Finally proper 9x9 jigsaw sudokus in vint.ee

Hello,

Probably the most active sudoku solvers have realised that we had fixed number of 9x9 jigsaw "templates" - the jigsaw areas were repeating time-to-time.

It is true - we had 53 different templates in use. Why? Because back in the days we could not get the random template generation to work quick enough (in extreme cases it took 30 seconds to generate one template).

Now, 13 years and 280 000 solved 9x9 jigsaw sudokus later, we can happily announce that 9x9 jigsaw tempates are totally random!

All it took was Tiit to visit my place yesterday and during the random conversation I got this idea that we could reuse logic from crossword generation to start generating 9x9 jigsaw templetes.

The fun fact is that the coding took literally 30 minutes. A little bit of testing and the functionality is live!

Any feedback is welcome!