dailysudoku.com

[kathyjc]

Hi,

Just need some help with the logic for this puzzle. This is where I have reached.


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

9 * * | 1 * * | 4 7 *
3 1 * | * * * | * 9 8
* 4 7 | * * 9 | 3 * 1

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

The hint feature places a 2 in the 4th row, 3rd col... but I am not sure why. And even when I take that hint I do not get much further before being stuck again. Any assistance with the logic would be appreciated.

[TKiel]

Kathjc,

Here is the grid with pencilmarks:

[David]

Hi Kathy

I think you will find the key to this puzzle is an 'X-wing' on 6's.
If you look at column4 there are only two cells which can hold a 6 (row6,9). Similarly on column8 there are only two cells for a 6 (rows 6,9) again. So you can eliminate the 6 from c1r6 (making it an 8) and the whole puzzle collapses from here

[gigi]

I know there are many ways to solve the puzzle, but I was able to solve it without any of the advanced techniques (x-wings, etc). I didn't even have put in pencil marks until almost the end... and I'm a pencil mark user all of the time. I'm not sure why this was classified as a very hard??? Oh well... have a great long weekend, if you are lucky enough to be off!...

Laterz... gigi

[David Bryant]

[Bill Denholm]

I usually use the traditional techniques, too, but I couldn't have solved this puzzle withoout the X-Wings.

Bill

[kathyjc]

Thanks for the help. The "X-wings" clue helped a lot. I never looked for that before.