*-----------*
|.8.|6..|...|
|..1|3.4|2..|
|4..|...|675|
|---+---+---|
|...|5..|..4|
|..7|843|5..|
|1..|..6|...|
|---+---+---|
|972|...|..3|
|..6|1.5|9..|
|...|..9|.8.|
*-----------*