*-----------* |.8.|6..|...| |..1|3.4|2..| |4..|...|675| |---+---+---| |...|5..|..4| |..7|843|5..| |1..|..6|...| |---+---+---| |972|...|..3| |..6|1.5|9..| |...|..9|.8.| *-----------*