.
            
                                     c
                             h     he    h
                           e        rr        e
                         r           y           r
                        r            c              r  
                       y             h              y
                      c              e                 c
                     h            r      r             h
                    e             y      c              e
                     r             h    e              r
                      r                r                r
                           y           r           y  
                                        y