diff --git a/examples/listsort/listsort.ez b/examples/listsort/listsort.ez
index d2958b76a2af004287a171aa0aca118afb99079e..10f979ad731d99e4207ecc085fb06c22368c2190 100755
--- a/examples/listsort/listsort.ez
+++ b/examples/listsort/listsort.ez
@@ -12,7 +12,7 @@ _________________________________________________________*/
 \User declarations:
   int SIZE=10;
   double pMutPerGene=0.4;
-
+  #include<cstring>
   inline void swap(int& a,int& b) {int c=a; a=b; b=c;}
 \end