/** Doubly linked list node */
class DLink<E> {
    private E element; // Value for this node
    private DLink<E> next; // Pointer to next node in list
    private DLink<E> prev; //  Pointer to previous node

    /** Constructors */
    DLink(E it, DLink<E> p,DLink<E> n)
    { element = it; prev = p; next = n; }
    DLink(DLink<E> p, DLink<E> n) { prev = p; next = n; }

    /** Get and set methods for the data members */
    DLink<E> next() { return next; }
    DLink<E>  setNext(DLink<E> nextval)
    { return next = nextval; }
    DLink<E> prev() { return prev; }
    DLink<E> setPrev(DLink<E> prevval)
    { return prev = prevval; }
    E element() { return element; }
    E setElement(E it) { return element = it; }
}