diff --git a/src/fenrir/core/memoryManager.py b/src/fenrir/core/memoryManager.py
index 15bee58b..0c2af5e3 100644
--- a/src/fenrir/core/memoryManager.py
+++ b/src/fenrir/core/memoryManager.py
@@ -12,26 +12,55 @@ class inputManager():
         self.listStorage = {}
     def initialize(self, environment):
         self.env = environment
-    def addValueList(self, name, value):
+    def addValueToFirstIndex(self, name, value):
         pass
     def addIndexList(self, name, maxLength = None, currList = [], currIndex = 0):
         self.listStorage[name] = {'list': currList, 'index': currIndex, 'maxLength': maxLength}
-    def getNextIndexListElement(self, name):
-        pass
-    def getPrefIndexListElement(self, name):
-        pass  
-    def getFirstIndexListElement(self, name):
-        pass
-    def getLastIndexListElement(self, name):
-        pass  
+    def getNextIndex(self, name):
+        if self.isIndexListEmpty(name):
+            self.listStorage[name]['index'] = -1
+            return False
+        self.listStorage[name]['index'] += 1
+        if self.listStorage[name]['index'] > len(self.listStorage[name]['list']) -1:
+            self.listStorage[name]['index'] = 0
+        return True    
+    def setPrefIndex(self, name):
+        if self.isIndexListEmpty(name):
+            self.listStorage[name]['index'] = -1
+            return False
+    def setFirstIndex(self, name):
+        if self.isIndexListEmpty(name):
+            self.listStorage[name]['index'] = -1
+            return False
+        self.listStorage[name]['index'] = 0
+        return True  
+    def setLastIndex(self, name):
+        if self.isIndexListEmpty(name):
+            self.listStorage[name]['index'] = -1
+            return False
+        self.listStorage[name]['index'] = self.listStorage[name]['list'] -1 
+        return True  
+    def clearCurrentIndexList(self, name):
+        self.listStorage[name]['index'] = []
+        self.listStorage[name]['index'] = -1
     def getCurrentIndex(self,name):
+        if self.isIndexListEmpty(name):
+            self.listStorage[name]['index'] = -1
+            return False        
         try:        
-            return self.listStorage[name]['list']['index']    
+            return self.listStorage[name]['index']    
         except:
-            retrun 0
+            retrun -1
+    def isIndexListEmpty(self, name):
+        return len(self.listStorage[name]['list']) == 0
     def getIndexListElement(self, name):
+        if self.isIndexListEmpty(name):
+            self.listStorage[name]['index'] = -1
+            return False        
         currIndex = self.getCurrentIndex(name)
+        if currIndex == -1:
+            return None
         try:        
             return self.listStorage[name]['list'][currIndex]
         except:
-            return []
+            return None