proposition: Lemma step_edom_edom p : p != start_port -> p \in step_edom -> p \in edom c.
proof: Proof. by rewrite step_edom_ok 2!inE => /negbTE ->. Qed.
imports: mathcomp(all_ssreflect ssralg fingroup zmodp poly ssrnum) mathcomp(matrix perm) ssr_ext ssralg_ext fdist subgraph_partition tanner