% slitherlink 637 by Luke Pebody, http://www.janko.at/Raetsel/Slitherlink/637.a.htm
slitherlink
medium
19 16
....33..2..23..33..
.....1.3....1.12..2
11..2..0....2.2.12.
.33331322202223....
.1.....1.....02232.
.3..22.3...223....2
321..2.....2..03..2
232..2.3.....33..2.
220.2..03.....223..
..3....3.22.21.....
.2202.11..2.21.2...
223.3..2.1..2.203..
222..2.2.1.23222...
32.12.202.......202
22..3...22...21..3.
...22.2.......1.2..
