digraph G { row1 [shape=none, label=""] A [label="000"] A -> Al [label="L"] Al [label="VERIFY"] A -> Ar [label="R"] Ar [label="SKIP"] B [label="001"] B -> Bl [label="L"] Bl [label="VERIFY"] B -> Br [label="R"] Br [label="VERIFY"] { rank = same; row1; A; B; } C [label="010"] C -> Cl [label="L"] Cl [label="VERIFY"] C -> Cr [label="R"] Cr [label="DESCEND"] Cr -> Crl Crl [label="..."] Cr -> Crr Crr [label="..."] D [label="011"] D -> Dl [label="L"] Dl [label="DESCEND"] Dl -> Dll Dll [label="..."] Dl -> Dlr Dlr [label="..."] D -> Dr [label="R"] Dr [label="SKIP"] E [label="100"] E -> El [label="L"] El [label="DESCEND"] El -> Ell Ell [label="..."] El -> Elr Elr [label="..."] E -> Er [label="R"] Er [label="VERIFY"] row1 -> invis [style=invis] invis [shape=none, label=""] invis -> C [style=invis] { rank = same; C; D; E; } F [label="101"] F -> Fl [label="L"] Fl [label="DESCEND"] Fl -> Fll Fll [label="..."] Fl -> Flr Flr [label="..."] F -> Fr [label="R"] Fr [label="DESCEND"] Fr -> Frl Frl [label="..."] Fr -> Frr Frr [label="..."] G [label="110"] G -> Gl [label="L"] Gl [label="SKIP"] G -> Gr [label="R"] Gr [label="VERIFY"] H [label="111"] H -> Hl [label="L"] Hl [label="SKIP"] H -> Hr [label="R"] Hr [label="DESCEND"] Hr -> Hrl Hrl [label="..."] Hr -> Hrr Hrr [label="..."] Crl -> F [style=invis] { rank = same; F; G; H; } }