tower x f a x s 0 f a 0 y y f a s x y f b y s x f b y x f a half x exp y exp 0 s 0 exp s x double exp x double 0 0 double s x s s double x half 0 double 0 half s 0 half 0 half s s x s half x 2.2 exp s x exp x f a s x y f b y s x f b y x f a half x exp y f b y x exp y tower x f a x s 0 f b y x half x half s 0 half 0 half 0 double 0 exp s x double exp x double s x double x half s s x half x true tower x f a x s 0 false f b y x f a half x exp y f a s x y f b y s x true Failed! NaTT certifiable-1.6