| digraph g { | |
| graph[rankdir="LR" dpi=300]; | |
| node[shape=circle]; | |
| n1 [label="●"]; | |
| t1 [shape=rect height=0.4 width=0.03 color=black bgcolor=black label="" style=filled xlabel=<b<SUB>l</SUB>(x)>]; | |
| t2 [shape=rect height=0.4 width=0.03 color=black bgcolor=black label="" style=filled xlabel=<u<SUB>l</SUB>(x)>]; | |
| n2 [label=" "]; | |
| n1 -> t1; | |
| {rank = same; t1 -> t2 [style=invis]}; | |
| t2 -> n1; | |
| t1 -> n2; | |
| n2 -> t2; | |
| } | |