proposition: Lemma mapsto_2levels c cl ll lx lv lr x v cr rl rx rv rr y e : (Node c (Node cl ll lx lv lr) x v (Node cr rl rx rv rr))@y ↦ e <-> (Node cl ll lx lv Leaf)@y ↦ e \/ (Node c lr x v rl)@y ↦ e \/ (Node cr Leaf rx rv rr)@y ↦ e.
proof: Proof. rewrite !node_mapsto, !leaf_mapsto. rtauto. Qed.
imports: Coq(Bool BinPos Pnat Setoid SetoidList PeanoNat) Coq(Orders OrdersFacts OrdersLists) MMaps(Utils Interface OrdList GenTree)