FAQ   Search   Memberlist   Usergroups   Register   Profile   Log in          Games  Calendar Log in to check your private messages    Looking for instances of the Empty Rectangle (ER)          Sudoku Programmers Forum Index -> Programming sudoku View previous topic :: View next topic   Author Message charles.trois Joined: 13 Mar 2008 Posts: 4 : Location: France Items Posted: Tue May 12, 2009 8:35 am    Post subject: Looking for instances of the Empty Rectangle (ER) Hello all, I have written an ER program that I think should work, but I cannot make sure of it, for want of good examples. Could someone give me references to one or more puzzles that do definitely exhibit an ER after one round of the basic reductions by singles and intersections? Cheers. Charles Back to top wapati Joined: 12 Jun 2007 Posts: 622 : Location: Canada Items Posted: Tue May 12, 2009 11:03 am    Post subject: Code: . 6 7|. . 4|. 2 . . 5 .|. . .|. 1 6 3 1 .|. 2 .|. . . -----+-----+----- . . .|3 7 .|. . . 2 . .|8 1 5|. . 4 . . .|. 4 2|. . . -----+-----+----- . . .|. 8 .|. 6 1 1 7 .|. . .|. 8 . . 8 .|5 . .|2 7 . Code: 2 . 3|5 . .|4 . . 7 . .|. 2 .|1 . . . 1 5|. . .|. 8 3 -----+-----+----- 3 9 .|. . .|. 5 . . . .|8 . 5|. . . . 5 .|. . .|. 1 4 -----+-----+----- 1 3 .|. . .|6 4 . . . 4|. 1 .|. . 8 . . 7|. . 4|3 . 1 Code: 8 5 9|. . 4|6 . 3 . 3 .|. . .|. . . 7 . .|6 . .|9 1 . -----+-----+----- . . 5|2 6 .|. . . . . .|. . .|. . . . . .|. 7 8|2 . . -----+-----+----- . 4 8|. . 9|. . 6 . . .|. . .|. 5 . 1 . 6|8 . .|3 9 4 Back to top daj95376 Joined: 05 Feb 2006 Posts: 349 : Items Posted: Tue May 12, 2009 3:25 pm    Post subject: This puzzle has four Empty Rectangles immediately after basics. Two of the ERs are for the same elimination. Code: Puzzle NR_004:   posted 4/30/09   DailySudoku.com  +-----------------------+  | 9 . . | . . 5 | 8 7 . |  | . 5 . | . . 8 | . . 1 |  | . . 1 | . . . | 4 5 . |  |-------+-------+-------|  | . . . | . . . | . . . |  | . . . | . 8 1 | 6 . 3 |  | 3 1 . | . 5 . | . . 8 |  |-------+-------+-------|  | 8 . 3 | . 1 . | 9 6 . |  | 5 . 4 | . . . | 1 . . |  | . 9 . | . 3 7 | . . 4 |  +-----------------------+ Code:  c3b9 Empty Rectangle => [r1c9]<>2  r1b9 Empty Rectangle => [r9c3]<>2  c9b5 Empty Rectangle => [r3c4]<>9  r5b3 turbot fish/ER  => [r3c4]<>9  r5c9 2-String Kite   => [r3c4]<>9 Back to top hobiwan Joined: 11 Feb 2008 Posts: 83 : Items Posted: Tue May 12, 2009 5:24 pm    Post subject: Four puzzles with ER directly after Singles: Code: 7...56.381.842.............5..3......4..8.7....1...24...3.........1....5.5...7.6. ..86........759...6..1...9.......83.9.6.....5..24.5.....5..438.3.18.2..6......2.. .3.8...7..48...1....745..69...74.951..4......7...2........1.....25.7...36.....7.. 5.......3.....897.697.5...........287.3.1..........1....9..1357..8765......49.... 47...........2...78..5..34..6..7..8...9.45..3.8......2741..32............9.2...5. You can generate puzzles like this using HoDoKu from the command line: Code: java -Xmx512m -jar hodoku-1.2.4.jar /s /sc er oder Code: hodoku-1.2.4.exe /s /sc er Back to top charles.trois Joined: 13 Mar 2008 Posts: 4 : Location: France Items Posted: Thu May 14, 2009 8:11 am    Post subject: Looking for instances of the Empty Rectangle (ER) Many thanks. I now have plenty of material to work on. Back to top Display posts from previous: All Posts1 Day7 Days2 Weeks1 Month3 Months6 Months1 Year Oldest FirstNewest First         Sudoku Programmers Forum Index -> Programming 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