[数据结构]双向循环链表及其基本操作

#include <iostream>
#include <cstdio>

using namespace std;

typedef int Elem;
typedef int Status;

typedef struct DulList
{
  /* data */
  Elem data;
  struct DulList *prior;
  struct DulList *next;
} DulList, *DulLinkList;

Status InitDulList(DulLinkList &L)
{
  L = new DulList;
  L->next = NULL;
  L->prior = NULL;

  return 1;
}

Status CreatDulList_H(DulLinkList &L, int num)
{
  L = new DulList;
  L->next = NULL;

  for (int i = 1; i <= num; i++)
  {
    DulList *p = new DulList;
    cin >> p->data;

    p->next = L->next;
    if (L->next)
      L->next->prior = p;
    L->next = p;
    p->prior = L;
  }

  return 1;
}

Status ShowDulList(DulLinkList &L)
{

  DulList *q = L->next;
  while (q->next)
    q = q->next;
  q->next = L->next;//怎么双向没写 我试了一下 把尾巴指向头 就循环了...

  DulList *p = L->next;

  while (p)
  {
    cout << p->data << " ";
    p = p->next;
  }

  return 1;
}

int main()
{
  DulLinkList L;

  //1
  InitDulList(L);

  //1
  CreatDulList_H(L, 3);

  //1
  ShowDulList(L);
}