% nurikabe 230 by ooya, http://www.janko.at/Raetsel/Nurikabe/230.a.htm
nurikabe
medium-
18 10
2....7...b........
......4...7.......
..................
.1........8....2..
..................
....3.......3.....
7...............4.
.8................
.............1.3.1
..c...............
