universe@7: _ _ _ 1 9 _ _ _ 8
universe@7: 1 _ _ 2 _ 7 9 6 _
universe@7: 6 9 _ _ _ 4 _ _ _
universe@7: _ _ _ _ _ _ 1 _ _
universe@7: _ 5 _ 6 _ 9 _ 7 _
universe@7: _ _ 3 _ _ _ _ _ _
universe@7: _ _ _ 9 _ _ _ 8 1
universe@7: _ 1 6 7 _ 8 _ _ 3
universe@7: 9 _ _ _ 1 2 _ _ _