On Monday 01 December 2008 1:39:13 pm Bertram Felgenhauer wrote:
As one of the posters there points out, for n=100 the program doesn't actually backtrack if the 'loneliest neighbour' heuristic is used. Do any of our programs finish quickly for n=99? The Python one doesn't.
Nothing I tried finished. Do you have any figures on how much backtracking needs to be done to find a solution for n=99 (there is a solution, right?)? I tweaked the continuation version to print k when it backtracks, and it continuously spit out numbers around 9790. I get the feeling it doesn't matter how fast your backtracking infrastructure is in this case as long as you use the same general algorithm. On a long shot, I even tried using Logic's alternate bind based on fair choice, but that didn't seem to be any better. -- Dan