[0] 0: 1 6 11 16
[1] 0: 21 26 6 7
[2] 0: 8 9 10 11
[0] 0: 0 1 1 6 0 1 2 3
[1] 0: 0 1 0 1 2 3 2 3
[2] 0: 8 9 10 11 6 7 6 7