The New Sudoku Players' Forum

[Joulies]

Hello. I am having serious problem with a sudoku table. I have been trying to solve it for like two days and I mean that. I even downloaded a solver, something that I've never done to any other table before. But this one really looks bizzare to me.
Yes I have the solution but I want to see a hint to that point I am stuck. I present you the table to its original shape and up to the point I managed to solve it.

|7 _ _|_ 9 _|_ _ 2| * * * * * |7 _ _|4 9 _|_ 1 2|
|_ _ _|6 _ 1|_ _ _| * * * * * |_ _ _|6 7 1|_ _ _|
|_ _ 1|3 _ _|6 7 _| * * * * * |_ _ 1|3 _ _|6 7 _|

|_ _ _|_ 6 _|_ 9 _| * * * * * |_ 7 _|_ 6 _|_ 9 _|
|6 _ _|7 _ 4|_ _ 3| * * * * * |6 _ _|7 _ 4|_ 2 3|
|_ 8 _|_ 1 _|_ _ _| * * * * * |_ 8 _|9 1 _|_ 6 7|

|_ 4 7|_ _ 9|2 _ _| * * * * * |_ 4 7|1 _ 9|2 _ 6|
|_ _ _|5 _ 7|_ _ _| * * * * * |_ _ _|5 _ 7|_ _ _|
|3 _ _|_ 4 _|_ _ 1| * * * * * |3 _ _|_ 4 6|7 _ 1|

I know that the second table is correct. But I really want you to give me a hint on how to continue.
Thanx
A sudoku crazy fella from Greece

[tarek]

If this is your regular sudoku, then I'm afraid it has multiple solutions....

The reason why is that you can interchange freely Columns 4,5,6 & still have a valid solution....

tarek

[ravel]

You can solve it with an xwing for number 9 in rows 5,9/cols 2,3, which allows you to eliminate 9 from r3c2.

Tarek, in every unique puzzle you can interchange the columns of a stack to get a unique solution - it is a different, but equivalent puzzle then.

[tarek]

I must be missing something here ravel, what is a sudoku table?

Is it some kind of variant?

what I can see are 3 puzzles, all have columns 4,5,6 empty...... if this is a regular "vanilla" sudoku, you can't reach a solution using x-wing. The only way is through guessing or using the 1-solution based logic.

Tarek

[TKiel]

I think the sort of candidate grid thing on the left are the initial clues:

Code: Select all

|7 _ _|_ 9 _|_ _ 2|
|_ _ _|6 _ 1|_ _ _|
|_ _ 1|3 _ _|6 7 _|

|_ _ _|_ 6 _|_ 9 _|
|6 _ _|7 _ 4|_ _ 3 
|_ 8 _|_ 1 _|_ _ _| 

|_ 4 7|_ _ 9|2 _ _|   
|_ _ _|5 _ 7|_ _ _| 
|3 _ _|_ 4 _|_ _ 1|   


And the thing on the right is the point to which it has been solved:

Code: Select all

|7 _ _|4 9 _|_ 1 2|   
|_ _ _|6 _ 1|_ _ _|
|_ _ 1|3 _ _|6 7 _| 

|_ 7 _|_ 6 _|_ 9 _|
|6 _ _|7 _ 4|_ 2 3|
|_ 8 _|9 1 _|_ 6 7|

|_ 4 7|1 _ 9|2 _ 6|
|_ _ _|5 _ 7|_ _ _|
|3 _ _|_ 4 6|7 _ 1|


I entered it into SS and it only has one solution.

Tracy

(Edited to make second grid same as original post. My apologies.)

[tarek]

Ah... I see it now, This is a first one....

Thanx for confusing me Joulies, I hope that next time the puzzle is posted using the standard format.......

Tarek

[Tumbleweed]

You can solve it with an xwing for number 9 in rows 5,9/cols 2,3, which allows you to eliminate 9 from r3c2.

Tarek, in every unique puzzle you can interchange the columns of a stack to get a unique solution - it is a different, but equivalent puzzle then.

Isnt a simpler option to observe that the only place 4 can go in column 4 is in row 1? Unless I have copied it down wrongly? (this is in the 'solved as far as I can go' second table)

Tw

[TKiel]

Tumbleweed,

If you used my post as the source, the grid was not the same as in the original post, for which I apologize. I must have deleted a couple of numbers by mistake. My post above has been edited to reflect the grid as it is shown in the first post in this thread.

Tracy

[tso]

Code: Select all

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


The 9 in box 9 MUST be in row 8.
Therefore, the 9 in column one MUST be in box 1.
Therefore, r3c2<>9.

The 2 in box 2 MUST be in row 3.
Therefore, r3c2<>2.

That leaves 5 as the only digit left that can go in r3c2.

It should be easy after that.