msd_fib{0, 1} {0, 1} 

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

1 1
0 0 1 -> 2

2 0
1 1 0 -> 3

3 1
0 0 1 -> 4

4 0
0 1 0 -> 3
