At this moment I already can generate a fully filled in, complete sudoku field (any square size). I want playable sudoku puzzle generated out of these fields, with different difficulty levels (at least 3 levels). The puzzles that are made should always have one and only one solution (unique). The difficulty levels should not be created by leaving out more numbers, but rather by different techniques like Naked Single, Hidden Single, Block and Column / Row Interactions, Block / Block Interactions, Naked Subset, Hidden Subset, X-Wing, Swordfish, XY-Wing, XYZ-Wing, Colouring, Remote Pairs, XY Chains. Furthermore, after creating this puzzle, there should be a function that solves it, to prove the generated puzzle is indeed solvable.
1) Complete and fully-functional working program(s) in executable form as well as complete source code of all work done.
2) Deliverables must be in ready-to-run condition, as follows (depending on the nature of the deliverables):
a) For web sites or other server-side deliverables intended to only ever exist in one place in the Buyer's environment--Deliverables must be installed by the Seller in ready-to-run condition in the Buyer's environment.
b) For all others including desktop software or software the buyer intends to distribute: A software installation package that will install the software in ready-to-run condition on the platform(s) specified in this bid request.
3) All deliverables will be considered "work made for hire" under U.S. Copyright law. Buyer will receive exclusive and complete copyrights to all work purchased. (No GPL, GNU, 3rd party components, etc. unless all copyright ramifications are explained AND AGREED TO by the buyer on the site per the coder's Seller Legal Agreement).