3,5,9,,,4,2,8,
,7,,,2,9,3,5,4
,1,,,8,,7,,6
7,,1,,,8,,,
,,2,,,,8,,
,,,9,,,4,,7
1,,6,,9,,,4,
9,3,5,8,4,,,7,
,4,7,2,,,1,3,9