0 --> 1: 1 0 --> 2: 2 1 --> 0: 2 1 --> 3: 1 2 --> 2: 1 3 --> 1: 1 0 --- 1: 1 0 --- 2: 2 1 --- 3: 1 2 --- 2: 1 0 --- 1: 2 2 --- 2: 1 1 --- 3: 1 0 --- 1: 1 1 --- 3: 1 2 --- 2: 1 0 --- 1: 2 0 --- 2: 2 1 --- 3: 1 2 --- 2: 1 0 --- 1: 3 0 --- 2: 2 1 --- 3: 2 2 --- 2: 1
