The New Sudoku Players' Forum

[Jackie78]

Hi,

I am currently having trouble with this sudoku, which I have solved so far, but simply cannot find the next logical step without having to guess. Can you please help?

Code: Select all

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


The Original one I found here: http://sudoku.zeit.de/sudoku/kunden/die_zeit/pdf/sudoku_2008-03-06_schwer.pdf

Thanks for your help

[StrmCkr]

where are you stuck on this puzzle.?

that would help.

candidates grid.

like this.

Code: Select all

 *--------------------------------------------------------------------*
 | 1589   13589  1356   | 4      2      39     | 19     68     7      |
 | 49     7      2      | 1      8      6      | 5      3      49     |
 | 1489   1389   1346   | 7      5      39     | 149    2      14689  |
 |----------------------+----------------------+----------------------|
 | 1589   1589   15     | 6      4      2      | 3      7      19     |
 | 2      39     34     | 5      7      1      | 8      46     469    |
 | 14     6      7      | 9      3      8      | 14     5      2      |
 |----------------------+----------------------+----------------------|
 | 7      15     15     | 8      6      4      | 2      9      3      |
 | 6      2      9      | 3      1      5      | 7      48     48     |
 | 3      4      8      | 2      9      7      | 6      1      5      |
 *--------------------------------------------------------------------*


theres a pointing pair on column 3 (1&5)
removes 1&5 from R1,3C3

theres a Hidden pair in box 3 (8/6)
wich exposes a locked candidate 1 (R1C7 &R3C7) in box 3 forces
r6c7 = 4

puzzles reduces to singles at this point.

[Pat]

I am currently having trouble with this sudoku, which I have solved so far, but simply cannot find the next logical step

Code: Select all

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



The original one I found here: http://sudoku.zeit.de/sudoku/kunden/die_zeit/pdf/sudoku_2008-03-06_schwer.pdf

hi Jackie78,

in box 6,
the 9 is in column 9
-- exclude 9 elsewhere in that column

[Cec]

Hi Jackie78,

There are a number of links which explain the basic solving techniques such as "Locked Candidates" (1) and (2) (also known as "Pointing Pairs"), "Singles", "Naked Pairs", "Triples", etc. You could try these...

http://www.angusj.com/sudoku/hints.php
http://www.sadmansoftware.com/sudoku/techniques.htm
http://www.scanraid.com/BasicStrategies.htm

The procedure for posting puzzles, including the Pencilmark Grid, is described Here

Happy sudoku solving

Cec