*-----------*
|3..|.6.|...|
|.6.|...|3.1|
|.4.|..1|.8.|
|---+---+---|
|1..|64.|2..|
|4.2|.1.|9.7|
|..6|.27|..4|
|---+---+---|
|.1.|5..|.4.|
|2.9|...|.5.|
|...|.8.|..3|
*-----------*