Logic Masters Deutschland e.V.

Yajilin Sandwich Sudoku

(Published on 6. October 2026, 14:43 by phil_the)

This puzzle was my entry for the second week of Scojo's imposter challenge. I was supposed to make a puzzle imitating the style of Piatato which was a huge ask. I never expected to fool anyone with this puzzle. You can see Piatato's own puzzle here. I suspected he might make a U-Bahn but knew that there was no way I could learn to set that type of puzzle within a week. So I went for Yajilin instead. Even so, I was completely new to Yajilin, so this was still a challenge. The turning corners on odd digits idea came from an old Madmahogany puzzle which I found featured at CtC. I noticed that Piatato had made a few puzzle inspired by rule combinations that other setters had used, so I thought this was a valid approach. Madmahogany's puzzle used a lot of given sudoku digits. For mine I decided to use sandwich sums instead but I still ended up needing a few givens to make it work.


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Sudoku: Every row, column, and box must contain the digits 1-9 with no repeats.

Yajilin: Digits in cells with arrows give the number of shaded cells in the given direction. Cells with arrow clues or given digits are not shaded. Shaded cells cannot touch orthogonally. The remainder of the grid (excluding shaded cells, cells with arrows or given digits) must be a part of a single continuous non-intersecting loop. Also, the loop can only turn in a cell containing an odd digit.

Sandwich sums: Numbers outside the grid give the sum of digits between the 1 and 9 in that row or column.

Solution code: unshaded cells in row 9

Last changed on on 7. October 2026, 11:34

Solved by efnenu, Piatato, Calvinball, Franjo, Joyofrandomness, Ambrose, gdc, emoney1374, MaizeGator, Jesper, SeveNateNine, tempsperdu, MagnusJosefsson, zuzanina, SudokuHero, ManlyPebbles, Andrewmi3, ... SFP, SweJo, eriomon, Christounet, OJPS, mathpesto, nocturnomath, Myreque, dawsonjones2020, sedici, shifman23, Tank, Calesch, marcmees, Lizzy01, NEWS, Tompzini, Vodakhan , kangaroo, ManuH, fwd99
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Comments

on 7. October 2026, 14:06 by Christounet
Very fun puzzle! Thanks :)

Last changed on 7. October 2026, 11:42

on 7. October 2026, 11:34 by phil_the
Apologies. Clues are not considered shaded and are not on the loop.
I believe that is standard for Yajilin but I should have made that clear.

on 7. October 2026, 02:36 by RockyRoer
Are arrow cells shaded? Are the given digits shaded? I don't understand how they can be touching in box 6?

on 6. October 2026, 17:54 by Piatato
Really smooth and fun puzzle, I had a great time solving it!

on 6. October 2026, 17:44 by MaizeGator
Very unique ruleset. I did not expect this combination of rules to work as well as it did. I especially liked the resolution.

on 6. October 2026, 17:27 by emoney1374
Great puzzle! Lots of fun

on 6. October 2026, 16:23 by Franjo
Thank you very much for creating and sharing this unusual hybrid.

Difficulty:3
Rating:95 %
Solved:48 times
Observed:4 times
ID:000THC

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Solution code:

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