Reading from left to right, top to bottom, every Nth shaded cell is marked by a dot. N is a constant value that needs to be determined by the solver. The shaded cells must form a single connected area, i.e. the wall. No 2×2 group of cells can be entirely shaded. The number at the top of the clue gives the number of shaded cells around it, and the number at the bottom gives the number of dots around it.
(Rules and example from WPC 2017 IB)
History of the puzzle
Appearances in the past WPCs
- WPC 2017/Round 22 by Swaroop Guggilam