Soduku (Sudoku) is a Japanese number puzzle game that seems to be taking the world by storm. It’s played on a 9×9 grid. Each square can contain one of the numbers from 1 to 9 (inclusive). A given “problem” has some of the squares filled in, and you are required to fill in the remaining squares, satisfying the constraints:

- Each row has to contain each of the numbers 1 through 9 exactly once.
- Likewise for each column.
- The board can be broken down into 9 3×3 squares (top-left, top-middle, top-right, etc.). Each of these has to contain each of the numbers 1 through 9 exactly once.

Anyway, these puzzles can get pretty tricky. Especially if you don’t know the third rule above — which until recently, I didn’t. Anyway, they’ve sufficient annoyed me now that I had to do something about it; so I wrote

**The Langabi.name Soduku Solver**

It’s not fancy, but is (in my opinion) very efficient. Enjoy!

**Edit:** Now available: an explanation of the method my solver uses, and the source code.

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Sure! I’m pleased it helped you scam your maths class!

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Hmm… I tried with a super hard soduku and the results just came out and here i am cracking my brains to solve it.

😉

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200308007

100000005

400759006

809000504

020000083

304080709

902845001

500000002

000102058

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plese help me find this i have been tring to find this onefor 2 weeks

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Hi Alyssa,

You can just put the problem into my solver, following the link at the top of the page, and it’ll solve it for you. I actually just did so, and got:

2 5 6 3 1 8 4 9 7

1 9 7 6 2 4 8 3 5

4 3 8 7 5 9 2 1 6

8 7 9 2 3 1 5 6 4

6 2 5 4 9 7 1 8 3

3 1 4 5 8 6 7 2 9

9 6 2 8 4 5 3 7 1

5 8 1 9 7 3 6 4 2

7 4 3 1 6 2 9 5 8

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I have a little Neopets help site and Neopets created the game Roodoku which is their version of Sudoku. I was hoping to find a free script that I could host myself for my visitors to use to solve the puzzles for them. I found the source code to this, but I’m not a programmer and can’t get it to work. 😦

I’ve seen the online version though, and it’s a blessing!

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This puzzle won’t solve because it times out with Firefox. Any suggestions?

–9 –6 4–

–3 — -7-

-2- -8- —

1– 5– –6

-8- 2– -3-

7– — –9

— -4- -8-

-5- — 1–

–6 9– 2–

Thanks,

Bob E

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Unfortunately, there seem to be a few puzzles for which my algorithm is not ideal — in technical terms, it needs to do the “bound” part of the branch and bound algorithm sooner. I’ve thought of a few ways to achieve this … and then ran out of energy. Sorry. But it works for nearly all other puzzles.

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Why when I enter my numbers and hit solve, does it timeout?

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See above comment.

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I test this.Great.

2

177

5******3*84****15

6

9*****

286419*****8

****41**6

******9

116****47

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Any idea where I can find an efficient java source code for soduko?

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Nope, sorry — you could of course re-code mine, but it’s actually not very efficient in its current form, it prunes the branches a little late.

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…quick question not related to the sudoku but rather to php, are there any php video tutorials/awesome php books that you may recommend to someone who’s good at programming in java?

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Cud u pls give the source code of the Sudoku game & the Sudoku solver in Java

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Cud u pls give the source code of the Sudoku game & the Sudoku solver in Java

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There’s a link at the bottom of the post to the source code in PHP. Translation to Java should be easy enough!

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Hi

I’ve found another run timeout error

on the f_1_1_1 put value=2

then f_8_9_9 put value=2 too

It leads me to error.. would you explain or fix it?

Thanks

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Not working as it did before

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