The number is up for Sudoku

[Doggy Styles]

Indeed : any that require x-wing (or worse triple x-wing) I find very difficult.....

Ah, now somebody else mentioned that to me. What is it?

[BrilloPad]

I could never quite get the hang of Super Fiendish.

Indeed : any that require x-wing (or worse triple x-wing) I find very difficult.....

[NotAllThere]

Sudoku doesn't require any logical deduction; I worked that out years ago, and why I find them so dull. I prefer the Killers on timesonline. Generally can do them in about 50% of the published time.

[TykeMerc]

I don't care, I have a Sodoku puzzle generator on my PDA so I can play as many times as I like, I enjoy the puzzles.

[thunderlizard]

yup, isn't it just a case of encoding the same rules that your brain has to go through?


Like this xslt behemoth:
http://ajwelch.blogspot.com/2006/05/...s-fast_02.html

[EternalOptimist]

There's so little alcohol in fosters, that you could probably drive after 8 pints!

maybe so, but I am such a delicate flower

[Doggy Styles]

I could never quite get the hang of Super Fiendish.

[bored]

Or alternatively

Write a backtracking solver (takes about 15 mins).
Plug in any sudoku.
Receive an answer in <1s.

:

[Moscow Mule]

you try doing it after eight pints of fosters smart @rse

There's so little alcohol in fosters, that you could probably drive after 8 pints!

[EternalOptimist]

Darn it, didn't know it was a problem looking for a solution.

I have myself discovered a simple algorithm to solve Soduko too:

You look at a square and choose a number that is not a member of the set of incorrect numbers.

This itself breaks down into a simple counting exercise.

Further detail, like the puzzle itself, is rather trivial.

you try doing it after eight pints of fosters smart @rse

[threaded]

Darn it, didn't know it was a problem looking for a solution.

I have myself discovered a simple algorithm to solve Soduko too:

You look at a square and choose a number that is not a member of the set of incorrect numbers.

This itself breaks down into a simple counting exercise.

Further detail, like the puzzle itself, is rather trivial.

[BrilloPad]

http://www.timesonline.co.uk/tol/new...cle5950524.ece

IT’S fiendish, it may even be diabolical, and it’s the solution to Sudoku. To the outrage of the puzzle’s fans, an American computer scientist will tomorrow reveal a formula for solving any Sudoku problem, no matter how difficult.

James Crook, an emeritus professor in South Carolina, will be publishing his “pen-and-paper algorithm for solving Sudoku puzzles” on the web-site of the American Mathematical Society. While his paper runs to nine pages of detailed argument, the algorithm boils down to five logical steps.

This weekend, in the face of mounting criticism that he is taking all the fun out of the puzzle phenomenon, the former Winthrop University don declined to discuss what he describes as a “trivial puzzle”.

Fans are aghast. Colin Dexter, author of the Inspector Morse crime novels and a puzzle enthusiast, said: “I’m sorry to hear somebody’s discovered how to do it. It’s like using a computer program to work out crossword anagrams — it takes all the fun and struggle out of it.”

Nina Pell, a 21-year-old mathematics student at Sheffield University, who has twice won The Times UK National Sudoku championship, said: “The method is similar to my own Sudoku-solving strategy and confirms I’m solving it the correct way.”

Dr Gareth Moore, who compiles puzzles for Sudoku Pro magazine, said: “Crook’s algorithm might work, but the fun of Sudoku is the logical thinking by which you turn an intimidating problem into an enjoyable exercise.”

The Crook algorithm is the first mathematical proof of how to solve the puzzle. Not even Howard Garns, the Indianapolis architect who devised Sudoku in 1979, could promise that.

However, all is not lost. Crook’s system requires players to mark up empty cells in a Sudoku grid with all possible remaining numbers and, by comparing number sets, to labour through a “tree” of options that eventually produces a solution. The drawback: it takes ages – typically an hour. Yet through logic and intuition, most Sudoku puzzles can be solved in 20 minutes or less.

Since The Times introduced Sudoku in 2004, 3m Britons have become players.