↻ Whispering Loop ↺
(Published on 25. August 2023, 18:36 by ElChiglia)
---- RULES ----
Normal Sudoku rules apply: Fill the grid with digits 1 to 9 appearing once each in every row, column, and 3x3 box.
Shading: Shade some cells in the grid such that in each row, column, and 3x3 box exactly 2 cells are shaded. Shaded cells cannot touch each other, not even diagonally.
Whispering Loop: Draw a 1-cell-wide loop (orthogonally connected cells) through the unshaded cells, such that each 3x3 box is visited at least once. The loop cannot touch itself orthogonally but may touch diagonally. Digits in adjacent cells along the loop must differ by at least 5. Thus, the loop is a German Whispers line.
Outside clues: The clues given outside of the grid are Sandwich Sum clues. Digits between the 1 and 9 in the respective column or row sum to the given value. Additionally, all single digit clues outside of the grid fulfill two further roles:
- they indicate how many unshaded cells are in between the two shaded cells of that respective column or row.
- they give the total number of loop cells in that respective column or row.
---- LINKS ----
Solve this puzzle in the CtC app
Solve this puzzle on f-puzzles.com
This is the first sudoku in my series of “Build-your-own-loop Sudokus". If you liked solving this puzzle or if you prefer other combinations of loop logic and constraints, feel free to give the other sudokus of the series a go too:
| Loop Logic | Loop Constraint | Further Constraints | ||
|---|---|---|---|---|
| Road Running Loop |
Road Runner | Parity Line | Kropki Dots | |
| Magically Modifying Loop |
- | Incrementers, Decrementers, Nullifiers |
Magic Squares, Killer cages, Kropki Dots |
|
| Skiing Loop | Gates | German Whispers | Kropki Dot, Between Lines |
|
| Behaving Loop | 3x3 boxes | Polarity Line | Kropki Dots | |
| Magical Loop | Guiding cells | Modular Line | Magic Squares | |
| Foggy Loop | Guiding cells | Parity Line | Fog of War, Killer Cages |
|
| 10-Suȵ Loop | Moon-or-Sun | 10-Line | Killer Cages | |
| Counting Loop | Galaxies | Counting Line | Killer Cages, Kropki Dots, Quadruple Clues |
|
| Shining Loop | Moon-or-Sun | Parity Line | Killer Cages | |
| Interfering Loops | Slitherlink + Masyu |
Entropic Line + Parity Line |
Killer Cages | |
| Slithering Loop | Slitherlink | Entropic Line | Killer Cages, Little Killer |
|
| BigBang Loop | Galaxies | Parity Line | Row/Column Indexer, Kropki Dots |
|
| Summing Loop | Star Battle | Region Sum Line | Killer Cages, Skyscraper, Kropki Dots |
|
| Whispering Loop | Star Battle | German Whispers | Sandwich Sum |
Solution code: Row 8, followed by Column 8
Comments
on 19. May 2024, 04:21 by virus_dave
Oh wow, I found this one surprisingly difficult, but it's been awhile since I've done this kind of shading puzzle, so I kept messing it up and having to start over.
Once I stopped messing that up, the rest followed relatively straightforwardly.
Very nice puzzle!
on 11. November 2023, 01:43 by Mitsunari
It took me 62 minutes to solve but this combination of 2 puzzles was very funny to solve. It is quite smooth to solve once the logic is understood :) Good job, it was very fun!
on 12. October 2023, 10:25 by ElChiglia
@yttrio: thanks a lot for giving it a second go and for the nice feedback.
Thanks in general for all the positive feedbacks and ratings, a screenshot of the 100% will be framed to remember this moment :)
on 9. October 2023, 16:32 by yttrio
I broke the puzzle early on my first attempt, but I'm very glad I went back for a second try. Excellent, fun puzzle!
on 3. September 2023, 18:45 by ArnulfKoch
Very nice puzzle, i loved it.
on 26. August 2023, 22:39 by Baklin
It took me 2 hours but got there in the end. Just like Big Tiger said, it feels like I missed some trick to finish it smarter.
------
First of all, thanks for still finishing it even though it took you two hours. I must admit, I think this indeed means that you might have missed some 'trick' unfortunately. I will post a hidden comment with some remarks about my intended approach, to not spoil the fun for other solvers. Well, at least I hope there will be others still attempting it who are not discouraged by the apparent potential of missing the intended solve path :)
-- ElChiglia
on 26. August 2023, 21:05 by Cheetos
Great puzzle, I enjoyed a lot solving it. Like Evicts wrote, it seems challenging at the first glance but it’s solvable in a nice flow. The interaction of the sandwich sums and the whisper line was a nice way to start the sudoku part of the puzzle.
on 26. August 2023, 09:31 by Big Tiger
Goodness, that was not "very approachable" to my mind - I'm wondering if I missed a "clever deduction" of some kind. But I did make it!
on 26. August 2023, 08:56 by ElChiglia
Rephrased the rules regarding single digit outside clues
on 26. August 2023, 07:57 by Big Tiger
"All single-digit clues" - does that include the 1 and the 5? Or JUST the outside clues?
-------
This does not include the given digits, only the outside clues are meant. I will try to phrase it more obvious in the rules.
on 26. August 2023, 00:06 by Evicts
Looked quite daunting at first glance but ended up being very approachable. I enjoyed solving it.
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Thanks a lot for giving it a go even though it looked daunting. I am happy that you enjoyed it and thanks for your positive feedback.
-- ElChiglia
