Cada oveja con su pareja
(Published on 3. July 2024, 19:46 by sujoyku)
In my opinion, this is one of the most challenging puzzles I have set so far. One of the testers suggested that it might have quite a narrow solve path. Therefore, I have decided to give some optional hints. I have tried to formulate them in such a manner that you still need to figure something out yourself. If you like to get more details or have questions, please do not hesitate to write a hidden comment. I like to thank Blashyrkh, MattDdraig and gdc for testing the puzzle. Also I like to thank Flinty for helping me with the code for the hints. Estimated difficulty is 4 stars. As always, your comments are much appreciated. I wish you joyful solving!
- Normal sudoku rules apply, i.e. each row, column and 3x3 region has to contain the digits from 1 to 9 once each.
- Cage ambiguity: Each cage is either a killer cage or a Rellik cage (which is which has to be determined by the solver). Each cage total in the grid appears in exactly two cages. For each total one of the two cages must be a killer cage and the other one a Rellik cage.
- Killer cages: Digits in a cage must sum to the clue in the top left.
- Rellik Cages: In a Rellik cage, any combination of one or more digits CANNOT sum to the value in the top left.
Example: A Rellik Cage with given value 6 may not contain (1,2,3), (1,5), (2,4) or a single 6.
Hint 1
Consider boxes 3 and 7 which are fully covered by cages. What sum have the digits in the Rellik cage? Which digit therefore cannot be contained in it?
Hint 2
Three high digits are forced into Column 1 in boxes 1 and 4 resp. in Column 9 in boxes 6 and 9. Which of the two cages can be the killer cage with total 20?
Hint 3
Because of a 123 triple in Box 3, the killer cage with total 16 may not contain 7, 8 or 9. Where can the high digits be placed in Column 7?
Hint 4
Once you have figured out which cages with totals 5 and 9 are killer and which are Rellik: Where can high digits be placed in Row 8?
Hint 5
You have filled the grid except for the central columns? Do not worry, you are on the home stretch. There is only one more classic sudoku technique required to complete the puzzle.
Here you can solve the puzzle online:
Solution code: Row 2 from left to right (9 digits in total)
Comments
on 4. July 2024, 23:10 by marcmees
Well constructed. The solve slowed down considerably after skidding through the 2 most obvious boxes. Now I read there were also hints but I'm glad I missed that. :-) Thanks for the nice idea.
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You are welcome, marcmees, thank you for your comment! Slowing down in this one is no shame as there are a lot of (little and not so little) tricks to figure out. I am glad that you enjoyed the puzzle.
Kind regards, sujoyku
on 4. July 2024, 16:00 by sanabas
Interesting rules and good fun. Easy to miss an elimination from the relliks that's needed to progress.
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Thank you for your comment, sanabas! I am glad you liked the ruleset and had a fun solve. And you are right: There are a lot of little steps that turn out to be important laying the ground for some follow-up deductions.
Kind regards, sujoyku
on 4. July 2024, 13:12 by sorryimLate
Wow, what a fantastic idea and execution! It keeps giving interesting deductions from beginning to end. That said, I didn't think it was as hard as I was afraid of, based on your introduction. I agree, the solve path may be quite narrow, but it always felt intuitive where to look next.
I think the hints are nice to have if you get stuck, but they seem to give away quite a lot in my opinion, so I would encourage to try without them. Thanks for setting this beauty! 3*
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You are much welcome, sorryimLate, thank you for your comment! I am glad that you enjoyed the puzzle. Also thanks for sharing your take on its difficulty. I think it depends heavily on your familiarity with the constraints (especially Rellik cages). And as there are so many little deductions - which are not hard on their own, but still have to be found - I thought 4 stars is a fair estimate.
Regarding the hints: It is my first attempt of offering some assistance and in order to be useful the hints have to give away at least some steps. If you suggest a way of improving them, I am all ears. Of course, everybody is invited to tackle the puzzle without them.
Kind regards, sujoyku
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You're absolutely right about the hints, I didn't mean there's anything wrong in them. I think they're a great way to make these puzzles more accessible to solvers with different levels of experience. Keep up the good work!
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Ah sorry, then it was a misunderstanding. I thought you meant the hints somehow were too extensive. Never mind. :)
Kind regards, sujoyku
on 4. July 2024, 11:52 by Bankey
Very original ruleset, and well-executed. Thanks, @ sujoyku :).
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Thank you for your kind comment, Bankey! I am glad that you liked the puzzle.
Kind regards, sujoyku
