*-----------*
|.28|...|...|
|.6.|2..|.51|
|1..|.6.|.28|
|---+---+---|
|...|51.|4..|
|..7|6.3|2..|
|..1|.29|...|
|---+---+---|
|28.|.9.|..7|
|71.|..2|.6.|
|...|...|84.|
*-----------*