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.
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.
How on earth do you create a puzzle like that? Coming up with the rules it's presumably simple to generate solutions with a computer program, but how do you then work out the cells which need to be filled in order to not only minimally describe a single correct solution, but also leave a reasonable deductive pathway to that solution?
I think that's what boggles me most about this, the deductive pathway that's been created by the puzzle creator is a complete joy in its unfolding.
This guys is my "ASMR" bedtime watching. I just love his overall demeanor and child-like thrill from puzzle solving. I can be wired when I start his video and by the end I'll be blissfully calm and head-clear. I think he has a tremendous talent of focus. As other posters have said, he can spot constraints so quickly. I still get a small kick out of spotting something before he does, though. Doesn't happen often, mind.
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.
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, 7],
[5, 9, 4, 8, 3, 7, 2, 6, 1],
[3, 7, 2, 6, 1, 5, 9, 4, 8],
[6, 1, 5, 9, 4, 8, 3, 7, 2],
[9, 4, 8, 3, 7, 2, 6, 1, 5]]
python3 game.py 7.47s user 0.15s system 97% cpu 7.801 total25 minutes you'll be okay with never getting back.
"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.)
This is clicking on an existential level for me.
Lex Fridman's podcasts in particular have been sort of forking in two directions lately, one on artificial intelligence, consciousness and just a somewhat muted wonder how the human mind operates and our present lack of understanding of how it comes together systematically to create our experience. The other is about physics and how the experimental and theoretical come together to try to give us a better understanding of the fabric of our universe.
For this video, in the former case it shows how plastic the mind can be. I'm probably about the same age as the guy in the video and honestly have been struggling with an experience of cognitive decline lately. To see how adaptive the brain is to not only develop grooves that accelerate analysis in the long form, but also adapt to new rules and constraints almost as quickly is really quite remarkable (and for me personally, encouraging).
His quick pattern analysis at the end uncovered the second case for me. This is obviously something we've seen in many other situations as well, but how a collection of 'particles' with multi-dimensional constraints can form order and even crystalline structure from almost nothing.
Very fun video to watch. Thanks for sharing.
There is something irreplaceable about the first time you solve a difficult puzzle, especially one that you anticipate to be daunting. As a Sudoku enthusiast (though not at Simon's level) this was surprisingly vicarious to watch for what's usually a silent solitaire experience. Well done!
For some reason this video ended up in my Youtube recommendations last week, and I clicked on it because the thumbnail caught my attention. Didn't regret it, and I've watched a few others. Another that was pretty interesting in the development of techniques to approach it: https://youtu.be/Zk4qNEDXFSw
Edit: Ah no, the first I saw was actually https://youtu.be/hAyZ9K2EBF0 which has a diagonal rule, and a magic square in the middle.
Now I want a making-of video by the creator of the Sudoku.
At the beginning I was wondering whether 9 and 1 were to be considered consecutive. It's not stated anywhere, but it seems that the solution has this property.
This was great fun! They have a new miracle sudoku[0] up since a couple of days, as well. Seeing him color the potential twos (aside from two wrongly colored squares) and then piece by piece ruling them out almost looked like a game of life, with new patterns emerging.
I get the feeling that he would be a very impressive programmer.
It did the follow up sodoku (a new miracle sodoku), which I think probably is a bit easier as it starts with 3,4 in a slightly more useful constellation.
I have to say while I'm not the biggest fan of normal sudokus the ones with extra rules are quite interesting.
And the cracking the cryptic channel has quite a bunch of such sudokus.
Ever since seeing this video I've been wondering if there's some deeper mathematical basis for this puzzle, because of the extremely regular pattern that it happens to produce.
For example, the way consecutive digits are actually in order, but separated by a single square (and looping around the edge of the board)
Here’s link to the puzzle:
https://cracking-the-cryptic.web.app/sudoku/tjN9LtrrTL
About the guide to controlling the interface for the game:
https://cracking-the-cryptic.web.app/how-to-play
(Links are little odd, if you want to find them yourself, just click the YouTube, view the video description, it’s the top link.)
I was just thinking the other day how I've never seen a YouTube video at the top of HN. along comes this video to prove me wrong.
I immediately saw what the full pattern was when he had half the 2s filled in and was wondering if he saw it and kept going through the solution for the purposes of the video, or didn't see it at all until the end.
That never ended up becoming clear and now I'm just left wondering.
Not a big sudoku fan, but wow! I might have under-estimated how exciting it can be.
and we have rotational symmetry! brilliant!
How do know if a certain puzzle is impossible (ie malformed)?
Any other puzzles with deep deductive reasoning where one can get better at through playing. One comes to mind: hexcells, any others?
puzzles and progamming - two of the best ways to while away the time.
This video was just fabulous to watch.
perverts.
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, I kind of shrugged at the fancy methods. But I suppose that is why I'm still just a mediocre programmer :)
The brute force method was basically move forward until you hit a dead end, backtrack, go forward again until you hit another dead end, etc.
Edit: I'm not being dismissive of people who implemented better solutions. Honestly, at the time I was amazed at their skill. But I still chuckle just because the problem is trivially sized for brute force methods, and would have to be scaled much larger to actually make more sophisticated methods worth the effort in any situation other than personal satisfaction and education. In a business situation in which you do not expect the problem to scale, spending more time for a sophisticated solver may not be worth the effort. But yes, Soduku is for entertainment and R&R
Using my CL based sudoku solver [1], I got the following solution. The solution is valid but different from what is shown in the video. IIRC, a sudoku board can have multiple solutions but anyone out here can explain why so? I am no sudoku expert or enjoying solving sudokus anyways!
[1] https://github.com/dmsurti/sudoku
```
(setf board
#(0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 1 0 0 0 0 0 0
0 0 0 0 0 0 2 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0))
```
* (sudoku:print-board (sudoku:solve board))
1 2 5 | 6 4 7 | 8 9 3
8 3 4 | 5 9 1 | 6 7 2
9 7 6 | 3 2 8 | 4 5 1
- - - - - - - - - - -
5 8 9 | 2 3 4 | 1 6 7
2 6 1 | 7 8 9 | 3 4 5
3 4 7 | 1 5 6 | 2 8 9
- - - - - - - - - - -
4 9 2 | 8 1 5 | 7 3 6
6 1 8 | 9 7 3 | 5 2 4
7 5 3 | 4 6 2 | 9 1 8
```
edit: formatting
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.