proposition: Lemma connected_component_sym A x y : connected_component A x y -> connected_component A y x.
proof: Proof. by move=> [B [*]]; exists B. Qed.
imports: HB(structures) mathcomp(all_ssreflect all_algebra finmap generic_quotient) mathcomp(boolp classical_sets functions) mathcomp(cardinality mathcomp_extra fsbigop) reals signed