Storing Countermoves by Ply

[AlvaroBegue]

Shouldn't that be SEE >= 0 captures? Normally you would want to search Q x protected Q before B x R.

I think I tried both ways and separating SEE == 0 captures was slightly better. But that was a few months ago and my program has improved much since then, so perhaps the result is not applicable. I am retesting it now.

I got an insignificant up by not separating SEE == 0 captures. (10998 wins, 10855 losses, 17564 draws, which means Elo +1.26 +/- 1.30). I'll leave my code the way it is for now.