The New Sudoku Players' Forum

[luvsudoku]

Hi,

Any pointers to websites/papers which describe the algorithms for creating (not solving) Sudoku puzzles? Like how to come up with the original pattern, and follow from there?

Thanks,
Mel

[Wolfgang]

If you mean handmade, see here
If you mean computer generated, there are a lot of possibilities, eg you can start with an empty sudoku or a full grid. Its easy to generate easy sudokus, more difficult to create hard ones and most difficult to create really good ones

[luvsudoku]

I'd like to understand the algorithms used to create them. I did see that
site you pointed to...but it started with an assumption of a pattern and didn't describe how to come up with the pattern. I see a lot of university projects on writing programs to create them, and I was curious if anything had been published (I am long past the university stage, no, this isn't for homework) This is for my own education and enjoyment. I've gotten pretty good at solving them, and wanted to see if I could learn how they are created.

[ab]

...and didn't describe how to come up with the pattern.

You choose the pattern you want to try.
If you start with a symmetrical pattern with 28 or 30 clues, you'll have a good chance of creating a puzzle. I've tried it myself twice and came up with a puzzle each time. Each time there was one point where I placed a number that led to a contradiction and had to backtrack a little. The site Wolfgang refers to doesn't mention that, but it does happen. Otherwise that link is really excellent.

[deam3r]

...and didn't describe how to come up with the pattern.

You choose the pattern you want to try.
If you start with a symmetrical pattern with 28 or 30 clues, you'll have a good chance of creating a puzzle. I've tried it myself twice and came up with a puzzle each time. Each time there was one point where I placed a number that led to a contradiction and had to backtrack a little. The site Wolfgang refers to doesn't mention that, but it does happen. Otherwise that link is really excellent.

Agree, I am a SuDoKu player and fan adn I agree with Ab.