FAQ   Search   Memberlist   Usergroups   Register   Profile   Log in          Games  Calendar Log in to check your private messages    Guesswork?          Sudoku Programmers Forum Index -> Solving sudoku View previous topic :: View next topic   Author Message Agent Allen Joined: 01 Oct 2005 Posts: 34 : Items Posted: Tue Mar 14, 2006 9:43 pm    Post subject: Guesswork? It has been suggested that this puzzle: Code: ...|75.|... .3.|.48|.2. 1..|...|..6 ----------- .4.|...|..8 79.|...|.31 2..|...|.7. ----------- 5..|...|..7 .8.|32.|.4. ...|.69|... Requires guesswork to solve. Can’t say I agree. Thoughts anyone? NB: If it looks familiar it was the final puzzle in the world Sudoku championships in Lucca, Italy concluding 11th March 2006. See the report in the London Times Monday 13 March. It took the world champion (Jana Tylova) about 15 minutes. It took me about 50. It is implied in the article that the runners up thought this puzzle required guesswork. _________________ Agent A Back to top Ruud Site Admin Joined: 17 Sep 2005 Posts: 708 : Location: Netherlands Items Posted: Tue Mar 14, 2006 10:44 pm    Post subject: No guesswork. Naked pair, hidden pair, X-Wing. I also spotted 2 useless finned X-Wings. Ruud. Back to top gypsy fly Joined: 06 Mar 2006 Posts: 18 : Location: Portland OR USA Items Posted: Wed Mar 15, 2006 12:00 am    Post subject: This is inspiring. I'll clip this post and share it with my kids. Just to show that even the grand masters can be blind to a higher level logical technique. At their level, a single in a column, row or box may be cause for a guess!! At least until they learn the basic rule of inclusiveness and count properly from 1 to 9 and know what's missing. I suppose guessing is the gateway to a higher level of cognition and logic. Cheers! Back to top Ruud Site Admin Joined: 17 Sep 2005 Posts: 708 : Location: Netherlands Items Posted: Wed Mar 15, 2006 1:07 am    Post subject: gypsy fly wrote: Just to show that even the grand masters can be blind to a higher level logical technique. It may also show that grand masters in particular do not like to admit that somebody else is better. Ruud. Back to top angusj Site Admin Joined: 18 Jun 2005 Posts: 406 : Items Posted: Wed Mar 15, 2006 2:51 am    Post subject: gypsy fly wrote: Just to show that even the grand masters can be blind to a higher level logical technique. I'm not sure I agree. When solving time is critical (eg when competing against others), there comes a point where trial and error is definitely faster than hunting through an arsenal of logical techniques that might progress a puzzle. (Unfortunately, I suspect that this adds a degree of luck to who wins since it's likely to be the person who guesses the right candidate first time.) Back to top gypsy fly Joined: 06 Mar 2006 Posts: 18 : Location: Portland OR USA Items Posted: Wed Mar 15, 2006 4:49 am    Post subject: True. Given enough time, those who are capable would be able. Since it's a race against time, then it's good sport. I wonder if those who cried "guesswork" took the time afterwards to review the puzzle before harping "foul"? I'm just beginning to learn advanced techniques. As I learn them, I use less guesswork. My delight is that inspite of more frequent bouts of "senior moments", I can still think. Given time, I found logical solutions to puzzles using techniques whose names I would soon learn. Isn't the discovery the real kicker? By the way, I need a name/label for the following phenomenon: If one starts a puzzle scanning in order from 1 - 9, one ends up carving a different path from another who goes from 9 - 1 or even from greater frequency to less, etc. What would you call this phenomenon? Back to top angusj Site Admin Joined: 18 Jun 2005 Posts: 406 : Items Posted: Wed Mar 15, 2006 5:10 am    Post subject: gypsy fly wrote: What would you call this phenomenon? "101 ways to skin a cat." Back to top doctortray Joined: 25 Jan 2006 Posts: 32 : Items Posted: Wed Mar 15, 2006 11:21 am    Post subject: Hey Agent Alan, dont mean to mix between the different forums, but saw a thread you posted which said that you had a GUI front end written in Java, that you were willing to share? That offer still open? Would be a major help in my College Project. Back to top Agent Allen Joined: 01 Oct 2005 Posts: 34 : Items Posted: Wed Mar 15, 2006 8:39 pm    Post subject: More Facts gypsy fly wrote: I wonder if those who cried "guesswork" took the time afterwards to review the puzzle before harping "foul"? I should assume they didn't. The comments are documented as being made on the bus to the prize giving so it seems unlikely they had time to review the puzzle. It all seems like sore losing to me. Angusj I know what you're saying, but remember it was the runners up who'd resorted to trial and error... Perhaps if you resort to T&E then you are going to lose to someone who sees the direct deductive method. Perhaps thats what makes a winner and a runner up... Has anyone else out there sat down with pen and paper and done this one? It's a toughie, but a goodie. _________________ Agent A Back to top Display posts from previous: All Posts1 Day7 Days2 Weeks1 Month3 Months6 Months1 Year Oldest FirstNewest First         Sudoku Programmers Forum Index -> Solving sudoku All times are GMT Page 1 of 1   Jump to: Select a forum Sudoku----------------Solving sudokuSetting sudokuProgramming sudokuThe mathematics of sudokuExotic sudoku Library----------------PuzzlesSoftwareSudoku elsewhere Not sudoku----------------Random thoughtsForum feedback  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 Igloo Theme Version 1.0 :: Created By: Andrew Charron