+---+ +---+
| F | <## | A |
+---+ +---+
# #
# #
v v
+---+ +---+
| G | | B |
+---+ +---+
# #
# #
v v
+---+ +---+
| H | | C |
+---+ +---+
# #
# #
v v
+---+ +---+
| I | | D |
+---+ +---+
#
#
v
+---+
| E |
+---+