Just saw a link from facebook for ShanKoDevs sudoku solver found at http://www.shankodev.com/sudoku and it seems to solve the most difficult puzzles very, very quick and even provide solutions where other online sudoku solvers claim no solution.
Can anyone else verify this.
If its true then their front ends isn't too good but there backend power is damn good!
Writing a fast brute force sudoku solver is pretty trivial. A desktop computer can solve most puzzles literally in milliseconds.
If one solver says there is a solution and another says there's no solution, one of them is wrong. Sudoku puzzles can be unambiguously classified into "solvable" and "unsolvable".
According to the check rules then it would seem as if the online sudoku solvers listed by google search isn't capable of doing their job. This one from ShanKoDev is online and when measuring the speed to and back from their server one would have to then agree that this is one of the fastest solvers I've seen so far.