  0   0   6  -1
  0   0  20   0
  0 -49  48  49
 -1   0   0  23
 26  35  41  29
 13  -2  15  14
 -2  16  13   9
 17  -3  10   0
  0   0   3  14
  9  18   0   0
 19  -3  11   0
  0   0   3
