编写算法实现建立一个带头结点的含n个元素的双向循环链表H，并在链表H中的第i个位置插入一个元素e

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

typedef char ElemType;
typedef struct Node
{
ElemType data;
struct Node* prior;
struct Node* next;
}DListNode,*DLinkList;

int InitDList(DLinkList *head);
DListNode *GetElem(DLinkList head,int i);
void PrintDList(DLinkList head);
int CreateDList(DLinkList head,int n);
int InsertDList(DLinkList head,int i,ElemType e);

#include "双向链表.h"

int InitDList(DLinkList *head)
{
*head = (DLinkList)malloc(sizeof(DListNode));
if(!head)
{
return -1;
}
(*head)->next = *head;
(*head)->prior = *head;
return 1;
}
DListNode *GetElem(DLinkList head,int i)
{
DListNode *p;
int j = 1;
p = head->next;
while(p != head && j < i)
{
p = p->next ;
j++;
}
if(p == head || j > i)
{
return NULL;
}
return p;
}

void PrintDList(DLinkList head)
{
DListNode *p;
p = head->next;
while(p != head)
{
printf("%c",p->data);
p = p->next;
}
printf("\n");
}

int CreateDList(DLinkList head,int n)
{
DListNode *s,*q;
int i;
ElemType e;
q = head;
for(i = 1;i <= n;i++)
{
printf("请输入第%d个元素",i);
e = getchar();
s = (DLinkList)malloc(sizeof(DListNode));
s->data = e;
s->next = q->next;
q->next = s;
s->prior = q;
head->prior = s;
q = s;
getchar();
}
return 1;
}

int InsertDList(DLinkList head,int i,ElemType e)
{
DListNode *p,*s;
p = GetElem(head,i);
if(!p)
{
return 0;
}
s = (DLinkList)malloc(sizeof(DListNode));
if(!s)
{
return -1;
}
s->data = e;
s->prior = p->prior ;
p->prior ->next = s;
s->next = p;
p->prior = s;
return 1;
}

#include "双向链表.h"

int main(void)
{
DLinkList h;
int n,pos;
ElemType e;
InitDList(&h);
printf("请输入元素的个数：");
scanf("%d",&n);
getchar();
CreateDList(h,n);
printf("链表中的元素：");
PrintDList(h);
printf("请输入插入元素：");
scanf("%c",&e);
printf("请输入插入元素的位置：");
scanf("%d",&pos);
InsertDList(h,pos,e);
printf("插入元素后链表中的元素：");
PrintDList(h);
return 0;
}