8 _ _ | _ 2 1 | 5 _ _
_ _ 6 | 7 _ _ | _ _ _
2 9 5 | 4 _ _ | 7 1 _
-------|--------|--------
6 _ _ | 1 _ _ | 8 _ _
5 _ _ | _ 4 _ | _ _ 7
_ _ 2 | _ _ 7 | _ _ 9
-------|--------|--------
_ 5 8 | _ 1 _ | 2 6 4
_ 6 1 | 2 _ 4 | 3 _ _
_ 2 4 | 8 6 _ | _ _ 1

8 _ _ | _ 2 1 | 5 _ _
_ _ 6 | 7 _ _ | _ _ _
2 9 5 | 4 _ _ | 7 1 _
-------|--------|--------
6 _ _ | 1 _ _ | 8 _ _
5 _ _ | _ 4 _ | _ _ 7
_ _ 2 | _ _ 7 | _ _ 9
-------|--------|--------
_ 5 8 | _ 1 _ | 2 6 4
_ 6 1 | 2 7 4 | 3 _ _
_ 2 4 | 8 6 _ | _ 7 1