ref: 1984f6813cc216e3c98e402ce3f381a531faf1b1
dir: /sys/games/lib/sudoku/boards/veasy000.su/
361.259.. .8.96..1. 4......57 ..8...471 ...6.3... 259...8.. 74......5 .2..18.6. ..547.329 361725948 587964213 492831657 638259471 174683592 259147836 746392185 923518764 815476329