AI

This is no AI... This is just a computer calculating possibilities. It solves a sudoku in now way a person would! So it's not AI.
Furthermore, I get notices everywhere and I cant upload files and even when both are fixed, the rest doesnt work.
Nice class!

I t was not me (the author of the class) that categorized this as AI, but the webmaster of PHPClasses. Nevertheless, there are some AI aspects to the class: it only does something if you choose a rule to try solving the puzzle.
I have solved many Sudoku's by hand, and I always use similar strategies to solve the puzzle as the class does. It depends on your definition of AI. How should the class have worked if it would have satisfied your definition?

As an alternative I could have programmed a brute-force tree searching algorithm. That would have been no fun, because then it solves the puzzle mechanically. Now I sometimes use the solver to see where my solution of a difficult Sudoku went wrong, or how I could continue if I am stuck.

I am not really sure why you have problems with up-and downloading. If you send me more details, I will try to help you.