digraph foogrph {
  node [shape = record,height=.1];
  node5[label = "<left> |<center> 5|<right> "];
  "node5":left -> "node4":center;
  node4[label = "<left> |<center> 4|<right> "];
  "node4":left -> "node3":center;
  node3[label = "<left> |<center> 3|<right> "];
  "node4":right -> "node6":center;
  node6[label = "<left> |<center> 6|<right> "];
  "node5":right -> "node7":center;
  node7[label = "<left> |<center> 7|<right> "];
}