1 #include<stdio.h>
 2 #include<stdlib.h>
 3 typedef struct Node{
 4     int data;
 5     Node*pre,*next;
 6 }Node,*LinkList;
 7 CreateLinkList(LinkList*L)
 8 {
 9     *L=(LinkList)malloc(sizeof(Node));
10     Node*t,*r;
11     int length,e;
12     scanf("%d",&length);
13     r=*L;
14     for(int i=1;i<=length;i++)
15     {
16         scanf("%d",&e);
17         t=(LinkList)malloc(sizeof(Node));
18         t->data=e;
19         r->next=t;
20         t->pre=r;
21         r=t;
22     }
23     r->next=*L;
24     (*L)->pre=r;
25 }
26 ReSet(LinkList L)
27 {
28     Node*t,*tnext;//遍历原表L 
29     Node*left,*right;//分别从头部与尾部插入奇、偶结点 
30     int i=1;
31     left=L,right=L;
32     t=L->next;
33     while(t!=L)
34     {
35         tnext=t->next;
36         if(i%2==0)
37         {
38             right->pre=t;
39             t->next=right;
40             right=t;
41         }
42         else
43         {
44             left->next=t;
45             t->pre=left;
46             left=t;
47         }
48         i++;
49         t=tnext;    
50     }
51     left->next=right;
52     right->pre=left;
53 }
54 Order(LinkList L)
55 {
56     Node*t=L->next;
57     while(t!=L)
58     {
59         printf("%d ",t->data);
60         t=t->next;
61     }
62 }
63 int main()
64 {
65     LinkList L;
66     CreateLinkList(&L);
67     ReSet(L);
68     Order(L);
69     return 0;
70 }