diff --git a/src/util/DataTree.cpp b/src/util/DataTree.cpp
index 6be2fc5..f30db4c 100755
--- a/src/util/DataTree.cpp
+++ b/src/util/DataTree.cpp
@@ -29,6 +29,7 @@
 #include <iomanip>
 #include <locale>
 #include <stdlib.h>
+#include <algorithm>
 
 /* DataElement class */