Tweak IID search depth for drop variants

crazyhouse STC
LLR: -2.95 (-2.94,2.94) [0.00,10.00]
Total: 24753 W: 12186 L: 11930 D: 637
http://35.161.250.236:6543/tests/view/5c1be4b96e23db24728955e0

crazyhouse LTC
LLR: -2.97 (-2.94,2.94) [0.00,10.00]
Total: 12175 W: 5928 L: 5853 D: 394
http://35.161.250.236:6543/tests/view/5c1bfc826e23db24728955e6

diff --git a/src/search.cpp b/src/search.cpp
index 0439919..c82fe32 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -843,7 +843,7 @@ namespace {
     if (    depth >= (8 - 2 * pos.captures_to_hand()) * ONE_PLY
         && !ttMove)
     {
-        search<NT>(pos, ss, alpha, beta, depth - 7 * ONE_PLY, cutNode);
+        search<NT>(pos, ss, alpha, beta, depth - (7 - 2 * pos.captures_to_hand()) * ONE_PLY, cutNode);
 
         tte = TT.probe(posKey, ttHit);
         ttValue = ttHit ? value_from_tt(tte->value(), ss->ply) : VALUE_NONE;