proposition: Lemma reachable_Same_set (g: Gph) (S1 S2 : list V): S1 ~= S2 -> Same_set (reachable_through_set g S1) (reachable_through_set g S2).
proof: Proof. intros; destruct H; split; repeat intro; destruct H1 as [y [HIn Hrch]]; exists y; split; auto. Qed.
imports: Coq.Logic.ProofIrrelevance Coq.micromega.Lia CertiGraph.lib.Coqlib CertiGraph.lib.EnumEnsembles CertiGraph.lib.List_ext CertiGraph.lib.EquivDec_ext CertiGraph.graph.graph_model Coq.Lists.List Coq.Lists.ListDec