*-----------*
|78.|1.9|...|
|.1.|...|.4.|
|...|65.|...|
|---+---+---|
|.2.|..6|5..|
|567|...|819|
|..1|8..|.2.|
|---+---+---|
|...|.62|...|
|.4.|...|.6.|
|...|3.8|.71|
*-----------*