Do not claim repetition after null move
authorMarco Costalba <mcostalba@gmail.com>
Wed, 7 Oct 2009 08:03:17 +0000 (09:03 +0100)
committerMarco Costalba <mcostalba@gmail.com>
Fri, 9 Oct 2009 02:55:10 +0000 (03:55 +0100)
commit64d6ba2e98f29db8e853071b635ae4ebd59c24f0
tree3c04311534cc1556dc7723e7190f730ab4251d7f
parent5a5dc6fa109990920560ca9bed8cf7be34f2eba1
Do not claim repetition after null move

Null moves can artificially create a repetition
draw where instead there is no one.

So use a second counter to reset history after
a null move.

Idea from Joona.

After 999 games at 1+0

Mod vs Orig +238 =553 -208 51.50%  514.5/999  +10 ELO

Signed-off-by: Marco Costalba <mcostalba@gmail.com>
src/position.cpp
src/position.h