The New Sudoku Players' Forum

[winmine2]

I'm a newbie - sudoku has just started appearing in my local newpaper - NY Newsday. The very first puzzle (07/25/2005) published appears to have more than one solution? Can someone verify and let me know if i'm just making a newbie mistake? Thanks!

Original Puzzle

Code: Select all

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


Solution printed in newspaper (next day)

Code: Select all

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


My solution

Code: Select all

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


Thanks for any comments / corrections...

[/code]

[angusj]

Can someone verify and let me know if i'm just making a newbie mistake?

Hi winmine2.

Well, it looks like someone made a mistake, are you sure you copied it correctly? The puzzle you posted is slightly asymmetrical, so if you move the 4 at (3,1) to (2,1) as shown below the puzzle completes with a single solution.

Code: Select all

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

[winmine2]

thanks angusj,
I will check to see if I've entered the correct input puzzle (when i get to work tomorrow)- but, the rules at http://sudoku.com/rule.htm say that Every puzzle has just one correct solution". Either the statment is incorrect, or the puzzle is invalid? (can a puzzle be invalid?) thoughts?

[ArchieB]

If you check the solution quoted from the paper, then you will see that, as angusj says, there should be a 4 at 3,1 rather than 2,1. It's really down to whether the error was in the paper or in the copying!