Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
Groups > comp.lang.python > #88005
| References | <87r3sdnw5t.fsf@elektro.pacujo.net> <4e81bdb9-52db-46e6-b449-d4241cb2a3f2@googlegroups.com> <87twx8amww.fsf@elektro.pacujo.net> <mailman.159.1427314248.10327.python-list@python.org> <87iodoakft.fsf@elektro.pacujo.net> |
|---|---|
| From | Ian Kelly <ian.g.kelly@gmail.com> |
| Date | 2015-03-25 18:07 -0600 |
| Subject | Re: Sudoku solver |
| Newsgroups | comp.lang.python |
| Message-ID | <mailman.171.1427328485.10327.python-list@python.org> (permalink) |
On Wed, Mar 25, 2015 at 2:31 PM, Marko Rauhamaa <marko@pacujo.net> wrote: > Ian Kelly <ian.g.kelly@gmail.com>: > >> The test puzzle that you posted has 23 values already filled in. How >> does it perform on harder puzzles with only 17 clues (the proven >> minimum)? One would expect it to be around a million times slower. > > Just try it. The example had a minimum of clues (drop one clue and > you'll get multiple solutions). > > <URL: http://www.telegraph.co.uk/news/science/science-news/9359579/W > orlds-hardest-sudoku-can-you-crack-it.html> mentions this puzzle: > > ======================================================================== > 8 . . . . . . . . > . . 3 6 . . . . . > . 7 . . 9 . 2 . . > . 5 . . . 7 . . . > . . . . 4 5 7 . . > . . . 1 . . . 3 . > . . 1 . . . . 6 8 > . . 8 5 . . . 1 . > . 9 . . . . 4 . . > ======================================================================== > > It takes about 2 seconds for my Python program to find the answer but it > spends a total of 110 seconds to exhaust the problem space. > > The analogous C program finished the whole thing in 200 milliseconds. "Hard" for a human doesn't necessarily mean "hard" for a programmatic solver in this case. Try your solver on this one: $ cat sudoku2.dat . . . 7 . . . . . 1 . . . . . . . . . . . 4 3 . 2 . . . . . . . . . . 6 . . . 5 . 9 . . . . . . . . . 4 1 8 . . . . 8 1 . . . . . 2 . . . . 5 . . 4 . . . . 3 . . I tried the first puzzle you posted, and it took about a second. I then started running it on this one before I started typing up this post, and it hasn't finished yet. While that was running, I then tried running Norvig's solver on this puzzle, and it completed in about 0.07 seconds. For the curious, this puzzle was arbitrarily collected from http://theconversation.com/good-at-sudoku-heres-some-youll-never-complete-5234
Back to comp.lang.python | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread
Sudoku solver Marko Rauhamaa <marko@pacujo.net> - 2015-03-25 13:39 +0200
Re: Sudoku solver John Ladasky <john_ladasky@sbcglobal.net> - 2015-03-25 11:44 -0700
Re: Sudoku solver Ian Kelly <ian.g.kelly@gmail.com> - 2015-03-25 13:05 -0600
Re: Sudoku solver Marko Rauhamaa <marko@pacujo.net> - 2015-03-25 21:37 +0200
Re: Sudoku solver Ian Kelly <ian.g.kelly@gmail.com> - 2015-03-25 14:09 -0600
Re: Sudoku solver Marko Rauhamaa <marko@pacujo.net> - 2015-03-25 22:31 +0200
Re: Sudoku solver Chris Angelico <rosuav@gmail.com> - 2015-03-26 09:40 +1100
Re: Sudoku solver Ian Kelly <ian.g.kelly@gmail.com> - 2015-03-25 18:07 -0600
Re: Sudoku solver BartC <bc@freeuk.com> - 2015-03-27 20:04 +0000
Re: Sudoku solver Abhiram R <abhi.darkness@gmail.com> - 2015-03-26 08:26 +0530
Re: Sudoku solver Ian Kelly <ian.g.kelly@gmail.com> - 2015-03-25 21:24 -0600
Re: Sudoku solver Abhiram R <abhi.darkness@gmail.com> - 2015-03-26 08:58 +0530
Re: Sudoku solver Marko Rauhamaa <marko@pacujo.net> - 2015-03-26 14:13 +0200
Re: Sudoku solver Marko Rauhamaa <marko@pacujo.net> - 2015-03-26 16:15 +0200
Re: Sudoku solver albert@spenarnc.xs4all.nl (Albert van der Horst) - 2015-04-10 23:10 +0000
Re: Sudoku solver Sayth <flebber.crue@gmail.com> - 2015-03-27 20:39 -0700
Re: Sudoku solver BartC <bc@freeuk.com> - 2015-03-28 23:50 +0000
Re: Sudoku solver Chris Angelico <rosuav@gmail.com> - 2015-03-29 11:12 +1100
Re: Sudoku solver BartC <bc@freeuk.com> - 2015-03-29 21:59 +0100
Re: Sudoku solver Mark Lawrence <breamoreboy@yahoo.co.uk> - 2015-03-29 22:19 +0100
Re: Sudoku solver BartC <bc@freeuk.com> - 2015-03-29 22:59 +0100
Re: Sudoku solver Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-03-29 14:06 +1100
Re: Sudoku solver Chris Angelico <rosuav@gmail.com> - 2015-03-29 15:10 +1100
Re: Sudoku solver Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-03-29 21:35 +1100
Re: Sudoku solver Chris Angelico <rosuav@gmail.com> - 2015-03-29 21:54 +1100
Re: Sudoku solver BartC <bc@freeuk.com> - 2015-03-29 13:01 +0100
Re: Sudoku solver BartC <bc@freeuk.com> - 2015-03-29 16:23 +0100
Re: Sudoku solver Christian Gollwitzer <auriocus@gmx.de> - 2015-03-29 09:57 +0200
Re: Sudoku solver BartC <bc@freeuk.com> - 2015-03-30 11:54 +0100
Re: Sudoku solver BartC <bc@freeuk.com> - 2015-03-29 12:25 +0100
Re: Sudoku solver Marko Rauhamaa <marko@pacujo.net> - 2015-03-29 21:03 +0300
Re: Sudoku solver Mark Lawrence <breamoreboy@yahoo.co.uk> - 2015-03-29 19:26 +0100
Re: Sudoku solver Marko Rauhamaa <marko@pacujo.net> - 2015-03-29 21:33 +0300
Re: Sudoku solver BartC <bc@freeuk.com> - 2015-03-29 22:11 +0100
Re: Sudoku solver Ian Kelly <ian.g.kelly@gmail.com> - 2015-03-30 00:50 -0600
Re: Sudoku solver Christian Gollwitzer <auriocus@gmx.de> - 2015-03-30 09:13 +0200
Re: Sudoku solver Ian Kelly <ian.g.kelly@gmail.com> - 2015-03-30 01:29 -0600
Re: Sudoku solver Marko Rauhamaa <marko@pacujo.net> - 2015-03-30 12:16 +0300
Re: Sudoku solver Dave Angel <davea@davea.name> - 2015-03-30 04:16 -0400
Re: Sudoku solver Ian Kelly <ian.g.kelly@gmail.com> - 2015-03-30 02:57 -0600
Re: Sudoku solver Chris Angelico <rosuav@gmail.com> - 2015-03-30 20:13 +1100
Re: Sudoku solver Mark Lawrence <breamoreboy@yahoo.co.uk> - 2015-03-29 22:21 +0100
Re: Sudoku solver BartC <bc@freeuk.com> - 2015-03-29 23:17 +0100
Re: Sudoku solver Seymore4Head <Seymore4Head@Hotmail.invalid> - 2015-03-29 21:40 -0400
Re: Sudoku solver Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-03-26 09:50 +1100
Re: Sudoku solver Mark Lawrence <breamoreboy@yahoo.co.uk> - 2015-03-25 23:04 +0000
Re: Sudoku solver Christian Gollwitzer <auriocus@gmx.de> - 2015-03-27 07:40 +0100
Re: Sudoku solver "Frank Millman" <frank@chagford.com> - 2015-03-26 10:19 +0200
Re: Sudoku solver Marko Rauhamaa <marko@pacujo.net> - 2015-03-26 14:26 +0200
Re: Sudoku solver Chris Angelico <rosuav@gmail.com> - 2015-03-26 23:37 +1100
Re: Sudoku solver Ian Kelly <ian.g.kelly@gmail.com> - 2015-03-26 07:15 -0600
Re: Sudoku solver Marko Rauhamaa <marko@pacujo.net> - 2015-03-26 16:23 +0200
Re: Sudoku solver Ian Kelly <ian.g.kelly@gmail.com> - 2015-03-26 09:06 -0600
Re: Sudoku solver Marko Rauhamaa <marko@pacujo.net> - 2015-03-26 17:48 +0200
Re: Sudoku solver Ian Kelly <ian.g.kelly@gmail.com> - 2015-03-26 10:20 -0600
Re: Sudoku solver Marko Rauhamaa <marko@pacujo.net> - 2015-03-26 18:47 +0200
Re: Sudoku solver Dave Angel <davea@davea.name> - 2015-03-26 10:14 -0400
Re: Sudoku solver Chris Angelico <rosuav@gmail.com> - 2015-03-27 01:41 +1100
Re: Sudoku solver Dave Angel <davea@davea.name> - 2015-03-26 11:03 -0400
Re: Sudoku solver Marko Rauhamaa <marko@pacujo.net> - 2015-03-26 17:42 +0200
Re: Sudoku solver Pete Forman <petef4+usenet@gmail.com> - 2015-03-26 22:24 +0000
Re: Sudoku solver Chris Angelico <rosuav@gmail.com> - 2015-03-27 02:21 +1100
Re: Sudoku solver Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2015-03-26 20:42 -0400
Re: Sudoku solver Dave Angel <davea@davea.name> - 2015-03-27 09:14 -0400
Re: Sudoku solver Chris Angelico <rosuav@gmail.com> - 2015-03-28 00:25 +1100
Re: Sudoku solver "Frank Millman" <frank@chagford.com> - 2015-03-27 15:35 +0200
Re: Sudoku solver Marko Rauhamaa <marko@pacujo.net> - 2015-03-27 15:56 +0200
Re: Sudoku solver Dave Angel <davea@davea.name> - 2015-03-27 10:09 -0400
Re: Sudoku solver sohcahtoa82@gmail.com - 2015-03-27 11:18 -0700
Re: Sudoku solver Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-03-28 12:46 +1100
Re: Sudoku solver Larry Hudson <orgnut@yahoo.com> - 2015-03-27 16:48 -0700
Re: Sudoku solver Chris Angelico <rosuav@gmail.com> - 2015-03-28 01:07 +1100
Re: Sudoku solver Chris Angelico <rosuav@gmail.com> - 2015-03-28 01:19 +1100
Re: Sudoku solver Gregory Ewing <greg.ewing@canterbury.ac.nz> - 2015-03-28 14:13 +1300
Re: Sudoku solver Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2015-03-28 12:40 +1100
Re: Sudoku solver Ian Kelly <ian.g.kelly@gmail.com> - 2015-03-28 02:24 -0600
Re: Sudoku solver Mark Lawrence <breamoreboy@yahoo.co.uk> - 2015-03-27 16:03 +0000
Re: Sudoku solver Virgil Stokes <vs@it.uu.se> - 2015-03-28 19:36 +0100
Re: Sudoku solver Dave Angel <davea@davea.name> - 2015-03-27 09:48 -0400
Re: Sudoku solver Dave Angel <davea@davea.name> - 2015-03-27 09:52 -0400
Re: Sudoku solver Chris Angelico <rosuav@gmail.com> - 2015-03-28 00:58 +1100
Re: Sudoku solver mr.smittye@gmail.com - 2015-03-29 16:39 -0700
Re: Sudoku solver Marko Rauhamaa <marko@pacujo.net> - 2015-03-30 12:24 +0300
csiph-web