proposition: Lemma lerP x y : ler_xor_gt x y (min y x) (min x y) (max y x) (max x y) `|x - y| `|y - x| (x <= y) (y < x).
proof: Proof. exact: real_leP. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(ssrAC div fintype path bigop order finset fingroup) mathcomp(ssralg poly)