% slitherlink 440 by Otto Janko, http://www.janko.at/Raetsel/Slitherlink/440.a.htm
slitherlink
very hard
30 20
33.21...22.23.2.2.2..2.2.2...3
....23.3.11...1..2112.2212.1..
..1...1...3..212.13...122..2.2
....2233.2..2..2.2.1.322..1233
22......1....121.2.213..3.1.22
31.2.3...3.213..2..2.....223..
3...211.21....121.212..3.....3
.2...3.21....3...2.....1.3..2.
3..2..3122.313.12322...23.1..2
.232.12.3.23.3.3.22......3..2.
........32...2.2...22.2..3.222
31.231..213...20...2.3.22.322.
.2...2.3.3..022..2..2.12......
.11....3......1..1...3..3....2
...........2...3.2232....213.3
21232.3..0.1212.2.1.2..2..2...
.12213.13.32....122.3.32....3.
.233.2.3...23.......13.0.22.2.
....12..2.322.....1...1.....22
3.33.........31.3.3..3..23.2..
