1) Logic puzzle 
Heyawake (Japanese: へやわけ, `divided rooms`) is a binary-determination logic puzzle published by Nikoli. As of 2013, five books consisting entirely of Heyawake puzzles have been published by Nikoli. It first appeared in Puzzle Communication Nikoli #39 (September 1992). ==Rules== Heyawake is played on a rectangular grid of cells with no sta.....