## algorithm for the last few please

Post the puzzle or solving technique that's causing you trouble and someone will help

### algorithm for the last few please

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

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.
quyet1990

Posts: 3
Joined: 28 January 2015

### Re: algorithm for the last few please

That puzzle has multiple solutions. I don't believe any further progress is possible without randomly picking one of the solutions.

JasonLion
2017 Supporter

Posts: 640
Joined: 25 October 2007
Location: Silver Spring, MD, USA

### Re: algorithm for the last few please

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
`672145398145983672389762451263574819958621743714398526597236184`

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'.

Leren
Leren

Posts: 3319
Joined: 03 June 2012

### Re: algorithm for the last few please

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

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.

JasonLion
2017 Supporter

Posts: 640
Joined: 25 October 2007
Location: Silver Spring, MD, USA

### Re: algorithm for the last few please

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
Leren

Posts: 3319
Joined: 03 June 2012

### Re: algorithm for the last few please

Thank Leren very much. I understand their problems encountered
quyet1990

Posts: 3
Joined: 28 January 2015