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

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

Posts: 3
Joined: 14 January 2006

It's always handy to post the list of candidates as well, if you're using them, so we can tell what eliminations you've already made
Code: Select all
*-----------------------------------------------------------*
| 37    12    5     | 8     279   29    | 6     4     1379  |
| 37    9     4     | 27    6     1     | 8     235   357   |
| 6     128   18    | 4     3     5     | 27    29    179   |
|-------------------+-------------------+-------------------|
| 1     5     6     | 9     27    3     | 27    8     4     |
| 89    4     89    | 27    1     6     | 2357  235   357   |
| 2     3     7     | 5     8     4     | 9     1     6     |
|-------------------+-------------------+-------------------|
| 359   7     39    | 1     4     8     | 35    6     2     |
| 3589  18    1389  | 6     259   29    | 4     7     359   |
| 4     6     2     | 3     59    7     | 1     59    8     |
*-----------------------------------------------------------*

• You have a naked pair of 3 and 7 in column 1 so can remove any other 3s and 7s from that column (and from box 1 as well seeing as they're in the same box)
• You have locked candidates of 7 in row 3 - the only place they can go is in box 3, so any other 7s in box 3 that are not in that row can be removed
• ditto for 9s in row 3 and also row 7
• another naked pair of 2 and 7 in column 7
• an x-wing on 2s in rows 2 and 5 - the only place a 2 can go in either of those rows is in columns 4 and 8, so you can remove any other 2s in those columns that aren't in those rows
This leads you to your next placement and you can easily solve the puzzle from there.

here or here
Shazbot

Posts: 220
Joined: 24 September 2005

*---------------------------------------------------------*
| 37 12 5 | 8 279 29 | 6 4 13 |
| 37 9 4 | 27 6 1 | 8 235 35 |
| 6 128 18 | 4 3 5 | 27 29 179 |
|-------------------+-------------------+----------------|
| 1 5 6 | 9 27 3 | 27 8 4 |
| 89 4 89 | 27 1 6 | 35 235 357 |
| 2 3 7 | 5 8 4 | 9 1 6 |
|-------------------+-------------------+---------------|
| 59 7 39 | 1 4 8 | 35 6 2 |
| 58 18 138 | 6 259 29 | 4 7 359 |
| 4 6 2 | 3 59 7 | 1 59 8 |
*-----------------------------------------------------------*

Thanks for your response. I should have included the candidates in my original post as I have here. As I understand your previous actions, I would have ended at the above position and I'm still stuck.
jaycarr

Posts: 3
Joined: 14 January 2006

Shazbot wrote:an x-wing on 2s in rows 2 and 5

allows you to remove the 2 from r3c8.

Code: Select all
*--------------------------------------------------*
| 37   12   5    | 8    279  29   | 6    4    13   |
| 37   9    4    | 27*  6    1    | 8    235* 35   |
| 6    128  18   | 4    3    5    | 27   29   179  |
|----------------+----------------+----------------|
| 1    5    6    | 9    27   3    | 27   8    4    |
| 89   4    89   | 27*  1    6    | 35   235* 357  |
| 2    3    7    | 5    8    4    | 9    1    6    |
|----------------+----------------+----------------|
| 59   7    39   | 1    4    8    | 35   6    2    |
| 58   18   138  | 6    259  29   | 4    7    359  |
| 4    6    2    | 3    59   7    | 1    59   8    |
*--------------------------------------------------*

If you're interested in posting the grid with the columns lined up you can

1. do it manually then highlight it and click code or

2. download Simple Sudoku from this site http://angusj.com/sudoku/index.php Then you can enter the original clues into SS, which will insert all the candidates automatically, then copy & paste that grid into your post as seen here.
sweetbix

Posts: 58
Joined: 10 December 2005

I would go with doing it manually.

Copying the clues in a helper/solver and then pasting it here with the pencilmarks is not a great idea. Either the helper removes all the obvious pencilmarks, in which case elimenations where made that the person missed, or with all the pencimarks meaning that it is impossible to tell what techniques were succesfully applied. (and this also requires a reply to cover all the basic elimneations... which might be a bit silly).

(As far as formatting goes: did you read: New topics - How to ask for help? It lists a small proceude on how to post a puzzle using code-tags.)
Animator

Posts: 469
Joined: 08 April 2005