Chaos Deconstruction: Japanese Sum
(Published on 13. February 2023, 20:00 by Phistomefel)
Here are the rules:
- Shade some of the cells and write a number from 1 to 9 in every unshaded cell such that no digit repeats within a row or column. Shaded cells cannot contain numbers. A row or column does not necessarily contain every digit from 1 to 9.
- There are nine orthogonally connected sets of unshaded cells containing each digit from 1 to 9 exactly once, in the grid. Each unshaded cell is part of such a region and the regions may not touch orthogonally, but may touch diagonally.
- The clues outside of the grid are Japanese Sum clues. A number indicates the sum of the digits in a consecutive set of unshaded cells. The clues are given in the right order.
- A single '?' represents a single digit from 1 to 9. Combined with another digit, it can also be 0, as long as it is not the leading digit. E.g. '1?' could be any number from 10 to 19 and '?4' can be 14, 24, 34 or 44.
- '??' represents some number which is greater than 9.
- '*' represents any number of sets of consecutive unshaded cells with arbitrary sums including no unshaded cells at all.
- Every consecutive set of unshaded cell is accounted for by Japanese Sum clues.
Here you can find a link to solve the example online.
The actual puzzle is also available online via Penpa Plus. Have fun solving!
Solution code: Last row: S for a shaded cell and the respective number for an unshaded cell. For the example, the solution code would be "1632SSSS".
Comments
on 12. March 2024, 01:31 by Christounet
Superb puzzle ! Some deductions are really intricate and the way it resolves in the last regions is so satisfying. Thanks :)
on 23. February 2024, 11:54 by markopuzz
@Phistomefel I get it now! Thank you for your help.
on 22. February 2024, 23:21 by Phistomefel
@markopuzz: A "*" can represent basically anything. It can represent one group of shaded cells (like in column 1), it can be more than one groups of shaded cells (like column 4) or no group of shaded cells (like the first "*" in row 6). The reason it is there at all is just to be able say that all groups of shaded cells are accounted for by the clues.
on 22. February 2024, 22:25 by markopuzz
Can someone explain me rule number 6, one with "*"? Somehow I don't get it.
on 22. June 2023, 02:34 by Piatato
Awesome puzzle, with so many great steps. Very enjoyable throughout!
on 12. May 2023, 23:16 by Krokant
Heilige asiatische Addition, Batman! Was für ein Monstrum!
Den Einstieg in den Einstieg habe ich schnell gefunden. Aber der nächste Schritt hat auf sich warten lassen. Irgendwann kam dann DIE Erleuchtung. Zum Glück blieb es nicht bei der einen; im Laufe des Rätselns kamen noch mehr dazu. Ohne die wären aus Stunden wohl auch eher Tage geworden. Oder Wochen. :)
Das sind richtig, richtig tolle Japanische Summen. Großes Kino.
on 23. April 2023, 18:37 by peacherwu2
Made a mistake lower left and it took me two more attempts to fix...
on 2. March 2023, 06:38 by cha
Very Nice!
on 26. February 2023, 04:06 by BlueShifted
Sigh... It took me around 5 hours to spar with this monster. Your puzzles mostly require understanding a big story and then getting the break in from there. However, this one was sequential, still super brilliant as usual from you. Thanks this was so much fun, made my weekend :) .
on 24. February 2023, 23:26 by Prutsbeest
Wow, what a difficult but beautiful puzzle this! I'm going to sleep now, it's been a couple of hours :)
Thank you so much for setting this, it was absolutely lovely to solve!
on 24. February 2023, 16:28 by Klausku
Wow! Ich habe mich durchgekämpft. 5 1/2 Stunden auf mehrere Tage verteilt. Brilliant, genial und monstermäßig schwer. Danke für den wunderbaren Zeitvertreib. Ein herrliches Gefühl, wenn am Schluss jeder Clue abgehakt werden kann. Warum die 100% Bewertung nicht mehr da ist, ist für mich absolut nicht nachvollziehbar.
on 23. February 2023, 19:11 by h5663454
@glum_hippo
I'm sorry, I was really a little too excited just now.
But after Niverio made his voice on the forum, there seems to be no further news.
It seems they can't do anything about it either.
on 23. February 2023, 18:59 by glum_hippo
@h566 could you possibly refrain from spouting this nonsense on a puzzle page? This is what the forums are for.
on 23. February 2023, 16:35 by Lizzy01
Very nice, and VERY hard! I started working on it the day after it was published, and it took me multiple hours, spread across the week to finally finish it!
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Wow, that is some dedication! Thank you, Lizzy01! :)
on 23. February 2023, 15:05 by madhupt
This puzzle is beautiful beyond description. Deserves a 120% rating. A true masterpiece. Thanks for giving us so much joy.
on 18. February 2023, 19:59 by stayal
Broke the puzzle several times, but I'm so glad I didn't give up. The * rule is something I was new to and it really complicated the logic but it was truly brilliant.
on 17. February 2023, 23:25 by thoughtbyte
Lovely puzzle as always, thanks!
on 17. February 2023, 20:31 by pianobarry87
This was such a joy to solve! Extremely fresh logic with a theme that kept on giving.
on 17. February 2023, 03:54 by cmb
Beautiful, wonderful!
This puzzle is totally off the charts.
on 16. February 2023, 15:37 by Phistomefel
Thank you so much for all the wonderful feedback, folks! I am very happy to read that you've enjoyed the puzzle. :)
on 16. February 2023, 15:19 by Al Fresco
Wow. What a fantastic puzzle, crammed with so much wonderfully creative logic :) Thank you Phistomefel
on 16. February 2023, 07:19 by Agent
Incredible puzzle! Very challenging, but consistently delightful to solve.
on 15. February 2023, 15:17 by wildbush7
Amazing puzzle! Absolutely loved it. I'm still kinda new to this whole sudoku world but I can see why Phistomefel is held in such high regard.
on 14. February 2023, 14:13 by ONeill
Brilliant puzzle. Thanks! It would be great to watch Simon have a go at this, let’s hope :)
on 14. February 2023, 12:49 by Playmaker6174
By the way, I should highlight some of my favorite parts/clues from this puzzle: the 9 clue in col 4, the ?? clues in col 5 and 7, the 16 clue in row 7, pretty much 3 top rows and 2 bottom rows :)
on 14. February 2023, 12:42 by Playmaker6174
One of the nicest and most satisfying puzzles I've solved in 2023 so far! (still 10 months left but yeah, you know :P)
A really long and consistent solve path, yet everything works and clicks so well together: from the exceptional opening sequence to the wonderful mid solve and then to the mind-blowing ending. BUT GOOD LORD, that ending took me *way way too long* to spot the mistakes that I'd done earlier and I should've finished the puzzle for like 100 mins sooner, it almost ruined my joy after experiencing such a profound solve path :o
on 14. February 2023, 10:58 by Phistomefel
Thank you for the very kind feedback, everyone!
on 14. February 2023, 09:10 by Phistomefel
Rule clarification
on 14. February 2023, 07:03 by RJBlarmo
Very fun and tricky puzzle! Definitely hoping to see more like these in the future!
on 14. February 2023, 04:27 by Vebby
Loads of fun! Thanks Phisto, am glad to solve another construction puzzle from you, they're my favourite kind! :)
on 14. February 2023, 03:43 by polar
What a delight to see a pencil puzzle hybrid from you again - they are always my favourite puzzles of yours to solve :) Certainly worth the wait, but.. I will always hope to see more! Thank you very much!
on 13. February 2023, 22:24 by Jesper
Wonderful puzzle! I had high expectations starting the puzzle, and they were not disappointed :)
on 13. February 2023, 22:00 by KNT
@Phistomefel apologizing for a great puzzle? That's a new one. But without spoilers, the configuration of the last couple of regions definitely looked extremely prone to breaking. I do not envy the trouble it took to get it to resolve as nicely as it did.
on 13. February 2023, 21:51 by Myxo
Großartig und spannend bis zum Ende :)
on 13. February 2023, 21:51 by Niverio
Gorgeous puzzle! It was just a long and fun solve, I didn't find the individual deductions brutal at all, and many of them were extremely satisfying. Thanks a lot for this gem, Phistomefel!
on 13. February 2023, 21:37 by Phistomefel
Thanks a lot, KNT! Sorry that it took me a while, but the ending kept giving me a headache or two. I am all the more happy to hear that you enjoyed the puzzle thoroughly.
on 13. February 2023, 21:34 by KNT
So this is what you were mentioning to me a couple months back ;)
Awesome puzzle. Thoroughly enjoyed it start to finish. I'm definitely biased, but easily one of my favorite puzzles from you. Thank you so much!
