digraph g {

	s0 [shape="circle" label="0"];
	s1 [shape="circle" label="1"];
	s2 [shape="circle" label="2"];
	s0 -> s1 [modality="MUST" label="b"];
	s1 -> s2 [modality="MAY" style="dashed" label="b"];
	s1 -> s0 [modality="MUST" label="d"];
	s2 -> s2 [modality="MAY" style="dashed" label="b"];
	s2 -> s2 [modality="MAY" style="dashed" label="d"];

__start0 [label="" shape="none" width="0" height="0"];
__start0 -> s0;

}
