Ages ago, I started coding up a perl-based sudoku solver and managed to get it solving lots of puzzles with only a very basic set of rules for solving them. Recently, 
alnitak (who is also writing a solver, this time in java) showed me a really nasty puzzle which neither of our solvers could completed (although a human could spot the next step). After some discussions we came up with a new solving rule, which I've implemented in my code and now allows me to solve the puzzle.
Anyway, what I'm looking for is some truly evil sudokus to test my solver with, so if you've got any nasty ones that you can send me, that would be much appreciated.
+---+---+---+ |738|.1.|.9.| |.9.|5..|74.| |..4|...|...| +---+---+---+ |64.|28.|3..| |...|...|...| |..2|.95|.87| +---+---+---+ |...|...|1..| |.87|..2|.3.| |.5.|.6.|279| +---+---+---+
Anonymous
January 20 2006, 15:11:29 UTC 15 years ago
Based on your description above, the hardest two of the five levels will defeat your solver. But all the puzzles on the site are solvable with pure logic, as you will see if you use the Solve Step feature (which offers a terse explanation).
To get the puzzles to your solver without typing the starting digits, use the Permalink link (lower right of the Fiendish Sudoku grid) to copy the puzzles to the clipboard.
- Rob
January 20 2006, 16:12:20 UTC 15 years ago