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The Miracle Sudoku [video]

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Re: The Miracle Sudoku [video]

#121

Post by tasuki »

kadoban wrote: post #92
matsemann wrote: post #59

Earlier quoted context omitted.

Yeah, I liked how he realized two possibilities for a number that were next to each other, also meant the box around it could be cleared. I really enjoy finding patterns like these in constraint games. After confirming the pattern for myself a number of times, the brain later just does it on autopilot. If people have tips for similar games I would be happy to try them. Edit, my tips: Simon Tatham's Puzzle Collection…

If you're into that feeling, learning a game like go might be something you'd enjoy. There's other parts to the game, but finding clever tactical moves is a huge rush of that. There's also books and sites with "go problems", chosen puzzle positions, for a quick fix (but only after you know the game a bit).

Hey I made a website with books full of go problems. It's become quite popular: https://tsumego.tasuki.org/

It's non-interactive not just because I'm lazy, but also there's some reasoning for why you should solve problems rather than click around and randomly try things out :)

Re: The Miracle Sudoku [video]

#122

Post by GreedCtrl »

thom wrote: post #116
rtpg wrote: post #104

Earlier quoted context omitted.

Basically the challenge is in finding the thought process that leads you to an answer. The kinds of puzzles done on this channel tend to be pretty tough. the designers of the puzzle usually make it so that there's really one good path for solving (and brute forcing _really doesn't work_ relative to thinking hard about the problem). There's a lot of stuff going on in this puzzle that's not at all present in normal sud…

I guess to me if still _feels_ a bit like brute force. You just go over all the squares and all the rules in a loop, adding and eliminating possible digits. There don't seem to be any sticking points where it's not clear how to make progress.

The "exploration and backtracking" you mention originally is the brute force method of solving sudoku by computer: recursive backtracking. If you want an example of sticking points, I'd recommend the Robin Hood sudoku:

https://www.youtube.com/watch?v=pdtWTg4LrqQ

It can be brute forced with enough patience, but the fun for me comes in developing intuition on where to look next. The hints of a sudoku have meaning: they lead to the completed grid. Finding the next step in the puzzle amounts to understanding some of its construction.

Re: The Miracle Sudoku [video]

#123

Post by cbsks »

matsemann wrote: post #59
aidos wrote: post #24

I almost didn’t watch that’s because who cares about someone solving a sudoku puzzle, but that was brilliant. That’s one happy solver; it was worth it just for the absolute joy he gets from it. Amazingly quick solving too. Good to watch him develop extra strategies during the process.

Yeah, I liked how he realized two possibilities for a number that were next to each other, also meant the box around it could be cleared. I really enjoy finding patterns like these in constraint games. After confirming the pattern for myself a number of times, the brain later just does it on autopilot. If people have tips for similar games I would be happy to try them. Edit, my tips: Simon Tatham's Puzzle Collection…

I am a huge fan of Simon Tatham's puzzles. His developer documentation [0] is absolutely amazing. All the puzzles are written in very high quality C with, in my opinion, a perfect ratio of comments to code [1].

I was hooked on his Tents [2] puzzle for a few weeks, then I started modifying the code to automatically fill in squares based on the tricks I found for adding constraints. Before I knew it, I had written a complete solver! Now I don't have to waste my time on it and I can get back to work :)

[0]: https://www.chiark.greenend.org.uk/~sgtatham/puzzles/devel/

[1]: https://git.tartarus.org/?p=simon/puzzles.git;a=blob;f=tents...

[2]: https://www.chiark.greenend.org.uk/~sgtatham/puzzles/js/tent...

Re: The Miracle Sudoku [video]

#124

Post by chrisshroba »

zwegner wrote: post #26

In case anybody sees this comment before the video: I'd highly recommend trying to solve the puzzle yourself. After you see the rules stated in the video, click the link in the info. It took me a bit longer than this guy, but it was a very fun puzzle.

Does anyone know of good places to look for similarly interesting puzzles? I'd recommend https://puzzling.stackexchange.com/ but I'm looking for others to supplement that!

Re: The Miracle Sudoku [video]

#125

Post by billfruit »

yesenadam wrote: post #89
billfruit wrote: post #64

Any other puzzles with deep deductive reasoning where one can get better at through playing. One comes to mind: hexcells, any others?

There's a whole world of chess composition/problems. You can even be a grandmaster chess composer or solver. Some composers are legendary in the chess world, e.g. Troitzky, Sam Loyd, Kubbel. Chess problems come in various kinds, and are a bit like cryptic crosswords - they seem impossible at first but there are customs, tricks, conventions which make them easier with experience. "The role of aesthetic evaluation in t…

What would be a good book to get into chess problems and the culture/aesthetics of them?

Re: The Miracle Sudoku [video]

#126

Post by carapace »

kryptn wrote: post #119
carapace wrote: post #111

Earlier quoted context omitted.

FWIW, "Boring Sudoku" a solver in Prolog w/ CLP(FD): https://swish.swi-prolog.org/p/Boring%20Sudoku.swinb - - - - I don't mean this in a critical way, just an observation. To me the video was boring because watching a human do machine work is frustrating (to me). (As fast and as clever as that fellow is, he's still so slow compared to a computer.) However, designing elegant constraint rules to encode the special cons…

> To me the video was boring because watching a human do machine work is frustrating (to me). I wouldn't think Sudoku is machine work. Yes, a machine can solve it, but it's not intended to be machine work.

It's intended as recreation, yeah, but to me watching that video was like watching someone carry large rocks without aid of a wheelbarrow.

Or like digging a large ditch without aid of a backhoe.

To me there is a clear hierarchy or graduation of puzzles. Metaphorically:

1. Ditch digging by hand.

2. Planning efficient ditch layouts to be dug by machines.

3. Designing new and better ditch digging machines.

- - - -

1. Solving Sudoku puzzles.

2. Designing new Sudoku puzzles (with additional constraints even.)

3. Designing e.g. CLP(FD) programs to solve all sudoku puzzles everywhere.

- - - -

What I'm saying is, Why don't people move up that hierarchy? Why is level 1 so fascinating to people?

I believe that anyone who can solve sudoku can program a computer, but they don't. Why not?

Re: The Miracle Sudoku [video]

#127

Post by kadoban »

tasuki wrote: post #121
kadoban wrote: post #92

Earlier quoted context omitted.

If you're into that feeling, learning a game like go might be something you'd enjoy. There's other parts to the game, but finding clever tactical moves is a huge rush of that. There's also books and sites with "go problems", chosen puzzle positions, for a quick fix (but only after you know the game a bit).

Hey I made a website with books full of go problems. It's become quite popular: https://tsumego.tasuki.org/ It's non-interactive not just because I'm lazy, but also there's some reasoning for why you should solve problems rather than click around and randomly try things out :)

Thanks for your site! I've been there before. I really like the Cho problems.

Re: The Miracle Sudoku [video]

#128

Post by kccqzy »

thom wrote: post #102
zwegner wrote: post #26

In case anybody sees this comment before the video: I'd highly recommend trying to solve the puzzle yourself. After you see the rules stated in the video, click the link in the info. It took me a bit longer than this guy, but it was a very fun puzzle.

I'd never done sudoku before and was a little disappointed to find it was so mechanistic. I'd sort of expected there to be some degree of exploration and backtracking, or perhaps having to solve multiple digits simultaneously while attempting to keep it all in your head. Is this puzzle representative of normal sudoku puzzles or do the additional constraints change it?

On the other hand, backtracking feels much more mechanistic to me. A dumb computer can guess and backtrack and check constraints with a simple algorithm. Humans ought to do better than that—with more logic and more deduction.

Re: The Miracle Sudoku [video]

#129

Post by nickysielicki »

carapace wrote: post #111
nickysielicki wrote: post #71

Here's a solver in python with z3: https://gist.github.com/sielicki/fd86d68733133f654128519b3c4... (note, most of the code coming from here, I just slopped together the additional constraints, https://ericpony.github.io/z3py-tutorial/guide-examples.htm ) $ time python3 game.py [[4, 8, 3, 7, 2, 6, 1, 5, 9], [7, 2, 6, 1, 5, 9, 4, 8, 3], [1, 5, 9, 4, 8, 3, 7, 2, 6], [8, 3, 7, 2, 6, 1, 5, 9, 4], [2, 6, 1, 5, 9, 4, 8, 3,…

FWIW, "Boring Sudoku" a solver in Prolog w/ CLP(FD): https://swish.swi-prolog.org/p/Boring%20Sudoku.swinb - - - - I don't mean this in a critical way, just an observation. To me the video was boring because watching a human do machine work is frustrating (to me). (As fast and as clever as that fellow is, he's still so slow compared to a computer.) However, designing elegant constraint rules to encode the special cons…

That's cool, but that doesn't solve this puzzle. It's just a normal solver unless I'm missing something.
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