% heyawake 6 by ?, http://www.janko.at/Raetsel/Heyawake/006.a.htm
heyawake
medium-
10 10
+-----+-----+---+---+
|2....|3....|2..|2..|
|.....|.....|...|...|
|.....|.....|...|...|
|.....+-----+...|...|
|.....|.....|...|...|
+-----+-----+-+-+-+-+
|.....|7......|...|.|
+-+---+.......|...|.|
|.|...|.......|...|.|
|.|...|.......|...|.|
|.|...|.......|...|.|
|.|...|.......+---+-+
|.|...|.......|2....|
+-+-+-+-+-----+-----+
|...|...|.....|3....|
|...|...+-----+.....|
|...|...|2....|.....|
|...|...|.....|.....|
|...|...|.....|.....|
+---+---+-----+-----+
