14 Mar
2020
14 Mar
'20
11:18 a.m.
On Sat, Mar 14, 2020 at 8:01 AM Bernie Cosell <bernie@fantasyfarm.com> wrote:
I'm wondering about such things like: after you generate a grid, how do you figure out which cells to give as clues, recalling that the clues should be optimal for that grid [that is, yield a unique solution and have the solution not be unique if any clue is removed]? How do they determine the "difficulty" of a puzzle?
One way is to remove numbers and then solve the puzzle using dancing links to find all solutions. Backtrack if there's more than one solution. The difficulty is the runtime. http://www-cs-faculty.stanford.edu/~uno/papers/dancing-color.ps.gz -- Mike Stay - metaweta@gmail.com http://math.ucr.edu/~mike https://reperiendi.wordpress.com