dml wrote:Still not found gsfr and seuxr , I see no clear indications on http pointeurs where to load the files "gsf" or "gsfr" . Probably better to have the lattest versions.
There is sno such program as "gsf". There is a program called "sudoku" that is made by gsf and can be downloaded
here. Please read ravel's post for how to use it. In that same post there is a link to a page where you can download dukuso's program, called suexrat9. There is no difference between 'gsf' and 'gsfr', I think some people only use gsfr as short for 'gsf rating'.
dml wrote:I ask the question because one guy claims to have found the hardest sudoku. This seems to me not acceptable claim if there is not an accepted way to quantify the difficulty.
My advice, enter it into
Sudoku Explainer, press 'F9', if it gives you a rating (might take several minutes), then it isn't the hardest sudoku. If it cannot rate it, try gsf's program with these options:
-B -q'FNP(FNBTHWX)V(8)-G' -f%Q
if it gives you a rating, then it isn't the hardest sudoku. If it cannot rate it, try again with these options:
-B -q'FNP(FNBTHWXY)V(9)-G' -f%Q
if it gives a rating < 99960, then it isn't the hardest. If it gives a rating > 99960, or doesn't rate it at all, then it probably is the hardest known.
dml wrote:Also I see sometimes notation [99960 Y] , what Y means?
The Y makes the difference between the two options for gsf's program I gave you. The first one uses techniques up to coloring within the propositions (forcing nets), the second one has a Y added to the line, which means that it uses techniques upto multicoloring within the propositions.
dml wrote:It would be nice to have one program to evaluate the human difficulty to resolve a grid. Are there some people working on this problem?
Many have tried, many have succeeded quite well when it comes to puzzles that the normal human usually solves. The rating gets a lot harder when you start discussing monster puzzles like the one in this thread.
RW