boost_1_45_0/libs/graph/example/scc.dot

digraph SCC {
 node[shape=circle];
 ratio=1.2
 a
 b
 c
 d
 e
 f
 g
 h
 i
 j

 a -> b
 a -> f
 a -> h
 b -> c 
 b -> a
 c -> d 
 c -> b
 d -> e
 e -> d
 f -> g
 g -> f
 g -> d
 h -> i
 i -> h
 i -> j
 i -> e
 i -> c
}