p2 = NULL;
Link p3 = NULL;
p3 = head->next;
if(p3 == NULL)
{
printf("list is empty!\n");
return; 
}
if(p3->next == NULL)
{
return;
}
else
{
p2 = p3->next;
if(p2->next == NULL)
{
p2->next = p3;
p3->next = NULL;
head->next = p2;
}
else
{
p1 = p2->next;
while(p1->next != NULL)
{
p2->next = p3;
p3 = p2;
p2 = p1;
p1 = p1->next;
}
p2->next = p3;
p1->next = p2;
head->next->next = NULL;
head->next = p1;
}
}


}