Hex Islands

Rules

Blacken some cells. White cells should form six islands which consist of six cells each. Islands cannot touch each other.

(Rules and example from WPC 2015 IB)

History of the puzzle

Invented by László Mérő (Hungary) in 1999 under the name "Honey Islands". First presented in a single-puzzle round of WPC 1999 (WPC 1999/Part 7).

Most Hex Islands puzzles can only be solved by guessing and tweaking; it is extremely hard to verify the uniqueness of Hex Islands puzzles by hand. It was so difficult that the aforementioned round contained multiple puzzles with multiple solutions.

Appearances in the past WPCs

• WPC 2015/Round 2 by Andrey Bogdanov
• WPC 1999/Part 7 by László Mérő