proposition: Lemma eformat_symm: forall u v, eformat (u,v) = eformat (v,u).
proof: Proof. intros. destruct (Z.lt_trichotomy u v). rewrite eformat1. rewrite eformat2. simpl; auto. simpl; lia. simpl; lia. destruct H. rewrite eformat1. rewrite eformat2. simpl; auto. simpl; lia. simpl; lia. rewrite eformat2'. rewrite eformat1. simpl; auto. simpl; lia. simpl; lia. Qed.
imports: VST.floyd.proofauto CertiGraph.lib.EquivDec_ext CertiGraph.lib.List_ext CertiGraph.lib.find_lemmas CertiGraph.graph.graph_model CertiGraph.graph.graph_gen CertiGraph.graph.graph_relation CertiGraph.graph.undirected_graph CertiGraph.graph.MathAdjMatGraph