induction ls2; intuition; simpl in *; subst.
destruct ls3; simpl in *; trivial. omega.
simpl in *.
eapply IHls2.
eauto.
omega.
Qed.

(* Specifications: *)
Lemma evalDet_steps_repeat_done_inv_h : forall (A : Set)(x y : comp_state A),
evalDet_steps x y ->
forall (P : A -> bool)(c : Comp A) s a s',
evalDet_steps x (cs_more (Repeat c P) s) ->
y = (cs_done a s') ->
evalDet_repeat_steps P (cs_more c s) (cs_done a s').