b a c a a a a a a x1 a a a a a a a b a c b a c x1 2.2 b a c a a a a a a x1 b a c x1 b a c a a a a a a x1 b a c b a c x1 true b a c a a a a a a x1 b a c b a c x1 b a c a a a a a a x1 b a c x1 true Failed! NaTT certifiable-1.6