proposition: Lemma remove_not_in {A: Type} (eq_dec : forall x y : A, {x = y} + {x <> y}): forall l x, ~ In x l -> remove eq_dec x l = l.
proof: Proof. induction l; intros; simpl; auto. destruct (eq_dec x a). subst. exfalso; apply H, in_eq. f_equal. apply IHl. intro; apply H. apply in_cons. auto. 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