From 870e3b69ebe4b04aec554e88b269f70def8907a5 Mon Sep 17 00:00:00 2001
From: eug-vs <eugene@eug-vs.xyz>
Date: Sun, 29 Jan 2023 16:27:05 +0300
Subject: fix: cutoff even when hash move is not a PV node

---
 src/board/engine.rs | 15 +++++++++++++--
 1 file changed, 13 insertions(+), 2 deletions(-)

(limited to 'src/board')

diff --git a/src/board/engine.rs b/src/board/engine.rs
index f2f6d10..95d7145 100644
--- a/src/board/engine.rs
+++ b/src/board/engine.rs
@@ -289,7 +289,18 @@ impl Board {
                             principal_variation.push(transposition.mov);
                             return (transposition.score, principal_variation);
                         }
-                        _ => {} // TODO: prune when out ouf bounds
+                        NodeType::Cut => {
+                            if transposition.score >= beta {
+                                principal_variation.push(transposition.mov);
+                                return (beta, principal_variation);
+                            }
+                        }
+                        NodeType::All => {
+                            if transposition.score <= alpha {
+                                principal_variation.push(transposition.mov);
+                                return (alpha, principal_variation);
+                            }
+                        }
                     }
                 }
             }
@@ -365,7 +376,7 @@ impl Board {
                         node_type: NodeType::PV,
                         score,
                     });
-                } else {
+                } else if self.transposition().is_none() {
                     self.transposition_table[(self.hash % TTABLE_SIZE) as usize] = Some(TranspositionTableItem {
                         hash: self.hash,
                         mov,
-- 
cgit v1.2.3