Thursday, April 15, 2010

Suicide checkers is a draw - probably

During this winter, I let my suicide checkers book generator run for quite some time, expanding the size of my suicide checkers opening database from about 60'000 to over 180'000 positions. With the generator running on a machine that was twice as fast as for the 60'000 first nodes, the overall quality of the book must have improved massively. It now predicts draws for all 7 opening moves, from which I draw the conclusion in the title of this post.
With the beginning of spring I turned the generator off again - my green conscience would at least like to scavenge some waste heat for my house from book building... Furthermore, I am slightly ashamed to have a PC with a quad-core processor running on a single core only - it could be building the book at nearly 4 times the speed it is doing now, using only a little more energy if I programmed it to use all cores. With PCs nowaday having 4 or even 8 cores, I really should learn how to program a multithreaded search...

Wednesday, April 14, 2010

common Java codebase

I worked a bit on my Java checkers engine so that I can now use the same code for both my Android checkers tutor and my Java PC program - I'm glad I managed to combine the two! The only difference (and one I will probably forget to change from time to time...) is the size of the hashtable, which is obviously much smaller on the phone.
I also improved playing strength a bit, and will probably release new versions of both my Java checkers programs soon.