diff --git a/Data/List/LCS/HuntSzymanski.hs b/Data/List/LCS/HuntSzymanski.hs
index 306368f..e9df4ef 100644
--- a/Data/List/LCS/HuntSzymanski.hs
+++ b/Data/List/LCS/HuntSzymanski.hs
@@ -1,2 +1,2 @@
-
+{-# LANGUAGE FlexibleContexts #-}
 -----------------------------------------------------------------------------