proposition: Lemma eq_as_set_app: forall A (L1 L2 L3 L4: list A), L1 ~= L2 -> L3 ~= L4 -> (L1 ++ L3) ~= (L2 ++ L4).
proof: Proof. intros; hnf in *; intuition. Qed.
imports: Coq.Lists.List Coq.micromega.Lia Coq.Sorting.Permutation Coq.ZArith.ZArith_base Coq.ZArith.Zcomplements Coq.Logic.FunctionalExtensionality CertiGraph.lib.Coqlib CertiGraph.lib.EquivDec_ext VST.zlist.sublist VST.zlist.list_solver