f f x f c f x f f x f d f x g c x x g d x x g c h 0 g d 1 g c 1 g d h 0 g h x g x 2.2 g c 1 g d h 0 f f x f c f x g h x g x f f x f d f x g c h 0 g d 1 true f f x f d f x false g h x g x true h 1 1 1 1 0 0 d 1 0 c 1 0 f 1 0 0 0 0 f 1 0 g 1 1 0 g 1 0 g c h 0 g d 1 false f f x f c f x false g c 1 g d h 0 false NaTT certifiable-1.6