Logic Masters Deutschland e.V.

Japanese Sum Cave Cipher #3: Indexed Empty Cells

(Eingestellt am 20. Oktober 2022, 06:39 Uhr von KNT)

Let's see how long it takes until I run out of ideas for these :)


Place the digits 1 to 9 exactly once in each row and column of the grid, and some cells in the grid are to be shaded such that the final shading of the grid resembles a valid cave (All unshaded cells are orthogonally connected and all shaded cells are orthogonally connected by other shaded cells to an edge of the grid).

Outside clues are Japanese sum clues. "?" is a stand in for any digit 0-9, but for a double digit number, the first digit may not be 0. Each distinct letter represents some unique digit from 0 to 9.

Clues to the left of the grid are Japanese sum clues for either shaded or unshaded groups of cells, where each group needs at least one of the other (shaded or unshaded) to separate the groups. Clues to the top of the grid are Japanese sum clues for the OTHER of shaded or unshaded. (That is, if it turns out clues to the left indicate sums of unshaded blocks, clues to the top indicate sums of shaded blocks). All outside clues are given.


There is one cell in every row and column that is neither shaded nor unshaded, and does not contain a digit. Clues to the right and bottom of the grid index this special cell in their row or column (from the right or bottom respectively). Neither shaded nor unshaded cells may connect through these special cells. These cells also serve as delimiters for all Japanese sum clues.

Play on Penpa+!

Answer check is enabled with blue sudoku digits.

Below is an example on the digits 1-6. For the simplicity of a smaller puzzle, A-F are restricted to only the digits 1-6.

Example puzzle

Lösungscode: Row 5, then Column 4, with X for empty cells

Zuletzt geändert am 10. November 2022, 19:35 Uhr

Gelöst von polar, Koalagator2, Vebby, Jesper, ONeill, Playmaker6174, Niverio, cdwg2000, marcmees, Xendari, MagnusJosefsson, Alex, ibag, Agent, r45, AnnaTh, harrison, ascension, misko, Mark Sweep, ffricke, zwooz19, jkuo7, RJBlarmo, dunder, lerroyy, Myxo, Sewerin, Gliperal
Komplette Liste


am 10. Januar 2023, 00:29 Uhr von lerroyy
Great puzzle, thanks!

am 10. November 2022, 19:35 Uhr von KNT

Zuletzt geändert am 22. Oktober 2022, 22:09 Uhr

am 22. Oktober 2022, 17:21 Uhr von AnnaTh
Can't get enough of your fantastic puzzles. I hope you will not run out of ideas so soon.


this makes me really really happy, @AnnaTh. don't worry- I truly love setting and am lucky enough to have the free time to do it quite often, ideas are definitely still aplenty :)

am 21. Oktober 2022, 22:26 Uhr von ibag
Great fun!

am 21. Oktober 2022, 21:07 Uhr von KNT
Updated visuals: using "?" instead of "." for better visibility

Zuletzt geändert am 21. Oktober 2022, 11:11 Uhr

am 21. Oktober 2022, 11:09 Uhr von MagnusJosefsson
Great puzzle as always! It took me a while to get started on this one, then it became an exciting ride with a variety of cool logic.

Zuletzt geändert am 22. Oktober 2022, 05:34 Uhr

am 21. Oktober 2022, 04:23 Uhr von marcmees
you never disappoint (I suppose Niverio means). The opening was found quickly but the empty cell definitely complicated things hence forward. Nice. thanks.

Zuletzt geändert am 21. Oktober 2022, 11:30 Uhr

am 20. Oktober 2022, 21:34 Uhr von Niverio
Absolutely amazing. You never disappoint, and always come up with exciting things, KNT!

(Edited out "ceased to" from before disappoint because apparently I was having a brainfart while writing the comment... Thanks marc for pointing it out lol)

am 20. Oktober 2022, 19:33 Uhr von Playmaker6174
Another spectacular and beautiful puzzle as always! The opening actually drained my mind for a long while before I started to notice something, then after that it's a long and smooth flow with plenty of lovely deductions ;)

am 20. Oktober 2022, 13:51 Uhr von ONeill
This one flowed really nicely and I made a lot less mistakes than the other two. Hopefully that’s the same for the fourth!

am 20. Oktober 2022, 11:58 Uhr von Jesper
Great puzzle! The empty cells really turn a lot of things on its head. Looking forward to #4 :)

am 20. Oktober 2022, 10:12 Uhr von Vebby
Cool new twist, particularly enjoyed the connectivity logic in this one. I'm all for a #4 too! ;)

am 20. Oktober 2022, 06:50 Uhr von polar
Found it a bit trickier than the last one, but still very enjoyable. 4 is my lucky number.. Just an fyi for the next one ;)

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