The New Sudoku Players' Forum

[tanja]

can you help me to solve this sudoku?

3 _ 2._ _ 1.9 _ _.
_ _ 1._ _ _._ _ _.
_ 6 _._ _ _.1 _ _.
.........................
9 _ _._ 2 5._ _ _.
8 _ _._ 4 _._ 1 9.
_ 3 6._ _ _._ 4 5.
.........................
_ _ _._ _ _._ 9 1.
4 _ _._ _ _._ _ 8.
_ _ _.7 _ 2.5 _ _.

all the help is welcome!

[tso]

Your puzzle is invalid. It has muliple solutions.

[Cec]

"...all the help is welcome!

Hi tanja,

Not sure whether you know what "multiple solutions" means. Members are welcome to correct my following explanations if incorrect.

Tanya, you didn't indicate how far you progressed so I'll assume you got this far with basic solving techniques:

Code: Select all

 *-----------*
 |342|..1|9..|
 |..1|...|4..|
 |.6.|...|1..|
 |---+---+---|
 |914|825|...|
 |8..|.4.|219|
 |236|...|845|
 |---+---+---|
 |62.|...|.91|
 |4..|...|.28|
 |1..|7.2|5.4|
 *-----------*


Your "candidate" (or "pencilmark") grid would now look like this.

Code: Select all

 
 *-----------------------------------------------------------------------------*
 | 3       4       2       | 56      5678    1       | 9       5678    67      |
 | 57      89      1       | 23569   356789  36789   | 4       35678   2367    |
 | 57      6       89      | 23459   35789   34789   | 1       3578    237     |
 |-------------------------+-------------------------+-------------------------|
 | 9       1       4       | 8       2       5       | 36      367     367     |
 | 8       57      57      | 36      4       36      | 2       1       9       |
 | 2       3       6       | 19      179     79      | 8       4       5       |
 |-------------------------+-------------------------+-------------------------|
 | 6       2       3578    | 345     358     348     | 37      9       1       |
 | 4       57      3579    | 13569   13569   369     | 367     2       8       |
 | 1       89      389     | 7       3689    2       | 5       36      4       |
 *-----------------------------------------------------------------------------*


Because there are no further logical solving techniques to eliminate further candidates, the option of guessing will lead to more than one solution which means the puzzle is invalid.

All puzzles produced by Pappocom are valid meaning there is only one unique solution.

Hope this helps.

Cec

[JPF]

To illustrate what "multiple solutions" means , here are for example 2 different grids matching your initial puzzle :

Code: Select all

 3 4 2 | 5 7 1 | 9 8 6
 7 9 1 | 2 8 6 | 4 5 3
 5 6 8 | 9 3 4 | 1 7 2
-------+-------+-------
 9 1 4 | 8 2 5 | 3 6 7
 8 5 7 | 6 4 3 | 2 1 9
 2 3 6 | 1 9 7 | 8 4 5
-------+-------+-------
 6 2 3 | 4 5 8 | 7 9 1
 4 7 5 | 3 1 9 | 6 2 8
 1 8 9 | 7 6 2 | 5 3 4



Code: Select all

 3 4 2 | 5 7 1 | 9 8 6
 5 8 1 | 2 6 9 | 4 3 7
 7 6 9 | 3 8 4 | 1 5 2
-------+-------+-------
 9 1 4 | 8 2 5 | 6 7 3
 8 5 7 | 6 4 3 | 2 1 9
 2 3 6 | 9 1 7 | 8 4 5
-------+-------+-------
 6 2 3 | 4 5 8 | 7 9 1
 4 7 5 | 1 9 6 | 3 2 8
 1 9 8 | 7 3 2 | 5 6 4



Your puzzle has 344 solutions.

JPF

[tanja]

Dear JPF and Cec,

Thank you so much for helping me solve this sudoku,

I had no idea there where 344 solutions, when I couldn’t fine one.
I’m a level 2 player and this was a level 4 sudoku..
But now I have two answers:
914825367 and 914825673
And finished my first sudoku book!
I will look up al the tips , thank you so much.

[tanja]

o dear.......
I wanted to fill him in in my sudoku book and saw I missed a cijfer, I'm so sorry..... can you help me again.
*-----------*
|342|..1|9..|
|. .1|.. .|4..|
|. 6.|.. .|1..|
|---+---+---|
|914|825|...|
|8.5|.4.|219|
|236|...|845|
|---+---+---|
|62.|...|.91|
|4..|...|.28|
|1..|7.2|5.4|
*-----------*

maybe now there is only one solution?

[ravel]

No, still multiple solutions (183).

If your book is not "Sudoku ?" published by Hinkler Books, Pty Ltd., please add to to the Sudokus of Shame list.

[Cec]

"...maybe now there is only one solution?"

Sorry tanja but this puzzle will always have more than one solution which makes it an invalid puzzle. JPF merely posted two different grids to show how this can occur.

I know it's disappointing but I would suggest you discard this puzzle and replace it with a genuine puzzle having one unique solution such as a Pappocom puzzle.

Cec

[ravel]

Maybe you can take comfort in this (level 2 ?) puzzle (you know hidden pairs?). It has

Code: Select all

 +-------+-------+-------+
 | . . . | . 4 2 | 6 5 . |
 | . . . | 6 5 . | 1 4 . |
 | . . 4 | 7 . 9 | . 8 . |
 +-------+-------+-------+
 | . 3 7 | . . 4 | 9 1 . |
 | . 9 . | . . 6 | . 3 . |
 | . . . | . . 8 | 2 7 . |
 +-------+-------+-------+
 | . . . | . . 5 | . 9 . |
 | . . . | . . 1 | 4 6 . |
 | . . . | . 9 7 | . 2 3 |
 +-------+-------+-------+


solution.

[udosuk]

ravel, Simple Sudoku used a naked quad instead of the hidden pair/triple to solve yours... Are you sure it isn't too hard for level 2? (But it doesn't need any locked candidates moves... I wonder for pen & paper players whether naked/hidden pairs or locked candidates are more difficult to spot...)

[JPF]

This one is LEVEL :

Code: Select all

 . . . . 8 3 2 5 .
 . . . 5 1 2 4 9 .
 . . 8 7 . 4 3 6 .
 . 2 3 . . 7 9 8 .
 . . . . . 5 6 2 .
 . . . . . 8 1 7 .
 . . . . . 9 5 1 .
 . . . . . 6 8 3 .
 . . . 8 3 1 7 4 6



JPF

[ravel]

ravel, Simple Sudoku used a naked quad instead of the hidden pair/triple to solve yours... Are you sure it isn't too hard for level 2? (But it doesn't need any locked candidates moves... I wonder for pen & paper players whether naked/hidden pairs or locked candidates are more difficult to spot...)

Without pencilmarks hidden pairs are easier to spot than naked pairs/triples etc. But normally locked candidates are still easier. Think you are right, that level 2 probably is locked candidates. So lets take this one:

Code: Select all

 . . . . 6 5 2 7 .
 . . . 2 1 . 8 6 .
 . . 4 7 . 9 . 5 .
 . 7 9 . . 1 4 8 .
 . 6 . . . 2 . 9 .
 . . . . . 8 5 1 .
 . . . . . 6 . 4 .
 . . . . . 7 6 3 .
 . . . . 9 4 . 2 8


[tanja]

hi every one, I had the final sudoku from my book done and start soon on a new book. thank you for everything