turing 87.0 133.0 324.0 131.0 181.0 323.0 395.0 318.0 0 2 L 1 0 a b R 2 2 a a L 2 2 b b L 1 2 L 0 1 a a R 1 0 b b R 2 3 R 0 0 b b R