Half Circles
(Published on 10. September 2025, 20:51 by Prof.Dori)
Half Circles
Rules:
Normal sudoku rules apply.
A digit N placed inside a circle or semicircle indicates that exactly N full circles in the grid contain the digit N.
Two semicircles together count as one full circle. For example, if there are four semicircles containing the digit 5 and three full circles containing the digit 5, then the total count is 2+3=5 circles with the digit 5.
Solution code: Row 1.
Comments
on 26. October 2025, 21:14 by VitP
very nice, that's a fact, but hardly level 1.
FIRST, you really do need a lot of experience with counting circles.
NEXT, you have to recognize that most of that DOES NOT APPLY, so you have to create entirely new procedures.
THEN you need to be comfortable with basic algebra.
ONLY THEN is the puzzle easy.
on 17. October 2025, 21:59 by MandaKakes
Really love this rule concept. It's so fun to work with. Great job!
on 2. October 2025, 20:51 by morgannamodeaura
one of the coolest 0 star / GAS-type puzzles i've ever solved here!
on 29. September 2025, 15:41 by Nebuzaradan
This is a model for what an introductory puzzle to a new rule type should be.
on 16. September 2025, 17:06 by mightcould
Very nice and smooth setup!
on 15. September 2025, 18:25 by fthompson
Amazing puzzle!
I know it's not relevant to the solve, but the "Two semicircles together count as one full circle" rule seems slightly ambiguous to me. What happens if the digit appears in an odd number of semicircles?
For example, if you had a 1 in three different semicircles and no full circles would it count as being in 1.5 full circles or 1 full circle? Just wondering in case this ruleset is used for harder puzzles in the future!
on 15. September 2025, 05:46 by CalvinM
Absolutely brilliant puzzle! I'm amazed how cleanly it solved, it felt very much like the path was a carpet being unfurled in front of me. Thank you for creating this!
on 13. September 2025, 16:41 by xiaoji
easy yet nicely settled!
on 11. September 2025, 21:15 by SanFranSam
I don't know if i solved it as much as i intuited it. ;)
on 11. September 2025, 14:52 by SirMoose
I really liked the addition of semi circles in this ruleset, definitely 1 star, but I would absolutely love to see what this constraint could offer in tougher puzzles!
on 11. September 2025, 12:47 by Franjo
Funny puzzle! Thank you very much for creating and sharing.
on 11. September 2025, 11:13 by marty_sears
Really brilliant twist on counting circles, and nice aesthetics too :)
on 11. September 2025, 11:02 by Ol-Jay
This was really awesome and brilliant, I loved the flow!
on 11. September 2025, 07:30 by Karitsu
This was fascinating. I really want someone to do a proof video on why it works the way it does.
on 11. September 2025, 02:50 by josemadre
So great!
on 11. September 2025, 02:47 by marajade
Beautiful! I loved how this unfolded.
on 11. September 2025, 00:01 by NorthCoastAsher
Very simple puzzle, but a great constraint!
on 10. September 2025, 22:40 by Qodec
Too good to be true. Someone please wake me up?
on 10. September 2025, 21:22 by mathpesto
Brilliant!
