 m s d _ 2   m s d _ 3   m s d _ 3   m s d _ 3 
 0   0 
 0   0   0   0   - >   0 
 1   0   0   1   - >   1 
 1   0 
 0   1   2   2   - >   2 
 2   0 
 0   2   0   2   - >   3 
 3   1 
