% nurikabe 424 by Otto Janko, http://www.janko.at/Raetsel/Nurikabe/424.a.htm
nurikabe
medium-
12 12
......4....3
............
..4...2.1..4
.4..........
.........4..
3.2..2......
....3....1..
..1...3...3.
............
.2.........2
......1.....
3...2.....6.
