algorithm for the last few please

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algorithm for the last few please

Postby quyet1990 » Wed Jan 28, 2015 11:01 am

can somebody please give me an algorithm that will help me to fill in the last few here. I can solve it using a guess and check, but would prefer to have an algorithm. Thanks in advance
Thank jeffcia. My english is very bad.

There is a Sudoku board I would like you to look at

Click on this link:
http://www.sudokuwiki.org/sudoku.htm?bd=127539864459286700368100259913452678675008402842600590586000127294761385731825946

This is a text version of the board useful for posting on forums:
Code: Select all
+--------------+--------------+--------------+
|    1   2   7 |    5   3   9 |    8   6   4 |
|    4   5   9 |    2   8   6 |    7  13  13 |
|    3   6   8 |    1  47  47 |    2   5   9 |
+--------------+--------------+--------------+
|    9   1   3 |    4   5   2 |    6   7   8 |
|    6   7   5 |   39  19   8 |    4  13   2 |
|    8   4   2 |    6  17  37 |    5   9  13 |
+--------------+--------------+--------------+
|    5   8   6 |   39  49  34 |    1   2   7 |
|    2   9   4 |    7   6   1 |    3   8   5 |
|    7   3   1 |    8   2   5 |    9   4   6 |
+--------------+--------------+--------------+
Last edited by quyet1990 on Thu Jan 29, 2015 4:16 pm, edited 1 time in total.
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Re: algorithm for the last few please

Postby JasonLion » Wed Jan 28, 2015 6:15 pm

That puzzle has multiple solutions. I don't believe any further progress is possible without randomly picking one of the solutions.
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Re: algorithm for the last few please

Postby Leren » Wed Jan 28, 2015 8:06 pm

According to your link this is the original puzzle on Andrew Stuart's Sudoku site:

Code: Select all
...1.5...
14....67.
.8...24..
.63.7..1.
9.......3
.1..9.52.
..72...8.
.26....35
...4.9...

and this is the solution

Code: Select all
672145398
145983672
389762451
263574819
958621743
714398526
597236184

It looks to me like your link refers to the wrong puzzle. In that case you would have to change your link or write out the original puzzle manually'.

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Re: algorithm for the last few please

Postby quyet1990 » Thu Jan 29, 2015 4:15 pm

http://www.sudokuwiki.org/sudoku.htm?bd=127539864459286700368100259913452678675008402842600590586000127294761385731825946

Because, the link I posted is not complete, it will be something else. This is the soduku that I want solve.
Code: Select all
+--------------+--------------+--------------+
|    1   2   7 |    5   3   9 |    8   6   4 |
|    4   5   9 |    2   8   6 |    7  13  13 |
|    3   6   8 |    1  47  47 |    2   5   9 |
+--------------+--------------+--------------+
|    9   1   3 |    4   5   2 |    6   7   8 |
|    6   7   5 |   39  19   8 |    4  13   2 |
|    8   4   2 |    6  17  37 |    5   9  13 |
+--------------+--------------+--------------+
|    5   8   6 |   39  49  34 |    1   2   7 |
|    2   9   4 |    7   6   1 |    3   8   5 |
|    7   3   1 |    8   2   5 |    9   4   6 |
+--------------+--------------+--------------+
quyet1990
 
Posts: 3
Joined: 28 January 2015

Re: algorithm for the last few please

Postby JasonLion » Thu Jan 29, 2015 10:07 pm

As before, this puzzle has two solutions. You can not proceed further with logic alone since logic provides no way to choose between the two solutions.
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Re: algorithm for the last few please

Postby Leren » Fri Jan 30, 2015 12:12 am

Your amended link comes up on Andrew Stewart's site with the puzzle as you describe. If you click on the Solution Count button it will show you that it has 2 solutions.

They are :

127539864
459286713
368147259
913452678
675918432
842673591
586394127
294761385
731825946

and

127539864
459286731
368174259
913452678
675398412
842617593
586943127
294761385
731825946

The puzzle has so many clues it is hard to believe that it was an original puzzle - it looks like a puzzle that was partially solved but has a mistake somewhere. Maybe Andrew posted an invalid puzzle.

Leren
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Re: algorithm for the last few please

Postby quyet1990 » Fri Jan 30, 2015 3:16 am

Thank Leren very much. I understand their problems encountered
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Posts: 3
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