I don't know of any off-hand. I was only solving, not creating. It's an interesting algorithm, probably. I sat here thinking about ways to do it, but, as usual, I have billable work to do. <g> About the same time I did the Sudoku solution code, I also did a program that generates mazes and I found a nice site to get that algorithm by Googling "Maze Creation Algorithm" or something close to that wording.

>Russell, thanks.
>Can you point me to the site where the theory behind the puzzle creation is represented clearly and in short terms?
>