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The Miracle Sudoku [video]

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11–20 of 150 posts

Re: The Miracle Sudoku [video]

#11

Now I want a making-of video by the creator of the Sudoku.

I wonder how much of that is programmed/automated and how much work is still being done manually... Backtracking and eliminating numbers can be easily automated.

I made a sudoku solver back when I was in school. It's quite simple and almost a textbook case for backtracking. Even brute-force algorithms are instantaneous on the hardest puzzles.

Re: The Miracle Sudoku [video]

#12
The lightning speed of his observing standard rules across the board is impressive but expected after months of practice. The agility with which he picks up new rules and starts working with them is sign of a beautiful mind. This was a pleasure to watch.

Re: The Miracle Sudoku [video]

#13

As a college project in C, we were to write a soduku solver. Smart people solved it by programming in fancy heuristics. Not being smart, I just brute forced it...though I tried to be fancy by representing the data at the bit level. I doubt it made it any faster lol. That said, when the hardest Soduku problems in the world succumbed to a brute force search to my lame program in less than a few something something ms,…

Wouldn't brute force be enumerating all possible combinations of numbers until you find one where all sums are correct? Your approach with backtracking sounds more fancy

Re: The Miracle Sudoku [video]

#14
post #13

As a college project in C, we were to write a soduku solver. Smart people solved it by programming in fancy heuristics. Not being smart, I just brute forced it...though I tried to be fancy by representing the data at the bit level. I doubt it made it any faster lol. That said, when the hardest Soduku problems in the world succumbed to a brute force search to my lame program in less than a few something something ms,…

Wouldn't brute force be enumerating all possible combinations of numbers until you find one where all sums are correct? Your approach with backtracking sounds more fancy

It was a long time ago, but I think I randomly filled in numbers, save if numbers were already used in each row or column, then when it reached an impossible solution, it would work backwards one level, trying new numbers. If it ran out of numbers, it would go back two columns, and try a new number.

I doubt it was anything fancy. At the time, it bent my mind into knots. Programming is a wonderful mind trainer.

Re: The Miracle Sudoku [video]

#15

As a college project in C, we were to write a soduku solver. Smart people solved it by programming in fancy heuristics. Not being smart, I just brute forced it...though I tried to be fancy by representing the data at the bit level. I doubt it made it any faster lol. That said, when the hardest Soduku problems in the world succumbed to a brute force search to my lame program in less than a few something something ms,…

> when the hardest Soduku problems in the world succumbed to a brute force search to my lame program in less than a few something something ms, I kind of shrugged at the fancy methods.

I think you're coming off as dismissive, which is why you're getting downvoted. Puzzles like these have the purpose to entertain a human solving them, and they do that pretty well.

If you seek entertainment in developing algorithms to solve these puzzles, you should adjust your challenge to modern computers: Up the size to 100x100 or more, see how your algorithm performs, and go from there. Spoiler: NxN Sudoku is NP-hard (NP-complete, to be precise), so have fun - maybe you'll even win a million dollars.

Now, if you want to really challenge yourself: Write an algorithm to create Sudoku puzzles that have a unique solution and as few initial numbers set as possible. Maybe you'll even improve your coding skills beyond mediocre. ;)

Re: The Miracle Sudoku [video]

#17
post #15

As a college project in C, we were to write a soduku solver. Smart people solved it by programming in fancy heuristics. Not being smart, I just brute forced it...though I tried to be fancy by representing the data at the bit level. I doubt it made it any faster lol. That said, when the hardest Soduku problems in the world succumbed to a brute force search to my lame program in less than a few something something ms,…

> when the hardest Soduku problems in the world succumbed to a brute force search to my lame program in less than a few something something ms, I kind of shrugged at the fancy methods. I think you're coming off as dismissive, which is why you're getting downvoted. Puzzles like these have the purpose to entertain a human solving them, and they do that pretty well. If you seek entertainment in developing algorithms to…

Good point. Thanks for bringing that up. I've edited my comment to bring context to my perspective.

Re: The Miracle Sudoku [video]

#18
"Once you eliminate the impossible, whatever remains, no matter how improbable, must be the truth."

Impressive work from a board that initially appears too open-ended to solve but turns out to have sufficient constraints.

Well worth watching. (Aside: the solver reminded me oddly of Professor Falcon.)

Re: The Miracle Sudoku [video]

#19
post #3

25 minutes you'll be okay with never getting back.

You can also if you want turn the playback rate up of the video and have the same satisfaction in half the time :)

I recently started increasing playback speed on many videos I watch. It's really hard at first, but I quickly got used to it, to the point where I now use an addon to increase playback speed to 3-6x where appropriate.

When there's something complicated, or something I want to enjoy and savior, I jump back and slow down.

This is an incredible time saver.

I got inspired to do this by observing a blind programmer use a screen reader with insane speeds.

Re: The Miracle Sudoku [video]

#20
post #5

My favourite part is his own disbelief as he ... spoiler ... continues to solve it. A few minutes later... when the first three on the board causes a cascade of solvable cells after a build up of deduction. Amazing.

He also said he was closed to ending the recording because he thought he was being trolled by the creator.

It was fun seeing him slowly realize that it was not a joke at all.

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