.

                                    H
                          o       o l         o
                        l          e H           l
                       e            o              e
                      H         l     e           H  
                      o         H    o            o
                       l          l     e            l
                        e         H o           e
                         H         l            H
                            o       e         o
                               l     H      l
                                 e  O   e