unfold G2_5, G2.
eapply comp_spec_eq_impl_eq.
comp_skip.
eapply (@oc_comp_spec_eq _ _ _ _ _ _ _ _ _ _ _ _ _ _ (fun a b => forall z, arrayLookup _ a z = arrayLookup _ b z)).
intuition.
intuition.
eapply randomFunc_mem_spec.
intuition.
simpl in *.
intuition.
subst.
comp_simp.
simpl.
eapply comp_spec_eq_refl.
Qed.

Theorem G1_G2_equiv :
| Pr[G1] - Pr[G2] | <= Adv_WCR _ _ F (Rnd k) au_F_A.