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