proposition: Lemma mypath_ok a p : uniq (a :: p) -> path myrel a p -> (a :: p) \in mypath (m+n).
proof: Proof. move /card_uniqP => Hsz Hp. have Hc: #|a::p| <= #|id'| by apply max_card. rewrite Hsz card_sum !card_ord in Hc. by apply mypath_ok_rec. Qed.
imports: Wf_nat Init.Wf Recdef Reals mathcomp(all_ssreflect perm zmodp matrix ssralg) mathcomp(Rstruct) ssrR Reals_ext ssr_ext ssralg_ext bigop_ext f2 fdist channel pproba linearcode subgraph_partition tanner tanner_partition summary ldpc checksum ldpc_algo