dailysudoku.com Forum Index dailysudoku.com
Discussion of Daily Sudoku puzzles
 
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

Cheating?

 
Post new topic   Reply to topic    dailysudoku.com Forum Index -> Solving techniques, and terminology
View previous topic :: View next topic  
Author Message
oaxen



Joined: 10 Jul 2006
Posts: 96

PostPosted: Thu Mar 12, 2009 4:35 pm    Post subject: Cheating? Reply with quote

Am I cheating - or why am I always successful solving advanced puzzles?
My method after all the basics:
Find two equal numbers in a row or a column, where they only are represented twice. Mostly there are more alternaties, but it is easy to see where i can follow a thread as long as possible. I take one of these numbers, and now it again is easy to eliminate alternatives and find correct numbers on other places.
Sometimes i can go on for a happy ending - if not it is obvious that the other box not chosen in the first place must be correct. OK, I take that and finalize th game. If the puzzle is very advanced may be I in the first selection can´t go further, meaning that I from that point have to make a secondary guess and go on as above mentioned (now for the moment 25% chance). It can be a lot of work doing this, but is it cheat?
Other complicated solving techniques also involve a lot of guessing where to find an xy-wing, swordfish or something
??????????
Oaxen
Back to top
View user's profile Send private message Visit poster's website
Marty R.



Joined: 12 Feb 2006
Posts: 5126
Location: Rochester, NY, USA

PostPosted: Thu Mar 12, 2009 4:54 pm    Post subject: Reply with quote

Hi oaxen,

I don't think "cheating" is an appropriate concept here. Cheating might be a valid concept in a competition if one breaks the rules. But just doing puzzles is another thing. These puzzles are intended for our amusement and anything we do with them is fine.

There are techniques that are more satisfying than others. For example, trial-and-error techniques are not satisfying to many, and many, if not most, prefer not to use them. But again, there's no cheating, just solving puzzles in any way that pleases the player.
Back to top
View user's profile Send private message
sudokutips



Joined: 10 Oct 2010
Posts: 2
Location: USA

PostPosted: Fri Oct 22, 2010 3:05 am    Post subject: Reply with quote

No I don't think you are cheating. Sounds like you have a good strategy.
Back to top
View user's profile Send private message Visit poster's website
ttt



Joined: 06 Dec 2008
Posts: 42
Location: vietnam

PostPosted: Sat Oct 23, 2010 7:57 am    Post subject: Reply with quote

Code:
coly013
....9..5..1.....3...23..7....45...7.8.....2.......64...9..1.....8..6......54....7

 *-----------------------------------------------------------------------------*
 | 367     3467    3678    | 12678   9       12478   | 168     5       12468   |
 | 5679    1       6789    | 2678    24578   2478    | 689     3       24689   |
 | 569     456     2       | 3       458     148     | 7       14689   14689   |
 |-------------------------+-------------------------+-------------------------|
 | 12369   236     4       | 5       238     12389   | 13689   7       13689   |
 | 8       3567    13679   | 179     347     13479   | 2       169     13569   |
 | 123579  2357    1379    | 12789   2378    6       | 4       189     13589   |
 |-------------------------+-------------------------+-------------------------|
 | 23467   9       367     | 278     1       23578   | 3568    2468    3468    |
 | 12347   8       137     | 279     6       23579   | 1359    1249    1349    |
 | 1236    236     5       | 4       238     2389    | 13689   12689   7       |
 *-----------------------------------------------------------------------------*

coly008
...1....87.......9..3.9.5....9.3...5.....23.....4..6....6.8..5.47...1...2........

 *-----------------------------------------------------------------------------*
 | 569     24569   245     | 1       24567   34567   | 247     23467   8       |
 | 7       124568  12458   | 23568   2456    34568   | 124     12346   9       |
 | 168     12468   3       | 2678    9       4678    | 5       12467   12467   |
 |-------------------------+-------------------------+-------------------------|
 | 168     12468   9       | 678     3       678     | 12478   12478   5       |
 | 1568    14568   14578   | 56789   1567    2       | 3       14789   147     |
 | 1358    12358   12578   | 4       157     5789    | 6       12789   127     |
 |-------------------------+-------------------------+-------------------------|
 | 139     139     6       | 2379    8       3479    | 12479   5       12347   |
 | 4       7       58      | 23569   256     1       | 289     268     236     |
 | 2       13589   158     | 35679   4567    345679  | 14789   14678   13467   |
 *-----------------------------------------------------------------------------*


Ah… ha! Let try above puzzles and tell me know how long you solve them…
I can solve them around 15’ BY LOGIC Very Happy

Good Luck…!

ttt
Back to top
View user's profile Send private message
keith



Joined: 19 Sep 2005
Posts: 3150
Location: near Detroit, Michigan, USA

PostPosted: Sun Oct 24, 2010 3:28 am    Post subject: Re: Cheating? Reply with quote

oaxen wrote:
Am I cheating - or why am I always successful solving advanced puzzles?
My method after all the basics:
Find two equal numbers in a row or a column, where they only are represented twice. Mostly there are more alternaties, but it is easy to see where i can follow a thread as long as possible. I take one of these numbers, and now it again is easy to eliminate alternatives and find correct numbers on other places.
Sometimes i can go on for a happy ending - if not it is obvious that the other box not chosen in the first place must be correct. OK, I take that and finalize th game. If the puzzle is very advanced may be I in the first selection can´t go further, meaning that I from that point have to make a secondary guess and go on as above mentioned (now for the moment 25% chance). It can be a lot of work doing this, but is it cheat?
Other complicated solving techniques also involve a lot of guessing where to find an xy-wing, swordfish or something
??????????
Oaxen

Oaxen,

I have a better method. It is called Adrianne's Thread:

http://en.wikipedia.org/wiki/Ariadne%27s_thread_%28logic%29

Start with any possibility. If that does not work, go back and pick another possibility. I am sure the Wikipedia article will reassure all of us that this is a logical scientific method for Sudoku, not trial and error.

I think this method is better than yours, because it is ALWAYS successful, AND does not require any starting logic to pick the candidates.

"Cheating" would be looking at the answer (end solution), which I assume you do not use as part of your method.

I am pleased that you have started a discussion thread where others can contribute to your method.

Keith
Back to top
View user's profile Send private message
peterj



Joined: 26 Mar 2010
Posts: 974
Location: London, UK

PostPosted: Mon Oct 25, 2010 8:40 pm    Post subject: Re: Cheating? Reply with quote

oaxen wrote:
Am I cheating - or why am I always successful solving advanced puzzles?

Sudoku is one of those pasttimes where the journey is more important than the destination. I always wonder why newspapers insist on publishing the "solution" to Sudokus - I don't care what the solution is, it is not interesting. What matters is how you get there!

If you enjoy the journey that's all that matters, at one level - but at another level some enjoy sharing that journey and some enjoy the journey having an elegance to its logic. The criticism of "trial and error" methods is that it is not a particularly interesting journey and doesn't really benefit from being shared. The criticism of "fancy logic" methods is that they are unneccessarily complex (from the point of view of finding a solution) - some might say "intellectual masturbation"!

But for me there is a tiny grain of beauty in a logical solution that is worth the effort and never appears in a trial and error approach. But each to his own and at the end of the day it's just an inconsequential little puzzle.
Back to top
View user's profile Send private message
keith



Joined: 19 Sep 2005
Posts: 3150
Location: near Detroit, Michigan, USA

PostPosted: Tue Oct 26, 2010 12:30 am    Post subject: Reply with quote

peterj,

Well said! If I may add:

> some enjoy sharing that journey and some enjoy the journey
> having an elegance to its logic.

Some enjoy learning about others' journeys, so as to improve their own future journeys.

Keith
Back to top
View user's profile Send private message
Display posts from previous:   
Post new topic   Reply to topic    dailysudoku.com Forum Index -> Solving techniques, and terminology All times are GMT
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group