% nurikabe 180 by ooya, http://www.janko.at/Raetsel/Nurikabe/180.a.htm
nurikabe
medium-
18 10
.4..........4.....
.....4............
.......1.4.......5
..................
....1...k....3.4..
..2.......4.......
.......2..........
..........2....5.3
....3.......1.....
..3........5..5...
