     #nodes  #regions   #procs   #which case
      28        5        3       MultipleRegionsPerProc
     nodeID   regionID   procID
       0         0         0
       1         0         0
       2         0         0
       3         0         0
       3         1         0
       4         1         0
       5         1         0
       6         1         0
       7         1         0
       8         1         0
       9         1         0
       9         2         1
      10         2         1
      11         2         1
      12         2         1
      13         2         1
      14         2         1
      15         2         1
      16         2         1
      17         2         1
      18         2         1
      18         3         2
      19         3         2
      20         3         2
      21         3         2
      22         3         2
      23         3         2
      24         3         2
      24         4         2
      25         4         2
      26         4         2
      27         4         2