# UNDF: UNDF-2026-000001004
--- a/src/Savegame/SavedGame.h
+++ b/src/Savegame/SavedGame.h
@@ -18,6 +18,7 @@
  */
 #include <map>
 #include <vector>
+#include <unordered_set>
 #include <string>
 #include "GameTime.h"
 #include "../Mod/RuleAlienMission.h"
@@ -121,1 +122,2 @@
 	std::vector<const RuleResearch*> _discovered;
+	std::unordered_set<std::string> _discoveredNames;

--- a/src/Savegame/SavedGame.cpp
+++ b/src/Savegame/SavedGame.cpp

 # Fix 1: isResearched(string) uses O(1) hash lookup instead of O(D) linear scan

@@ -1433,13 +1434,5 @@
 bool SavedGame::isResearched(const std::string &research, bool considerDebugMode) const
 {
 	if (considerDebugMode && _debug)
 		return true;
-	for (std::vector<const RuleResearch *>::const_iterator i = _discovered.begin(); i != _discovered.end(); ++i)
-	{
-		if ((*i)->getName() == research)
-			return true;
-	}
-
-	return false;
+	return _discoveredNames.count(research) != 0;
 }

 # Fix 2: Maintain _discoveredNames at all three push_back sites

@@ -500,1 +500,2 @@
 			_discovered.push_back(mod->getResearch(research));
+			_discoveredNames.insert(research);
@@ -1110,1 +1111,2 @@
 	_discovered.push_back(research);
+	_discoveredNames.insert(research->getName());
@@ -1138,1 +1140,2 @@
 			_discovered.push_back(currentQueueItem);
+			_discoveredNames.insert(currentQueueItem->getName());

 # Fix 3: getAvailableResearchProjects unlocked vector -> unordered_set

@@ -1247,7 +1250,7 @@
-	std::vector<const RuleResearch *> unlocked;
+	std::unordered_set<const RuleResearch *> unlocked;
 	for (std::vector<const RuleResearch *>::const_iterator it = _discovered.begin(); it != _discovered.end(); ++it)
 	{
 		for (std::vector<std::string>::const_iterator itUnlocked = (*it)->getUnlocked().begin(); itUnlocked != (*it)->getUnlocked().end(); ++itUnlocked)
 		{
-			unlocked.push_back(mod->getResearch(*itUnlocked, true));
+			unlocked.insert(mod->getResearch(*itUnlocked, true));
 		}
 	}
@@ -1261,1 +1264,1 @@
-		if ((considerDebugMode && _debug) || std::find(unlocked.begin(), unlocked.end(), research) != unlocked.end())
+		if ((considerDebugMode && _debug) || unlocked.count(research) != 0)