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Show HN: I made a deceptively simple but hard sliding puzzle
- mcdonje 4y agoThe medium puzzle is just like the torus puzzle in the Exponential Idle app. Solving help: https://exponential-idle.fandom.com/wiki/Minigames#Torus_Puzzle https://exponential-idle.fandom.com/wiki/Minigames#Torus_Puz...
- CodeIsTheEnd 4y agoVery similar to a game posted a couple months ago: https://news.ycombinator.com/item?id=30956775 https://news.ycombinator.com/item?id=30956775 (368 points, 124 comments)
- amenghra 4y agoI know, the hard level is however novel. I started prototyping this game several weeks ago but Shubham beat me to the punch.
- alas_141 4y agoI liked it. Very reminiscent of a rubik's cube. I found it's easier to make solid stripes and manipulate from there instead of going for the checkerboard right away.
- froh 4y agoWould it make sense to increase the difficulty more gradually? And independent of each other? Like size, number of colors, degrees of freedom, individually, instead if just easy medium hard, with presets?
- amenghra 4y agoThat was my initial idea (if you peek at the code, you’ll see it’s simple to create a 2-color + hard-mode). But it turns out that hard is quite hard, even with just 2-colors. So I picked 3 instead of 4 levels.
- tontonius 4y agoNice little game! Took me a few minutes to figure it out (I think having played with Rubiks cube helped somewhat)
- MrDrDr 4y agoVery nice - the explainer was helpful. Just lost an enjoyable 30mins :)
- captn3m0 4y agoQuixo (the game this seems to be based on) is also deceptively simple but Exptime complete (https://www.sciencedirect.com/science/article/pii/S002001902030082X https://www.sciencedirect.com/science/article/pii/S002001902...) and was solved after 2 decades (draw at optimal play on a 5x5 board, win for first player on smaller boards): https://arxiv.org/abs/2007.15895 https://arxiv.org/abs/2007.15895
- amenghra 4y agoNever heard of Quixo, thanks for sharing. My domain name was picked randomly a decade ago among the remaining short-ish names -- being similar in name is a coincidence.
- captn3m0 4y agoI assume that the name was a nod to the original game, my bad. I looked a bit for similar puzzles, and it seems this class of puzzles has a better name: A “Toroidal Sliding Block Puzzle”[1] [1]: https://puzzlingiphone.wordpress.com/2008/11/22/toroidal-sliding-block-puzzles/ https://puzzlingiphone.wordpress.com/2008/11/22/toroidal-sli...
- amenghra 4y agoToroidal Sliding Puzzle => chefkiss emoji
- dane-pgp 4y ago> (draw at optimal play on a 5x5 board, win for first player on smaller boards) Somewhat relatedly, I keep wondering how board size affects the game of chess in particular. It seems that a 1x8 board definitely leads to a stalemate (because the pawns in front of the kings would block each other), but at some point adding new columns (with the relevant pieces) makes the game impossible to exhaustively search, and at least plausibly introduces the ability for one of the players (presumably white) to win with perfect play. That ability for a winning strategy to emerge just beyond our ability to compute is somehow tantalising.
- shaneos 4y agoFun and deceptively difficult, nicely done!
- s-video 4y agoI felt so cool for beating it and then I saw "Current level: Easy"
- TOMDM 4y agoAgreed, I thought I had it cracked when I noticed that I just needed to get the spacing right on Easy, but man the difficulty is a cliff going into medium. EDIT: Oh Ok, Medium isn't that hard either, much harder than easy though, just figuring out the last "row" is to toothsome part.
- mirceal 4y agoEasy and Medium are doable. Hard is when the challenge begins!
- anderskaseorg 4y agoThe medium level is the same as carykh’s Loopover: https://www.youtube.com/watch?v=95rtiz-V2zM https://www.youtube.com/watch?v=95rtiz-V2zM, https://loopover.xyz https://loopover.xyz.
- mihaic 4y agoA few years back we had a programming challenge to solve the generalized medium puzzle. If you want to try solving it through code check it out here: https://csacademy.com/contest/archive/task/circular_shift_sort https://csacademy.com/contest/archive/task/circular_shift_so... It also has a detailed description of the solution in the more complicated cases, depending on the parity of each dimension.
- reportgunner 4y agoThe easy mode felt like a rubik's cube lite, I enjoyed it !
- lisper 4y agoThat's not a coincidence. The mathematical structure of both puzzles is essentially the same. The moves in both puzzles form a non-abelian group, which is the source of the challenge. See http://web.mit.edu/sp.268/www/rubik.pdf http://web.mit.edu/sp.268/www/rubik.pdf
- lisper 4y agoIf this puzzle reminds you of a Rubik's cube that is not a coincidence. The mathematical structure of both puzzles is essentially the same. The moves in both puzzles form a non-abelian group, which is the source of the challenge. See http://web.mit.edu/sp.268/www/rubik.pdf http://web.mit.edu/sp.268/www/rubik.pdf In fact, a fun meta-puzzle is to find a three-dimensional analog to this two-dimensional puzzle.
- bradrn 4y ago> In fact, a fun meta-puzzle is to find a three-dimensional analog to this two-dimensional puzzle. I believe this puzzle is equivalent to a Ehovxf phor ba n gbehf (rot13).
- malf 4y agoIt’s always a gbehf
- enchiridion 4y agoCan someone explain that notion?
- danbruc 4y agoNo notation, ROT13 encryption [1]. [1] https://en.wikipedia.org/wiki/ROT13 https://en.wikipedia.org/wiki/ROT13
- theideaofcoffee 4y agoMy first thought was the same, “ah it’s just a group puzzle like a rubik’s”. In my case, understanding the math doesn’t make up for me being completely useless in solving it.
- Jill_the_Pill 4y agoWhereas I solved it by instinct and am still not sure how. Maybe it is better to be lucky than good!
- boobsbr 4y agoThis game has been invented before. Not a dunk on you, people come up with similar or identical ideas all the time without knowing at all about previous instances of the idea. I first learned about this game from a YouTuber named Cary KH, he named his game Loop Over. https://youtu.be/95rtiz-V2zM https://youtu.be/95rtiz-V2zM
- LudwigNagasena 4y agoI was developing a similar game in Unity but decided to go further and add portals, rotations, splitting and other mechanics. Unfortunately, I have never managed to polish it (those 20% that take 80% of time, duh). I hope one day someone will implement something similar.
- jcfields 4y agoThere’s a Japan-only game for the Sega Game Gear called Kinetic Connection that plays similarly but involves rearranging a scrambled picture rather than moving colored blocks into a pattern. https://segaretro.org/Kinetic_Connection https://segaretro.org/Kinetic_Connection “Game 3” is the mode that rotates rows and columns like a Rubik’s Cube. There are probably earlier examples, but that’s the one that I’m familiar with. I imagine a clever person could adapt it into a simple word game as well. Old computer and console games are a gold mine for ideas for simple puzzle games.
- DerekL 4y agoThe hard level is the same thing as The Nowotnik Puzzle, a ZX Spectrum game from 1983. https://www.emulatorgames.net/roms/zx-spectrum/nowotnik-puzzle-the-1983-phipps-associates/ https://www.emulatorgames.net/roms/zx-spectrum/nowotnik-puzz... https://www.youtube.com/watch?v=sTLeI5QS8Qw https://www.youtube.com/watch?v=sTLeI5QS8Qw
- shikoba 4y agoNice game, but not really difficult. Try to implement SquareMinx instead ;)
- deleted 4y ago[deleted]
- amenghra 4y agoDid you try the hardest level?
- shikoba 4y agoYes, it was easy. I know how to solve a lot of twisty puzzles, I have a lot of experience. Yours is an easy one. Squareminx, is the real monster. edit: you put tiles at random for shuffle? It's not correct for the hard level. Only even permutations are accessible. edit: maybe I was tired when counting my permutations, forget the last edit
- amenghra 4y agoThe initial position starts from the goal and makes 100 random moves. So it’s guaranteed to be solvable.
- myaccount80 4y agoWow. Back in high school (~2011) I made this game as an ios app. I remember I published a video on YouTube and a few months later I found a copy on the App Store. Maybe it was just a coincidence. Unfortunately I don’t find my video on YouTube anymore, can it be that YouTube deletes old videos ?
- mdaniel 4y agoWhile I don't suffer from red-green colorblindness, it does actually hurt my eyes. One might consider offering a color switcher since as best I can tell they just need to be different from one another for the puzzle to work
- myfonj 4y agoIf you have some userstyles / userscript manager or can put user CSS into your browser, some patchy CSS: https://userstyles.world/style/4975/alok-s-sliding-puzzle-custom-colors https://userstyles.world/style/4975/alok-s-sliding-puzzle-cu... (It will break the moment author will change inline style.)
- mdaniel 4y agoIf I was going to go tho that trouble, I'd just build it locally (https://github.com/alokmenghrajani/sliding_puzzle https://github.com/alokmenghrajani/sliding_puzzle) My comment was to bring the red-green choice to the author's awareness, not to use HN as a complaint forum
- myfonj 4y agoSure, and my response was to provide simple POC to try some alternative hopefully more accessible appearance on top of live version for folks with colour vision troubles and potentially for the author as well.
- myfonj 4y agoAnyway, if you happened to peek at the illustration of the POC (used contrasting light / dark colours, plus patterns and softened letters of corresponding "inversion" [0]), do you think it is an improvement? Author of the game also updated the contrast [1], so now it is light blue versus slightly darker violet, but still with same default (usually black) text colour [1]. Do you like it better? Or would you prefer classical black versus white or something in this lines? [0] https://userstyles.world/api/style/preview/4975.webp https://userstyles.world/api/style/preview/4975.webp [1] https://github.com/alokmenghrajani/sliding_puzzle/commit/20caae33f7238c114d8da76ee0b5748733b49012 https://github.com/alokmenghrajani/sliding_puzzle/commit/20c... [2] https://github.com/alokmenghrajani/sliding_puzzle/raw/main/screenshot.png https://github.com/alokmenghrajani/sliding_puzzle/raw/main/s...
- Perez418 4y agoNice! At first I didn’t realize I had to match the small image, lol.
- teekert 4y agoThe easy one is solved simply by going for an all red band in the middle first (which is easy) and then the end situation is very close.
- aronhegedus 4y agoI struggled with the easy, then found a method for medium, and then medium was easy:) I can solve rubiks cube <30 seconds, and it definitely reminds me of it. Thanks!
- ouid 4y agoheres a non-constructive solution for the medium puzzle. the commutator of a row move a and a column move b (defined [a,b]=aba^-1b^-1). is a three cycle. it is not hard two see that any three cycle is conjugate to either a commutator or a product of two commutators [a,b]*[-a,b]. the three cycles generate the alternating group, which is maximal in Sn. but the group action also contains a 4 cycle, which is not in the alternating group. so the action must be all of Sn.
- pmarreck 4y agowhy has it taken this long for someone to come up with a 2D analog to the 3D Rubik's Cube? :O
- fortysixdegrees 4y agoI was finding this hard then wanted to see how long it would take to solve just quickly sliding randomly. Turns out very quick! If the number of moves was limited this wouldn't work
- efxhoy 4y agoThanks OP! I had a shitty day and this was really nice.
- amenghra 4y agoSorry to hear about that :( hope things get better!
- lovetocode 4y agoPretty cool! I was able to solve it fairly quickly. It immediately reminded me of how you would solve a rubiks cube.
- danbrooks 4y agoEasy/medium weren't that hard. The smooth UI helps quite a bit.
- aghilmort 4y agogroup theory aside, the elegance of sliding implementation is such that it feels like just humming along playing with Turing tapes that can act on each other in some nice smooth way; that's not to say it's a precisely accurate analogy, more that it just feels nice in some intuitive CS / math sort of way the other was that found it easiest to move to known state and then solve, like an intermediate canonical isomorph instead of solving directly as human without machine group theory super rotators
- buzzdenver 4y agoAny hints on how to solve even the easy one? I did map out what a sequence like right->down->left->up does, but feels like I'm still missing a step at least.
- amenghra 4y agoTry to use your sequence to build a row at a time.
- niknoble 4y agoFor the easy and medium, it seems like you can work outwards from the top left corner, solving progressively larger squares. 1×1, 2×2, etc. Once one of those squares is correct, you never have to touch the rows or columns in that square again. Probably not a perfectly efficient strategy but it makes it easier to think about.
- helsontaveras18 4y agoHave the first two rows figured out on hard but can’t seem to move past that. Any ideas?