*-----------*
|..6|9..|...|
|4..|...|9..|
|.1.|.63|5..|
|---+---+---|
|8.5|.3.|4..|
|.2.|8.4|.5.|
|..1|.9.|2.6|
|---+---+---|
|..7|65.|.2.|
|..4|...|..5|
|...|..9|8..|
*-----------*