Neighbours
Place digits 1-3 in the grid so that in each row and column each digit appears three times. (Twice in the example.) Numbers in grey cells do not share an edge with a cell containing the same number. Numbers in white cells share an edge with at least one cell containing the same number.
Example:
Puzzle:
Solution code: Row 4, followed by column 4.
on 15. May 2022, 11:14 by Nick Smirnov
Penpa:
https://tinyurl.com/y6n687vd
on 14. February 2014, 18:45 by Richard
"h" added in the title
on 14. February 2014, 13:04 by Joo M.Y
Typo in title. (No "h" again!)
Please note: The German version of this page has changed. It is possible that this page does not contain the latest information.