From 652c4c744d6e869c8735cadac5033ff2f7e1de55 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Eduardo=20C=C3=A1ceres?=
 <eduardo.caceresdelacalle@gmail.com>
Date: Sat, 18 Jan 2025 23:44:05 +0100
Subject: [PATCH] Ensure that `HashfullPermillApprox` doesn't fail when tt
 length < 1k items

---
 src/Lynx/Model/TranspositionTable.cs | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/src/Lynx/Model/TranspositionTable.cs b/src/Lynx/Model/TranspositionTable.cs
index d9628ada8..d78eb911c 100644
--- a/src/Lynx/Model/TranspositionTable.cs
+++ b/src/Lynx/Model/TranspositionTable.cs
@@ -126,11 +126,15 @@ public int HashfullPermill() => _tt.Length > 0
     public readonly int HashfullPermillApprox()
     {
         int items = 0;
-        for (int i = 0; i < 1000; ++i)
+
+        if (_tt.Length >= 1_000)
         {
-            if (_tt[i].Key != default)
+            for (int i = 0; i < 1_000; ++i)
             {
-                ++items;
+                if (_tt[i].Key != default)
+                {
+                    ++items;
+                }
             }
         }