private void removeNode(DoublyLinkedListNode node){
        DoublyLinkedListNode prev = node.prev;
        DoublyLinkedListNode next = node.next;
        if(prev == null){
            head = next;
        }else{
            prev.next = next;
        }

        if(next == null){
            end = prev;
        }else{
            next.prev = prev;
        }
    }