Region Geometry X
(Published on 2. June 2022, 00:28 by kolot)
Here is another puzzle with the same rule set as my last puzzle Region Geometry. Many thanks to purpl for testing it. The puzzle Region Geometry had 8 question mark clues, 6 black 2 red, where one of the region constraints was relaxed for the red clues. This one has only 6 question mark clues, all black, but has an additional X in the grid. I couldn't achieve my goal of constructing a Chaos Construction sudoku with only question mark clues of the same type, but I am still very happy with this puzzle. It involves very similar logic with Region Geometry on the question mark clues, but the way regions are built is different. I believe this puzzle has a smoother solution path than Region Geometry. If you solve both puzzles, please let me know if you think so or not. I hope you enjoy the puzzle. Your comments and ratings are highly appreciated as usual!
RULES: Each row, column, and region must contain the digits from 1 to 9 exactly once, where each region is a set of orthogonally connected cells and must be determined by the solver. Cells separated by X must sum to 10. Not all Xs are necessarily given.
Clues outside the grid represent any integers from 1 to 9 inclusive, and they act as both skyscraper and numbered room clues with additional region constraints.
Skyscrapers: Considering each digit in the grid as a skyscraper of that height, clues outside the grid indicate the number of skyscrapers seen from that direction where taller skyscrapers hide the shorter ones. For each clue, all visible skyscrapers must be in different regions.
Numbered rooms: Clues outside the grid indicate the digit in the Nth cell from that direction where N is the digit in the first cell from that direction. For each clue, the first and Nth cells must be in the same region.
CHALLENGE: I would like to repeat the challenge I have written under the Region Geometry puzzle. Can anyone construct a 9x9 Chaos Construction sudoku with a completely empty grid, only question mark clues outside the grid that apply to their row/column (no diagonal clues), where the rule for all question mark clues is defined exactly the same way, and there is no other rule?
Solution code: Row 4 followed by column 7.
Comments
on 10. May 2024, 00:19 by Agent
Incredible! Some very cool geometric restrictions with this minimalistic setup, and the way the X resolved everything so smoothly was the icing on the cake.
on 23. February 2024, 22:37 by Myxo
Wow, another masterpiece! And somehow even smoother than the first one.
on 22. July 2022, 01:25 by MagnusJosefsson
Amazing puzzle just like the predecessor!
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Thank you!
on 9. July 2022, 18:43 by Piatato
Superb puzzle, just like I expected!
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Thank you!
on 11. June 2022, 21:35 by Elliptical
This is an incredible puzzle. Incredibly hard and incredibly beautiful. One of the hardest puzzles I ever solved and worth every minute of it. Kolot is slowly approaching the holy grail of puzzles.
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Thank you so much for solving the puzzle and for your great comment!
on 5. June 2022, 05:31 by cair
Brilliant puzzle!
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Thank you!
on 4. June 2022, 01:30 by peacherwu2
Harest I ever solved. Seems impossible at quite a few places. Wonderful, wonderful, wonderful!
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Wow! Thank you so much for the solve and for this lovely comment!
on 3. June 2022, 14:05 by Lizzy01
Very nice!
This one took me 118 minutes, which is shorter than the other one, and I didn't need a hint for this one, but it still felt just as hard.
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Thank you so much for the solve and the comparison!
on 3. June 2022, 09:08 by Jesper
Great puzzle! Very challenging, especially the second half.
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Thank you so much for the solve and for the kind feedback!
on 3. June 2022, 04:20 by henrypijames
You did it again! Solid 5 difficulty, even the X is really hard to make use of.
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Thank you so much for solving it and for your feedback! I appreciate it.
on 2. June 2022, 23:22 by marcmees
The solve of the first one definitely traced the path of its sequel at the start. It quickly turned into a completely different and incredibly minimalist beauty. Thanks
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Thank you for the solve and for your kind comment! Happy to see that you found it beautiful.
on 2. June 2022, 23:17 by DVFrank
Once again a quite incredible puzzle! Even though this one went down considerably faster than your first version, I found it to be be just as difficult. The beginning and later third felt a lot smoother though, but just as rewarding. Thanks for setting yet another treat! :^)
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Thank you so much for solving the puzzle, for your very kind words, and for your feedback on the difficulty and smoothness of the puzzle!
on 2. June 2022, 22:48 by deltameth
Wow, what an incredible puzzle. I loved the smooth flow and I hate how many times I made a mistake in logic and had to revert a bunch of steps.
Thank you!
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Thank you for your perseverance and for your kind words!
on 2. June 2022, 20:28 by Vebby
Just as good as its prequel! Maybe a touch smoother, but fairly similar in difficulty I thought. Thanks Emre :)
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Thank you so much for the solve, for your lovely comment, and for your feedback on the difficulty of the puzzle!
on 2. June 2022, 14:27 by Tilberg
It's really incredible how far one can get just with these question marks. Impressing setting!
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Thank you so much for the solve and for this lovely comment!
on 2. June 2022, 00:33 by purpl
Beautiful logic!
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Thank you!
