diff --git a/src/scanscalar.cpp b/src/scanscalar.cpp
index 165742e..8253b8d 100644
--- a/src/scanscalar.cpp
+++ b/src/scanscalar.cpp
@@ -1,6 +1,9 @@
+#include "scanscalar.h"
+
+#include <algorithm>
+
 #include "exp.h"
 #include "regeximpl.h"
-#include "scanscalar.h"
 #include "stream.h"
 #include "yaml-cpp/exceptions.h"  // IWYU pragma: keep