Section expected_poly_time_theory.
Context `{ept : expected_poly_time_predicate}.
intuition.
eapply (@expected_poly_time_compose _ _ _ _ _ _ (fun n a b => (f2 n b))); eauto.
eapply expected_poly_time_const; eauto.
Qed.
intuition.
eapply (@expected_poly_time_compose _ _ _ _ _ _ (fun n a b => f3 n (f1 n a) b)); eauto.
eapply (@expected_poly_time_compose _ _ _ _ _ _ (fun n a b => f3 n b)); eauto.
eapply expected_poly_time_const.
eauto.
Qed.
intuition.
eapply (@expected_poly_time_compose_binary _ _ _ _ _ _ (fun n b c => pair b c)); eauto.
eapply expected_poly_time_pair.
Qed.
intuition.
eapply (@expected_poly_time_compose_binary _ _ _ _ _ _ BVxor); eauto.
eapply expected_poly_time_bvxor.
Qed.
intuition.
eapply (@expected_poly_time_compose_binary _ _ _ _ _ _ (fun n a b => eqb a b)); eauto.
eapply expected_poly_time_eqb_bool.
Qed.
intuition.
eapply (@expected_poly_time_compose_simp _ _ _ _ (fun n a => fst a)); eauto.
eapply expected_poly_time_fst.
Qed.

Theorem expected_poly_time_snd_f :
forall (A B C : nat -> Type)(f : forall n, A n -> (B n * C n)),
efficient _ f ->
efficient _ (fun n (a : A n) => snd (f n a)).