proposition: Lemma addr_min_max x y : min x y + max x y = x + y.
proof: Proof. by rewrite /min /max; case: ifP => //; rewrite addrC. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(ssrAC div fintype path bigop order finset fingroup) mathcomp(ssralg poly)