*-----------*
|8.7|26.|...|
|..5|..1|..7|
|.29|75.|...|
|---+---+---|
|2..|..6|.4.|
|..6|...|7..|
|.5.|9..|..3|
|---+---+---|
|...|.23|15.|
|6..|5..|3..|
|...|.97|2.6|
*-----------*