FAQ   Search   Memberlist   Usergroups   Register   Profile   Log in          Games  Calendar Log in to check your private messages    Sudoku file formats Goto page Previous  1, 2, 3          Sudoku Programmers Forum Index -> Software View previous topic :: View next topic   Author Message PSBlake Joined: 18 Jan 2006 Posts: 8 : Items Posted: Sat Jan 28, 2006 5:10 am    Post subject: gsf wrote: so to decode you would need a dictionary of 5,472,730,538 canonical puzzles or a function that produces a canonical puzzle given its label This is always the tradeoff in computer science: Space or speed. Do you want a smaller app, or a quicker one? In this case, I'm examining the intellectual challenge of a smaller app. In fact, the smallest. gsf wrote: but that would only give you a puzzle equivalent to the original to get the exact original you would also need the row/col permutations and the cell label permutation I'm missing the distinction here: Are you saying that (in simpler terms) for a 2x2 sudoku: Code: 10 01 is not distinct from: Code: 01 10 Because the 2 groupings are of the same shape? I wasn't aware of this, if it is the case. If it is, by my reasoning (of which I am by no means certain) then for any 9x9 Sudoku, there should be 9! (362880) essentially identical Sudoku differing in numbers, but sharing identically shaped groupings. That means I need 19 bits to represent them. I've already got 9 spare bits from the previous algorithm. Rounded to the nearest byte makes 2 bytes, making my representation 16 bytes, with some non-contiguous data fields. Messy, but small. As for competing with existing compression formats, I'm beating them. Back to top gsf Joined: 18 Aug 2005 Posts: 411 : Location: NJ USA Items Posted: Sat Jan 28, 2006 2:46 pm    Post subject: PSBlake wrote: gsf wrote: so to decode you would need a dictionary of 5,472,730,538 canonical puzzles or a function that produces a canonical puzzle given its label This is always the tradeoff in computer science: Space or speed. Do you want a smaller app, or a quicker one? In this case, I'm examining the intellectual challenge of a smaller app. In fact, the smallest. gsf wrote: but that would only give you a puzzle equivalent to the original to get the exact original you would also need the row/col permutations and the cell label permutation I'm missing the distinction here: Are you saying that (in simpler terms) for a 2x2 sudoku: Code: 10 01 is not distinct from: Code: 01 10 Because the 2 groupings are of the same shape? I wasn't aware of this, if it is the case. If it is, by my reasoning (of which I am by no means certain) then for any 9x9 Sudoku, there should be 9! (362880) essentially identical Sudoku differing in numbers, but sharing identically shaped groupings. read up on sudoku counting there are 6670903752021072936960 completed grids but only 5472730538 up to isomorphism encoding a grid in the 5472730538 only gets a member of a class of possibly >1 grids along with that encoding must be encoded the row/col cell-value permutations that transform the class member to the original grid that was to be encoded Back to top gypsy fly Joined: 06 Mar 2006 Posts: 18 : Location: Portland OR USA Items Posted: Tue Mar 14, 2006 9:43 pm    Post subject: I can see that this discussion is several months old. Nevertheless, I'll bump it up. Here's a txt format that I decided to implement for a sudoku worksheet program. This is a 9x9. The first character defines data type. C for citing the source, D for difficulty, Period (.) for puzzle in column sequence with each new line being the rows. After the second "." separator is a relative boolean string for change/no change (i.e. 0 means a given, 1 is player input). The player saves versions with a "Save As" and any valid naming convension of their choice. CThe Oregonian 03/10 D5 .000409670.111010001 .000076900.111100011 .000000003.111111110 .000001740.111110001 .640000018.001111100 .021600000.100011111 .100000000.011111111 .004320000.110001111 .062904000.100010111 A partially completed puzzle is saved thusly: CThe Oregonian 03/10 D5 .218439675.111010001 .400076902.111100011 .006002403.111111110 .000201746.111110001 .640000128.001111100 .021640009.100011111 .100060294.011111111 .004320061.110001111 .062914007.100010111 I'm going to add more data type as the need arises. Back to top Display posts from previous: All Posts1 Day7 Days2 Weeks1 Month3 Months6 Months1 Year Oldest FirstNewest First         Sudoku Programmers Forum Index -> Software All times are GMT Goto page Previous  1, 2, 3 Page 3 of 3   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