#[local]
Hint Resolve remove_min_gt_tree : core.

(* Specifications: *)
Lemma remove_min_find : forall l x e r h y,
bst (Node l x e r h) ->
find y (Node l x e r h) =
match X.compare y (remove_min l x e r)#2#1 with
| LT _ => None
| EQ _ => Some (remove_min l x e r)#2#2
| GT _ => find y (remove_min l x e r)#1
end.