SudoCue Users

The Universal Sudoku Player

Glyn wrote:If anyone can generate Clueless variants perhaps they can post them for everyone in the meantime. A poser for those with automated solvers perhaps, and dissecting previous puzzles for their underlying construction might keep everyone amused in the meantime.

mhparker wrote:Unfortunately, I can't create Clueless puzzles (Explosion or otherwise), but maybe someone else around here could (hope you're still listening, J-C! )?

I do have a fast brute force Sudoku solver, but a brute force solver is merely useful for standard 9x9 Sudokus. Solving a Ruud Clueless Sudoku using a brute force solver takes not only one but many, many lifetimes http://cid-c136798e52d0119c.skydrive.li ... dea%20.doc and gives you no indication of the difficulty of the puzzle.

Generating Ruud Clueless Sudokus is not an easy task and requires a very fast solver with several solving techniques implemented and some good ideas as how to generate a good start grid, otherwise it will take too long to generate Clueless puzzles. Ruud’s software for generating and solving Sudokus is very likely the very best. He is capable of generating virtually any kind of Sudoku and has to my knowledge more solving techniques implemented than anybody else.

I have the absolute highest respect for Ruud’s Sudoku software.



Since I like to solve Sudokus, especially larger ones with many interconnected 9x9 Sudokus without having to use paper and pencil, I have for many months now been programming a "universal" Sudoku helper called "The Universal Sudoku Player" (TUSP). (So far I have spent approx 1.500 hours coding some 35.000 lines of code including blank lines and too few comments.) I hope to have the first release finished in a couple of months and I will give it away for free.

You can find more information about the "The Universal Sudoku Player" here: http://www.sudocue.net/forum/viewtopic.php?p=4639#4639

I don't want to sound rude but how much further do you want to derail this thread?

I think you should have created a new thread for your upcoming software since this thread was first about the missing clueless explosion, then Ruud's whereabouts and now this. I don't think it should become chitchat.

Afmob wrote:I don't want to sound rude but how much further do you want to derail this thread?

I think you should have created a new thread for your upcoming software since this thread was first about the missing clueless explosion, then Ruud's whereabouts and now this. I don't think it should become chitchat.

You have a very valid point, I'm sorry about posting it here in this thread. Since I'm not a moderator I cannot move it, but I have started a new thread here http://www.sudocue.net/forum/viewtopic.php?p=4639#4639

Apologies
Børge

Børge wrote:The Universal Sudoku Player

Glyn wrote:If anyone can generate Clueless variants perhaps they can post them for everyone in the meantime. A poser for those with automated solvers perhaps, and dissecting previous puzzles for their underlying construction might keep everyone amused in the meantime.

mhparker wrote:Unfortunately, I can't create Clueless puzzles (Explosion or otherwise), but maybe someone else around here could (hope you're still listening, J-C! )?

I do have a fast brute force Sudoku solver, but a brute force solver is merely useful for standard 9x9 Sudokus. Solving a Ruud Clueless Sudoku using a brute force solver takes not only one but many, many lifetimes http://cid-c136798e52d0119c.skydrive.li ... dea%20.doc and gives you no indication of the difficulty of the puzzle.

Yes, I'm still listening.

I too have brute force solvers using DLX / Dancing links. I also made different versions for killers using different approaches. But I didn't program overlapping sudoku yet.

Børge, reading your doc, I immediatly noticed you're splitting the whole clueless problem into 9 separated / disconnected 3x3 sudokus. I believe it would be much better to setup and solve only one DLX for the whole problem by connecting overlapping houses into the same DLX candidate row.

I will give it a try... later...

BTW a better place to discuss programming is the Sudoku Programmers Forum

Hi guys,

As Afmob correctly points out, this thread has now lost its focus. I therefore suggest that any further discussion on Ruud's whereabouts is transferred to the other thread here.

Børge : Thanks for posting that information on your TUSP and for the screenshots. Always good to get an insight into what other forum members are up to!

Jean-Christophe : Likewise, thanks for replying to my original wink re: Clueless creation.

Jean-Christophe wrote:Børge, reading your doc, I immediatly noticed you're splitting the whole clueless problem into 9 separated / disconnected 3x3 sudokus. I believe it would be much better to setup and solve only one DLX for the whole problem by connecting overlapping houses into the same DLX candidate row.

I will give it a try... later...

Jean-Christophe, you could be right. My brute force solver is not DLX based. I have skimmed through Knuth's DLX paper, but I have to take more time to fully understand it.

My main point is however that IMHO using a brute force solver to generate puzzles is not a good idea since you have no way of measuring the puzzle’s difficulty.

Børge wrote:While we are waiting for Clueless Explosion 86 I have taken the liberty of reformatting the Black Friday gattai-21 puzzle Ruud posted on www.sudocue.net/special.php July 13, 2007. My reformatting allows you to write pencil marks. So if you haven’t solved it yet you may want to give it a try.

There are four versions:
BlackFriday.png (Clues have a light yellow background)
BlackFriday_cbg=gbc.png (Clues have the same background colour as the grid)
BlackFriday_withPencilMarks.png (With computer generated pencil marks and clues with a light yellow background)
BlackFriday_withPencilMarks_cbg=gbc.png (With computer generated pencil marks and clues with the same background colour as the grid)

I will delete the files in a couple of days!!!

Why did you delete these sooo soon??? I was just about to tackle this and
it's gone! AAAGGGGGG.....

Is it possible to repost them for a week?

EDITED due to double post

lynn893 wrote:

Børge wrote:While we are waiting for Clueless Explosion 86 I have taken the liberty of reformatting the Black Friday gattai-21 puzzle Ruud posted on www.sudocue.net/special.php July 13, 2007. My reformatting allows you to write pencil marks. So if you haven’t solved it yet you may want to give it a try.

There are four versions:
BlackFriday.png (Clues have a light yellow background)
BlackFriday_cbg=gbc.png (Clues have the same background colour as the grid)
BlackFriday_withPencilMarks.png (With computer generated pencil marks and clues with a light yellow background)
BlackFriday_withPencilMarks_cbg=gbc.png (With computer generated pencil marks and clues with the same background colour as the grid)

I will delete the files in a couple of days!!!

Why did you delete these sooo soon??? I was just about to tackle this and
it's gone! AAAGGGGGG.....

Is it possible to repost them for a week?

I can of course repost them, but it is easier for me to e-mail them to you, so please send me your e-mail address per PM or e-mail.

Cheers
Børge

lynn893 wrote:

Børge wrote:While we are waiting for Clueless Explosion 86 I have taken the liberty of reformatting the Black Friday gattai-21 puzzle Ruud posted on www.sudocue.net/special.php July 13, 2007.

Why did you delete these sooo soon??? I was just about to tackle this and
it's gone! AAAGGGGGG.....?

I made a readable version a long time ago and posted it on my "Ruud's specialty puzzles" thread:

A printable version can be found here that is easier on the eyes as well as on the print cartridge. (Click on "here" in the previous sentence.)