% nurikabe 13 by Warai Kamosika, http://www.janko.at/Raetsel/Nurikabe/013.a.htm
nurikabe
medium-
18 10
.....a............
...1..............
.2..7.............
3.................
...5....2.........
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..2...............
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...1...5...9...6..
..3...4...5...d..2
