P :=
8 9
   0    1    0    0    0    0    0    0    0
   0    0    1    0    0    0    0    0    0
   0    0    0    1    0    0    0    0    0
   0    0    0    0    1    0    0    0    0
   0    0    0    0    0    1    0    0    0
   0    0    0    0    0    0    1    0    0
   0    0    0    0    0    0    0    1    0
   0    0    0    0    0    0    0    0    1
;
assert((card P) = { });
