双向链表实现访问频度递减

#include <cstdlib>
typedef int ElemType;
typedef struct DNode//定义双链表节点类型 
{ ElemType  data;
  ElemType  freq;
  struct DNode  *prior,*next; 
}DLinkList;
bool InitList_DuL(DLinkList *&L)
{
  L=(DLinkList *)malloc(sizeof(DLinkList));
  if(L==NULL)
	  return false;
  L->prior=L->next=L;
  return true;
}
bool Creat_DuL(DLinkList *&L,ElemType a[],int n)
{
  DLinkList *s;
  bool k=InitList_DuL(L);
  if (!k) 
	  return false;
  for(int i=0;i<n;i++)
  {
     s=(DLinkList *)malloc(sizeof(DLinkList));
	 s->data=a[i];
	 s->next=L;
	 s->prior=L->prior;
	 L->prior->next=s;
	 L->prior=s;
  }
  return true;

}
bool Locate_DuL(DLinkList *L,ElemType e,DLinkList *&p)
{
	p=L->prior;
	while(p!=L && p->data!=e)
		p=p->prior;
	if(p==L)
		return false;
	else
	    return true;
}
void Insert_DuL(DLinkList *&L,DLinkList *p,ElemType e1,ElemType e2)
{
   DLinkList *s;
   s=(DLinkList *)malloc(sizeof(DLinkList));
   s->data=e1;
   s->next=p;
   s->prior=p->prior;
   p->prior->next=s;
   p->prior=s;
   s=(DLinkList *)malloc(sizeof(DLinkList));
   s->data=e2;
   s->next=p->next;
   s->prior=p;
   p->next->prior=s;
   p->next=s;
}
void Delete_DuL(DLinkList *&L,DLinkList *p)
{
   p->prior->next=p->next ;
   p->next->prior=p->prior;
   free(p);
}
bool symmetry(DLinkList *L)
{
	DLinkList *p,*q;
	p=L->next;q=L->prior;
	while(p!=q && q->next!=p)
		if(p->data==q->data)
		{
		  p=p->next;q=q->prior;
		}
		else
		  return false;
	return true;
}
//实现访问频度递减功能
bool LocateNode(DLinkList *L,ElemType x)
{
	DLinkList *p=L->next,*q;
	while(p!=NULL&&p->data!=x)
	{
		p=p->next;
			if(p==NULL)
		return false;
	
	if(p==NULL)
		return false;
	else
		p->freq++;
	    q=p->prior;
	while(q->freq<p->freq)
	{
		p->prior=q->prior;p->prior->next=p;
		q->next=p->next;
		if(q->next!=NULL)
			q->next->prior=q;
		p->next=q;q->prior=p;
		q=p->prior;
	}
	return true;
}
}
int main()
{
    DLinkList *L,*p;
	ElemType a[]={11,22,33,44,55,66,77};
	
	bool b=Creat_DuL(L,a,7);
	LocateNode(L,33);
	LocateNode(L,22);
    LocateNode(L,33);
	b=symmetry(L);
	b=Locate_DuL(L,44,p);
	Insert_DuL(L,p,100,200);
	Delete_DuL(L,p);	
}