proposition: Lemma oarcxx_le e x u : oarc G e x u x -> 1∥le G e ≡ 1∥u.
proof: Proof. case => E [[|] [A B /= C]]; by rewrite C ?par_tst_cnv. Qed.
imports: HB(structures) Coq(Relation_Definitions Morphisms RelationClasses) mathcomp(all_ssreflect) GraphTheory(edone finite_quotient preliminaries bij equiv) GraphTheory(setoid_bigop structures pttdom rewriting) GraphTheory(finmap_plus)