Fill every outlined region with different numbers from 1 to N, where N is the number of cells in the region. No two adjacent cells can contain the same number. No two cells from different regions sharing a side can both contain the largest number of their corresponding regions.
(Rules and example from WPC 2017 IB, grey colouring of largest numbers are just for illustrative purposes)
History of the puzzle
Invented by Anurag Sahay (India) in 2017 as a submission for Puzzle Innovations Contest, a pre-event of WPC 2017.
Appearances in the past WPCs
- WPC 2017/Round 18 by Swaroop Guggilam