dailysudoku.com

[Jared]

I have been doing sudoku quite a while. I have never started one that I could not finish, however this is the first time I have finished with multiple solutions. Did anybody else have the same experiece

[Jared]

[David Bryant]

Hi, Jared! Nice to hear from you.

I worked this puzzle yesterday with a pen and paper, and just verified the logic again today with my PC. I'm certain this puzzle (23 Jan 2006 "Classic") has a unique solution.

Could you post your two solutions so we can take a look at them? Most likely you left a digit out when you copied the puzzle, or something like that. dcb

[Jared]

what I have ended Like This:

175 489 326
843 162 975
692 735 418

536 274 189
781 596 234
924 _1_ 657

259 _4_ 761
467 621 893
318 957 542

It seems to me that the 3 and the 8 missing can be interchanged creating two solutions. I am probably wrong somewhere though. let me know what you come up with

[Jared]

I just found my mistake! That sure isn't good for my self esteem!

[alanr555]

--- --- ---
843 --- ---
--- --- ---

--- 2-- 189
-81 5-6 -34
92- _1_ ---

--9 _-_ --1
4-- --- 89-
-1- --- 5--


The above placements are incorrect.
Being 23 of them, correction is not trivial.

Is there ANY alternative to starting again?

I have sometimes "caught" an error within a fairly short timescale
and been able to work out (after a lengthy review!) a correction
that retrieved the situation but in over 80% of cases an error has
led to abandonment and a restart.

Of course, there is a whole psychology as to when the errors occur.
One does need to be in the right frame of mind.

Mentioning that, has anyone any hints as to how to RESUME a
puzzle after an interruption? It seems so easy to lose track of
how far one had got and it takes time to retrieve a familiarity
with the puzzle. Is this just a question of training the short-term
memory to be able to cope with say half-hour interruptions?

Alan Rayner BS23 2QT