*-----------*
|3..|.9.|65.|
|...|2..|.7.|
|.6.|...|..8|
|---+---+---|
|..6|5..|31.|
|1..|...|..2|
|.29|..1|8..|
|---+---+---|
|5..|...|.8.|
|.3.|..6|...|
|.97|.4.|..1|
*-----------*