diff --git a/crop.cpp b/crop.cpp
index 7f3fefb205c282304874c47b2d122484daf39539..411e6ed3e0d9772755cc4b4e9cb74df61b7fa81b 100644
--- a/crop.cpp
+++ b/crop.cpp
@@ -5,6 +5,7 @@
 #include "simple/file.hpp"
 #include "simple/support/enum.hpp"
 #include "simple/support/misc.hpp"
+#include "simple/support/algorithm.hpp"
 
 using namespace simple;
 using namespace std::literals;