msd_s2 msd_s2

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

1 0
0 0 -> 0
0 1 -> 2

2 0
0 0 -> 4
1 1 -> 4

3 0
0 0 -> 4

4 1
