diff --git a/c++/itertools/itertools.hpp b/c++/itertools/itertools.hpp
index 31821f1..a916f9d 100644
--- a/c++/itertools/itertools.hpp
+++ b/c++/itertools/itertools.hpp
@@ -20,6 +20,7 @@
 #include <iterator>
 #include <iostream>
 #include <exception>
+#include <algorithm>
 
 namespace itertools {