带头结点双链表的实现

#include
#include
using namespace std;
typedef struct  dnode
{
int data;
struct dnode* prior,*next;
}dnode,*dlinklist;
bool initdlinklist( dlinklist &L)
{
    L=(dnode*)malloc(sizeof(dnode));
    if(L==NULL)
        return false;
    L->prior=NULL;
    L->next=NULL;
    return true;
}
dlinklist establishment(dlinklist &L)
{
    int x;
    dlinklist s,p=L;
    cin>>x;
    while(x!=99999)
    {
        s=(dnode*)malloc (sizeof(dnode));
        s->data=x;
        p->next=s;
        s->prior=p;
        p=s;
        cin>>x;
    }
    p->next=NULL;
    return p;
}
int main()
{
    dlinklist L;
    initdlinklist(L);
    dlinklist h=establishment(L);
    while(h!=NULL)
    {
        cout<data<<"  ";
        h=h->prior;
    }
    return 0;
}