digraph G { 0 -> 1 0 -> 2 1 -> 3 1 -> 5 1 -> 7 2 -> 4 2 -> 5 2 -> 6 2 -> 8 3 -> 9 5 -> 9 6 -> 9 7 -> 9 4 -> 10 8 -> 10 6 -> 10 }