*-----------*
|...|...|...|
|6.8|1..|7..|
|...|.74|.9.|
|---+---+---|
|1..|59.|36.|
|..7|.8.|5..|
|.34|.61|..7|
|---+---+---|
|.2.|34.|...|
|..3|..6|8.5|
|...|...|...|
*-----------*