Error of not marking read only functions in class QueueElement corrected
diff --git a/ConcQueue.h b/ConcQueue.h
index 0ab762f..5404ee5 100644
--- a/ConcQueue.h
+++ b/ConcQueue.h
@@ -20,7 +20,7 @@
 	{
 	}
 
-	data_val_type GetData()
+	data_val_type GetData() const
 	{
 		return data_value;
 	}
@@ -78,7 +78,7 @@
 		}
 	}
 	
-	QueueElement<data_val_type>* AddElement(data_val_type val)
+	const QueueElement<data_val_type>* AddElement(data_val_type val)
 	{
 		QueueElement<data_val_type> *temp = NULL;
 		lock_queue current_lock;