Sudoku Generator

I want an application built that will allow me to generate Sudoku puzzles. I would like it to generate multiple levels of difficulty, at least 4 different levels, that all have a unique answer with out having any guessing involved but that can be solved though the many styles of Sudoku solving stratigies. I would like it to be able to create the puzzles fast and put them in a PDF document with a branded logo, ie my website url. I would like it to allow me to put in a setting such as easy, medium, hard, super hard etc.. and create 8 random puzzles of that difficulty level and place them in a PDF document with 4 puzzles on each page as well as have it have a third page with the answer key for all 8 puzzles. I am mostly interested in the beginning with 9x9 puzzles but would like it if it wasn't to much more for it to be able to allow me to do other size puzzles as well such as 4x4 and 6x6 and maybe even 16x16 but again I am mostly interested in the 9x9 and if the price isn't to much more i could do the others or save that for an extention if I am happy with the programer that I chose to do this job to do it later. I would like it to be of a software type that I could run of my computer with an easy to use GUI. I would also like it to be very random so the odds of having duplicate puzzles in a massive amount of puzzles would either be rare or not happen at all. ## Deliverables Basically all I want is to be able to create these Sudoku puzzles with the program generating 8 puzzles at a time and placing them in a PDF document with 4 puzzles per page on page one and two and a third page for the answer key so that I can upload them to my site so that users can download them and print them out to play. As I said before I want it to create the puzzles quickly and allow me to put a difficulty setting in and have it generate the 8 puzzles with answer key to that particular difficulty level. I would also like the program to have a text box so that I could enter what I want the "branded" part to be which would be printed out in the PDF documents at the bottom of each page. As said before I would like it to be able to do at least 4 levels of difficulty to generate the 8 puzzles and a setting to choose which one I want to do and a must is that it generates the puzzles quickly so that I can do multiple puzzle sets at a time to upload to my site. I would like to be able if possible and not to expensive to do the other sets of Sudoku puzzles like the 4x4, 6x6, 12x12 and maybe even 16x16 and have a setting to choose which one to do but we can discuss this after determining how much extra it would be to preform but I am interested in this as it gives me the ability to offer Sudoku style puzzles that most sites do not offer to their users. I am not sure what type of program language would be the best to do this but I have seen some on the internet that use C++ and Visual Basic. The language isn't as important as is the quality and speed of the program. For the 9x9 puzzles only I would like it to have a setting called something like "Daily Sudoku" that would create a PDF document with the same 8 puzzles with answer sheet but have it where instead of printing 8 puzzles to the PDF file of the same level that I could do say 2 of each level depending on the amount of levels we decide on. This is also a very important feature that must be included in the program.