Draw vertical/horizontal lines along the dashed lines to divide the grid into regions. A region may contain at most one number, equal to the area of the region. No region may cover a 2×2 area. Some dots are “heavy” and have 3 or 4 lines connected to them. Black dots indicate heavy dots with exactly three lines; white dots indicate heavy dots with exactly four lines. Not all heavy dots are given, but there can be no heavy dots one cell-edge away from the indicated ones.
(Rules and example from WPC 2017 IB)
History of the puzzle
Invented by Prasanna Seshadri (India). The first puzzle appeared on The Art of Puzzles blog in May 2014.
Appearances in the past WPCs
- WPC 2017/Round 2 by Prasanna Seshadri