
9 0 0  0 8 0  0 4 1
0 8 0  0 0 0  0 2 0
0 0 6  0 0 9  8 0 0

0 0 0  4 0 1  3 0 0
3 0 0  0 7 0  0 0 4
0 0 5  8 0 3  0 0 0

0 0 7  5 0 0  2 0 0
0 6 0  0 0 0  0 7 0
2 9 0  0 1 0  0 0 5

extreme #504 sudokuWiki 2jun23
needed several k-key to solve

