
0 0 5  3 0 0  0 0 0
8 0 0  0 0 0  0 2 0
0 7 0  0 1 0  5 0 0

4 0 0  0 0 5  3 0 0
0 1 0  0 7 0  0 0 6
0 0 3  2 0 0  0 8 0

0 6 0  5 0 0  0 0 9
0 0 4  0 0 0  0 3 0
0 0 0  0 0 9  7 0 0

Arto Inkala unsolvable: 4th hardest...
hardest according to some.
I have not solved this without guessing!
some xCycles...but KeyCell fails to solve
...guessed 1@78: then solved using multiple KeyCells;
Guessing 7@43 leads to contradiction so
choose 6, then KeyCells solves.
