*-----------*
|..4|5.6|...|
|87.|...|5..|
|..3|.7.|.62|
|---+---+---|
|3..|68.|...|
|4..|...|..6|
|...|.52|..8|
|---+---+---|
|68.|.4.|2..|
|..9|...|.35|
|...|2.9|1..|
*-----------*