Empty Circles
(Published on 20. October 2023, 17:32 by Qodec)
Heavily inspired by a recent glum_hippo puzzle called 'Chillicothe'.
- Sudoku: Each row, column, and region indicated by thick borders in the grid must contain the digits 1 to 9 once each.
- Odd/Even: Cells with an opaque grey circle contain an odd digit. Cells with an opaque grey square contain an even digit.
- Circle Counters: A digit in a cell with an outlined circle indicates exactly how many outlined circles contain that digit.
N.B. r1c1 and r6c3 are odd and contain an outlined circle; r5c8 and r8c5 are even and contain an outlined circle; all other cells contain at most one clue.
You can play this puzzle online using:
- CTC app: http://tinyurl.com/hz623h6s
- f-puzzles: https://f-puzzles.com/?id=yv95asgo
Good luck!
Solution code: Row 4 and column 4. I.e. the 9 digits in row 4 from left to right, followed by the 9 digits in column 4 from top to bottom, for example: 123456789123456789
Comments
on 21. February 2024, 20:40 by Playmaker6174
It's shocking how the one breaking symmetry clue in R6C3 could produce so much fruitful (and tight) deductions throughout, and I like how every odd/even clue played some vital roles in the mid solve! Thanks for this cool puzzle :)
on 7. December 2023, 13:21 by Vebby
Very cool logic!
on 3. December 2023, 00:00 by Fool on Hill
This was such a good puzzle to solve. Sometimes, when I solve a puzzle, I know I have not quite got the point - the deductions I have made are fine, but there is a hint of something else going on that I have missed. I solved this three times just because I wanted to appreciate it fully. Qodec, that is a regular experience with your puzzles - somehow you are always setting at the limit of what I can understand - and I love the challenge. Thanks so much for this beauty.
on 4. November 2023, 18:58 by anyeyeball
Very nice. Loved how the outlined circles came together from all the other clues. Thanks!
on 1. November 2023, 21:56 by Niverio
Mind bending puzzle! Such a unique solve path.
on 24. October 2023, 15:01 by jinkela114514
The rating suddenly dropped to 93% after refreshing
on 22. October 2023, 12:22 by econtrout
The initial solution path was quite elegant. I found the intermediate stages quite up hill. I think I missed something there. Overall a great puzzle. Thanks!
on 21. October 2023, 15:34 by yuanbangod
good
on 20. October 2023, 19:05 by Ood
Very nice
on 20. October 2023, 17:36 by glum_hippo
First past the post! What an enjoyable puzzle, if slightly maddening... but I recommend everyone try this. The ideas are a very nice contrast to those in 'Chillicothe'
