Simplify Futility Move Count

[stockfish] / src / search.cpp

diff --git a/src/search.cpp b/src/search.cpp
index f1416a74091e1db17c21571618eb1a892721c266..c3ebf9abc302dd0974e25fef4a6bc32d19e43956 100644 (file)
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -79,7 +79,7 @@ namespace {
   }
 
   constexpr int futility_move_count(bool improving, Depth depth) {
-    return (5 + depth * depth) * (1 + improving) / 2 - 1;
+    return (4 + depth * depth) / (2 - improving);
   }
 
   // History and stats update bonus, based on depth