diff --git a/examples/linear_manifold_regularizer_ex.cpp b/examples/linear_manifold_regularizer_ex.cpp
index 4c4682241..522be6c06 100755
--- a/examples/linear_manifold_regularizer_ex.cpp
+++ b/examples/linear_manifold_regularizer_ex.cpp
@@ -90,6 +90,7 @@
 #include "dlib/statistics.h"
 #include <iostream>
 #include <vector>
+#include <ctime>
 
 
 using namespace std;