struct Node{ 
public: 
   Member*      info; //type is arbitrary, to the linked list implementation 
   Node*      next; //used to point to next node 
        Node*           prev; //used to point to previous node 

   Node():prev(NULL),next(NULL) {} //default constructor 
        Node(Node* n):prev(n),next(NULL) {} //prev known constructor 
        Node(Node* n, Node* m):prev(n),next(m) {} //prev and next known constructor 
   ~Node() { delete info; delete next; } //destructor 
};

Node* head; 
head = &(new Node(&head);//create Node which knows prev(head) and next is NULL

 
Node* n = head; 
while(n->next){ 
//loop code 
n = n->next; 
}