class reachable_information {
public:
	Tuple<String> node_names;
	Tuple<int> node_arity;
	Dynamic_Array1<Relation> start_nodes;
	Dynamic_Array2<Relation> transitions;
};


Dynamic_Array1<Relation> *
Reachable_Nodes(reachable_information * reachable_info);

Dynamic_Array1<Relation> *
I_Reachable_Nodes(reachable_information * reachable_info);


