Circumdifference
(Published on 23. July 2026, 08:00 by Kaktuslav)
Rules: Normal sudoku rules apply. Circles and dots: Place nine circles in the grid: one in each row, column, and 3×3 box, with the circled cells forming a complete set of the digits 1–9. Digits separated by a dot differ by the circled digit in their shared row or column. For example, if the circled digit in a column is 3, digits separated by any dot in that column differ by 3. Not all possible dots are necessarily given.
Solution code: Row 1
Comments
yesterday, 19:16 by kasperd
What an original idea.
yesterday, 03:43 by henryng
Shockingly approachable, though not at all easy! Was amazed to see the kinds of deductions you could make even before determining a single digit
on 31. July 2026, 01:05 by jaredbitz
Very interesting concept, approachable once you think through it. Thank you very much!
on 30. July 2026, 20:56 by meatbox
what a fascinating puzzle ❤️
on 30. July 2026, 19:49 by jez9999
Took me quite a while to really get the implications of the logic and know where to look.
on 29. July 2026, 12:15 by Kattorzeh
I was surprised to see how this sudoku could work.
on 28. July 2026, 17:55 by PancakePie
Very fun and well built! Thank you.
on 28. July 2026, 17:54 by Flinty
Very nice! :)
on 27. July 2026, 12:47 by Klausku
Wonderful puzzle. And not too difficult. I enjoyed it a lot. Thanks!
on 26. July 2026, 03:08 by Crusader175
Cool idea!
on 24. July 2026, 22:11 by amchap
That felt intimidating going in, but flowed really nicely. Thanks.
on 24. July 2026, 00:22 by Snaques
Amazing puzzle. Really cool to get the hand of the rule and see the puzzle unravel. Very rewarding in the end.
on 23. July 2026, 19:45 by Lulero
I love puzzles like this. They make you think about their rules and discover new things, without being too hard either. A real treat, keep them coming. Thank you!
on 23. July 2026, 19:27 by sujoyku
What an awesome puzzle! Thank you, Kaktuslav!
on 23. July 2026, 19:24 by Franjo
Thank you very much for creating and sharing another amazing puzzle. Fantastic new constraint!
on 23. July 2026, 16:00 by pmays123
Brilliant. Incredibly fun. Thank you for sharing
on 23. July 2026, 15:50 by galium_odoratum
2.5* for me. Brilliant puzzle, very fun and unique!
on 23. July 2026, 14:05 by TeddieMilo
Very nice puzzle, love it! Thank you!
on 23. July 2026, 13:56 by vukkarak
Nice logic, enjoyable solve!
on 23. July 2026, 13:32 by HumanBirdsong
That was beautiful! Such an enjoyable experience once the logic 'clicked'. Thank you for setting :)
on 23. July 2026, 13:25 by Major314
Great break-in and smooth flow afterwards !
on 23. July 2026, 13:10 by amirs
Lovely and quite approachable.
on 23. July 2026, 13:05 by Dag H
Very clever setting, well done.
on 23. July 2026, 12:04 by eladv
That was absolutely gorgeous! Really fun logic, lots of stuff to spot, I didn't get stuck anywhere, but it was not "obvious" where to look, and there was a bit of cool bonus logic to do mid-solve. Thank you Kaktuslav!
on 23. July 2026, 09:30 by wuc
Refreshing ruleset new to me. Great logic. 2.5* from my solve time. Fun every second. Brilliant setting thx.
