The New Sudoku Players' Forum

[nadav3]

hello
I'm learning advanced techniques to solving sudoko puzzles.
I'm stuck with this one, I've tried anything I know (hidden singles, naked pairs, triples and quads, x-wing) and still cannot find the next move.
can someone enlighten me?
the pencil marks shown are after I narrowed down the options.
thank you

[JasonLion]

I see a locked candidate on 5 in row 6, and then singles to the end.

[Pat]

(5) b1\c2
solves the 5 for r6

[nadav3]

thanks a lot... don't know how I didn't see it...
Pat, what does this mean in words: (5) b1\c2 ?

[JasonLion]

Pat was pointing out a different locked candidate, digit 5 in block 1 which eliminates 5s in the rest of column 2, and also solves the puzzle with singles to the end.

[nadav3]

thanks, I don't understand how I missed that...

[Pat]

1. box\line: (5) b1\c2 --> r6 5
2. line\box: (5) c3\b4 --> r6 5
3. line\box: (5) r6\b4 --> c3 5 [ path suggested by JasonLion ]
   
   the symmetry between b and c
   makes me reluctant to prefer one over the other,
   so how about going to a fish of order 2:
   
   
4. X-wing: (5) r6c3\b44 --> b4 5
   [ one of those bizzare beasts with same house twice in the cover ]