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Every Sudoku has one solution... I found two...

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benst
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Every Sudoku has one solution... I found two...

Every Sudoku has one solution, or? (Wikipedia)
But I found two.
Look on:
Image1
Image2
Save1 (sudoku.prefs)
Save2
Is it a bug or did I a mistake?

Ben

John T. Haller
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Depend on definition

Impossible is designed to have multiple solutions (you simply *have* to guess). Sometimes on Hard mode, there will be two solutions. It's the way the algorithm works. Since this generates an unlimited number (as opposed to most free - and some paid - sudoku games which only include a few dozen pre-built puzzles) and doesn't have a solver built-in, this happens occasionally. There is a debate on the development site as to whether this is a big deal (do sudokus *have* to have only one solution, or is it considered *ideal* for them to but not necessary?). You can follow this discussion here:
http://www.fltk.org/str.php?L1361+P0+S0+C0+I0+E0+Qsudoku

The "bug" was fixed in the subversion repository (code bank) by posting a notice that hard and impossible have multiple solutions, which is why they are hard and impossible. I'll be updating the portable version to this new update in the future. In the meantime, I've updated the product page with this information.

Sometimes, the impossible can become possible, if you're awesome!

R.
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Medium too!

Well, "Medium" mode (my personal level ;-)), too, often has more than 1 solution. Never thought this could be a problem for anyone. I don't see how several solutions could impair someone's fun of playing the game. Actually, I find, it adds to the fun when I come across a few numbers which I suspect to be some of those that can be interchanged and then see it confirmed afterwards.

splattymelt
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Multiple solutions...

according to wikipedia.com:
"the puzzle cannot be considered the first Sudoku because, under modern rules, it has two solutions" This is in reference to a puzzle written in 1892 by Le Siècle, a Paris-based daily newspaper. Therefore, two solutions means NOT a SuDoKu. That is why it is so infuriating to some of us...

reference:
http://en.wikipedia.org/wiki/Sudoku

John T. Haller
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The way it is

Like it or not, that's the way this version of Sudoku works. Right now, the choice is either help fix the code to work a better way (a couple people have started work on this) or stop using it.

So... for anyone else that missed it... this version of sudoku can have multiple solutions. That's the way it works. You can argue all you like about whether this is valid or invalid... but the arguments have no effect at all on the way the actual code works. The original author is happy with it as is. I'm just making it portable.

Sometimes, the impossible can become possible, if you're awesome!

Ryan McCue
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And

Removing the sound Wink
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R McCue
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And before anyone complains about the grammar, I'm so jetlagged that my
hands aren't even in the same time zone...

"If you're not part of the solution, you're part of the precipitate."

John T. Haller
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Try the original

You'll see why.

Sometimes, the impossible can become possible, if you're awesome!

Ryan McCue
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AAAHHHH!!!

So... Horrible.
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R McCue
PortaBlog Home and My Website
And before anyone complains about the grammar, I'm so jetlagged that my
hands aren't even in the same time zone...

"If you're not part of the solution, you're part of the precipitate."

IrishPrince
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Try Sudoku Sover online

John, you may want to check out Sudoku Solver by Andrew Stuart at: http://www.scanraid.com/sudoku.htm

He has the most advanced Javascript solver on the 'net. I don't know if he allows the use of his code, but if he does it will do all the checks and strategies that anyone could possibly want.

-IP

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