private Node<E> nextNonmarker() {
            Node<E> f = getNext();
            return (f == null || !f.isMarker()) ? f : f.getNext();
        }
private Node<E> nextNonmarker() {
            Node<E> f = getNext();
            return (f == null || !f.isMarker()) ? f : f.getNext();
        }
private Node < E > nextNonmarker ( ) { Node < E > f = getNext ( ) ; return ( f == null || ! f . isMarker ( ) ) ? f : f . getNext ( ) ; }
Returns next node, ignoring deletion marker.
Returns next node ignoring deletion marker .