turing 135.0 106.0 252.0 120.0 419.0 132.0 121.0 247.0 271.0 259.0 0 1 0 R 3 3 0 0 L 0 0 a a L 2 2 b b L 3 3 1 1 L 1 3 L 2 1 0 1 R 1 2 a b L 3 3 b L 1 1 b b R 1 1 1 1 R 1 1 0 0 R 3 4 R 2 1 1 R 2 2 1 0 L