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

x x 2 3 9 7 x x x
3 x x x 5 8 x 1 x
x x x x x x 9 x x
6 2 x x 3 9 1 x x
x x x x x x x x x
8 x 3 2 7 x x 6 9
x 3 5 7 8 6 x x x
x 8 x 5 1 x x x 6
x x x 9 x 3 8 x x

Where do I go from here. I have found some hidden doubles, but it does not seem to help.

Thanks

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franksg

Posts: 2
Joined: 28 January 2008

franksq,

Where does the 5 have to go in row 4? Can 5 candidates be removed from block 6?

dan
dan

ArkieTech

Posts: 2866
Joined: 29 May 2006
Location: NW Arkansas USA

Hi franksg,

I hope my comments are accepted as being constructive.

Your request for help highlights the dilemma I have from time to time in trying to decide the extent of help without the benefits of a crystal ball as to how much a "newcomer" understands about sudoku.

franksg, if you haven't yet read the forum's recommended steps for posting puzzles and terminology then click on the following links:

http://forum.enjoysudoku.com/viewtopic.php?p=17121#p17121
http://forum.enjoysudoku.com/viewtopic.php?t=4120

Note the nine 3X3 grids are called "Boxes" or "Blocks" as preferred by some members.

There are numerous links throughout the forum describing various solving techniques ranging from Basic to Advanced . These include the following basic solving techniques:

http://www.angusj.com/sudoku/hints.php

When requesting help, the above recommended steps for posting puzzles will produce the following grids which you will see are easier to read:
Code: Select all
` *-----------* |..2|397|...| |3..|.58|.1.| |...|...|9..| |---+---+---| |62.|.39|1..| |...|...|...| |8.3|27.|.69| |---+---+---| |.35|786|...| |.8.|51.|..6| |...|9.3|8..| *-----------*  *-----------------------------------------------------------------------------* | 145     1456    2       | 3       9       7       | 456     458     458     | | 3       4679    4679    | 46      5       8       | 2467    1       247     | | 1457    14567   14678   | 146     246     124     | 9       234578  234578  | |-------------------------+-------------------------+-------------------------| | 6       2       47      | 48      3       9       | 1       4578    4578    | | 14579   14579   1479    | 1468    46      145     | 23457   234578  234578  | | 8       145     3       | 2       7       145     | 45      6       9       | |-------------------------+-------------------------+-------------------------| | 1249    3       5       | 7       8       6       | 24      249     124     | | 2479    8       479     | 5       1       24      | 2347    23479   6       | | 1247    1467    1467    | 9       24      3       | 8       2457    12457   | *-----------------------------------------------------------------------------*`

Now, following on from ArkieTech's above hint, you'll see that in Box 6, there are two candidate 5's which are "Locked" into row 4 which means the remaining candidate 5's in that Box can be excluded. This technique is known as "Locked Candidates" and is more fully explained in the above solving technique links.

Another hint is a "hidden single" in column 3 which restricts a particular candidate to only one cell in that group which thus solves that cell.

That's enough homework for one day and good luck with your sudoku solving.

Edited by Cec 2.50pm

Cec
Cec

Posts: 1039
Joined: 16 June 2005