*-----------*
|3.7|..1|6..|
|..6|4..|.97|
|.5.|...|21.|
|---+---+---|
|...|36.|..9|
|27.|...|.86|
|6..|.74|...|
|---+---+---|
|.61|...|.4.|
|59.|..7|8..|
|..8|6..|7.1|
*-----------*