Spiral Galaxy Sudoku with clues
(Published on 13. November 2021, 16:55 by PrimeWeasel)
Standard Sudoku and Spiral Galaxy rules apply - the numbers 1-9 appear once each in each row, column and 3x3 box, and every cell in the grid must belong to a galaxy. Galaxies have 180 degree rotational symmetry (in their shape, not their digits).
If you are not familiar with Spiral Galaxies, have a look here: Spiral Galaxy
One of the digits from 1-9 acts as the centre for each galaxy. (E.g. If it's 4, all of them are 4) The dots in the grid are the galaxy centres. Galaxies cannot have any cycles (a closed loop belonging to a galaxy) or cover any 2x2 region.
The sum of the digits in each and any tail around a galaxy must be equal. Digits may repeat within a tail. A tail is the string of cells that orthogonally connect to each other and the centre of its galaxy, not including the centre itself. If they branch out, they are still part of the same tail. Also, a 1x1 galaxy can be valid, having no tails at all.
If any 5 or more cells along a row belong to the same galaxy, the digits in those cells must read across in ascending order.
f-puzzle
A word from Weasel
On the 30th of October I started my mission of coming up with a solution for hamslice's Spiral Galaxy Sudoku with one clue. It took me a week of perseverance to get to a solution with the help of Sktx, but, unfortunately, I happened to find two solutions at the same time, which meant the puzzle wasn't unique.
I was both sad (for not finding it to be unique) and annoyed (for not finding it to be unique) so that I was quick to condemn the puzzle that has stood unsolved since june 2020. After my comments hamslice took down the puzzle, which I can fully understand, I apologize for being so straightforward with my grievances. I had a great time pondering all its implications and coming up with a workable grid. And I think I know in hindsight why it wasn't unique.
Which brings me to this puzzle. I have recreated all the logical steps it took me to come to one of my solutions for the posed problem, with added clues in order to make a 'simplified' logical path. I chose this solution cause there is something very special going on with this grid (which I imagine hamslice's solution grid must have as well.
This is not the greatest puzzle in the world, it's just a tribute to what I hoped to be the greatest puzzle in the world. It's made for all the solvers who spent hours on the original puzzle and are interested in seeing how such a puzzle could work.
Fun fact: When uploading the picture I got image id=000BAD which made me seriously doubt putting this online :)
Solution code: Row 8, column 2
Comments
on 12. November 2022, 22:12 by Andrewsarchus
Very beautiful puzzle.
on 1. August 2022, 07:53 by Vebby
Awesome! Particularly enjoyed the region building phase. Sticky middle but after a key deduction it resolved very satisfyingly. Hats off for slaying the original dragon and then creating a puzzle that works so beautifully!
on 31. July 2022, 23:42 by Niverio
The way the regions get built is completely magical!
on 2. July 2022, 08:28 by filuta
Wow, that was really cool, and also beautiful (and also feels kind of special, given the history of this puzzle).
Thanks filuta!
on 2. July 2022, 02:18 by Kafkapharnaum
That was a lot of fun, especially the coloring part, which turns out to be a lot easier than expected, but the sudoku part, wow, that was brutal at some point -- the breakthrough reminded me of Piatato's Vers la flamme, which is one of the puzzles that impressed me the most. How you managed to construct this, I got no idea, but after that breakthrough, that was smooth as butter
(Also I worked on this with filuta, each on our own for the coloring, then jointly for the sudoku, and he went to bed just before the breakthrough -- expect another solve on this soon! :D)
~ Thanks for solving and finally getting it rated, much appreciated! As for constructing, having solved the original, I got pretty much all I needed from it to make it unique. The hard part was developing a method to solve it first. I've been avoiding the Suspended Animation to be honest, I have opened it twice and then decided to postpone it twice, I will do it eventually, but it feels like a massive undertaking.
.............
That's perfectly fine! As you can see from the time since my first comment below, I didn't exactly rush to solve this one either, and if I hadn't solved it with filuta, it would have take me even longer. Just your interest alone in my puzzle is already greatly appreciated! :-)
on 21. June 2022, 04:02 by Kafkapharnaum
In solidarity and to repay you for your efforts on my puzzle, I'll be tackling this one - which seems real close to getting rated - as soon as I find the time. I've never done a Spiral Galaxy of any kind and it's guaranteed to take me multiple sessions (and Qodec + Polar's comments alone just make me want to run away in terror already XD)
- Well, good luck, I'm 'always' available (or Sktx if he's up for it) on discord if you need further Intel! I have done some thinking on the suspended animation but haven't really started yet!
........
Yeah I figured that could be the case, as there's no way you'll find the Still Life part all that hard after solving Sktx's puzzles!
~ Well, it's been a while :)
on 19. December 2021, 11:45 by PotatoAffair
What a puzzle! It took me quite some time but it's really satisfying to have finally finished it. Well done!
on 29. November 2021, 00:45 by Qodec
Fantastic! I'm really proud of having solved this!
on 24. November 2021, 21:35 by harrison
My goodness that was a hard puzzle! The final result is absolutely beautiful.
~I'm glad you made it! Thanks for the perseverance!
on 14. November 2021, 06:54 by bigger
@harrison it can have four tail. A tail has to start from the centre. A close loop means two different tails intersect with each other. In a word, a tail can forked But can't intersect.
on 13. November 2021, 22:42 by henrypijames
I assume a galaxy must consist of the center and the connected tails only? Because the current phrasing doesn't prevent a galaxy to contain unconnected cells, as long as they're rotationally symmetrical.
Otherwise, the galaxy around R3C6 could consist of these three cells: R1C4, R3C6, R5C8. The two unconnected cells aren't tails and don't have to obey any rules about tails. The galaxy itself is rotationally symmetrical, has no loop and no 2×2 clump.
~ You are right in your observation about galaxies, but that's not how Spiral Galaxy puzzles work. They consist of a centre with cells attached to them orthogonally. But I'll make some adjustments in the rules to clear that up, since Spiral Galaxies puzzles don't appear all that often
on 13. November 2021, 22:27 by polar
Beautiful construction! Hats off to you for solving the previous puzzle (twice!). I recall looking at that puzzle with no clue of how to even begin, so your efforts are beyond impressive to me. I can scarcely imagine your frustration regarding uniqueness.. Nice to see such a wonderful puzzle come from that situation - thank you :)
~Thanks for your lovely words, glad you enjoyed it!
on 13. November 2021, 20:36 by Sktx
Damn, even when I knew the early logic from working on the hamslice puzzle with you, and even knowing about the final grid, it still took me an hour ! But that was all purely logical from A to Z, with really cool logic along the way, and the result is splendid. Great job !
~The help was much appreciated and absolutely necessary! Glad you tagged along and thanks for working your way through this solve!
on 13. November 2021, 20:25 by bigger
I didn't realize the last galaxy killer was that long ago. Miss The good old days.
~ yeah, me too
on 13. November 2021, 18:58 by kolot
I didn’t even read the rules of the puzzle yet but I am laughing at the comments. :)
on 13. November 2021, 18:56 by bigger
@udukos But I already post a puzzle. At this point I just want the BIG
~ One day you will!
on 13. November 2021, 18:24 by udukos
@bigger If you hurry, you can get BAG, BAM, BAN, BAR, BAT, BAY. :)
~ Leave the CAT for Big_Tiger though!
on 13. November 2021, 18:04 by bigger
I'm really jealous. Getting a word id is so hard.
~ Very nice comment.
