Think outside the snake
(Published on 25. June 2022, 21:13 by filuta)
The idea of this ruleset came to me when I solved brilliant Nessie by henrypijames and Nordy and saw the huge snake they created leaving behind many tiny pieces of the grid. That really got me thinking whether one can use it to create killer cages.
I quickly made a 6x6 prototype (the example below), but then got very doubtful about the 9x9 version. But in the end it worked out somehow and I hope you will like it.
Big thanks to ctc discord users Dave McB, Jay Dyer and Geryon for their test solves and feedback on various versions of this puzzle.
Have fun solving, I will be happy to read your comments/feedback.
Rules:
Normal sudoku rules apply. In addition to that draw a one cell wide snake (non looping or branching string of orthogonally connected cells with two ends - head and tail) that may not touch itself orthogonally such that:
-the snake divides the rest of the grid into regions consisting of orthogonally connected cells, each of which sums to the same total and contains no repeated digits,
-all given digits belong to the snake and may not decrease when read along the snake from head to tail.
Example:
On the solved grid on the right hand side you can see the snake in gray, the regions (essentially killer cages) outside the snake in blue - they all sum to the same number, in this case 6, and the given digits make a non-decreasing (in fact increasing) sequence 12345 when read from the head of the snake (r3c4) to its tail (r3c6). Link to solve the example puzzle here.
You can solve the puzzle online via:
penpa+ link (or a special pride month edition)
ctc app link
f-puzzles link
Solution code: Digits not on the snake in rows 4, 5 and 6 (just digits, no commas or spaces).
Comments
on 27. January 2025, 23:51 by Christounet
Great ! Not as hard as expected but superb construction. Thanks :)
on 13. June 2024, 17:08 by Styku
I have no idea how you create these masterpieces one after another but thank you for doing it. I had so much fun :)
on 31. May 2024, 19:11 by Samish
Funnily my longest freeze on your puzzles since I think it was the first one I tried a couple years ago. I reckon now it was not as hard as I thought :D
on 21. May 2024, 09:48 by Silverstep
I think this is the most vibe-based solve I've ever done on a puzzle (as opposed to rigorous proof-based solve). It's interesting that Simon solved this one; iirc the recent snake puzzle - "Dutch Baby" by glum hippo - was featured by Mark.
on 7. March 2024, 15:45 by wullemuus
My first snake puzzle- due to its clever construction I only made minor mistakes in colouring. With the correct restart all of the given digits became a new meaning (as always in your puzzles)- really great!
on 1. July 2022, 05:45 by Kafkapharnaum
"Stunning", "beautiful", "incredible" -- that pretty much sums it! In a word, the usual for a filuta puzzle! ;-) But I gotta say, my favorite part was the 'meta' in it -- not only am I a sucker for this kind of thing, but it kind of helped me solve it quickly here hehe. The only disappointing thing here is that my solve didn't get it rated :-/
...........
haha, thank you so much for such a (meta) comment :o)
on 28. June 2022, 12:30 by Yawnus
What an incredible construction!!
.............
Oh, thank you, happy you liked it so much!
on 27. June 2022, 01:35 by Nordy
Wow, wow, wow!! I am awestruck by this puzzle. The solve was a beautiful journey with a variety of different stages—all simultaneously captivating and challenging (and smooth!). Straight to my favorites, and I’ll definitely be recommending this to CTC.
..............
Oh, wow, thank you so much!
on 26. June 2022, 19:00 by Piatato
Really a stunning construction! Amazingly clean, both the solve itself and of course the miraculous looking setup. Not horribly difficult either, definitely a nice break after your previous one, haha! :D
..............
Thank you so much!
on 26. June 2022, 14:51 by filuta
slight reformulation of the rules
on 26. June 2022, 04:07 by tryote
It’s a very nice puzzle. :)
..............
Thank you.
