diff --git a/machine_learning/adaline_learning.cpp b/machine_learning/adaline_learning.cpp
index f271289e3..6d0167a54 100644
--- a/machine_learning/adaline_learning.cpp
+++ b/machine_learning/adaline_learning.cpp
@@ -26,8 +26,8 @@
 #include <cstdlib>
 #include <ctime>
 #include <iostream>
-#include <vector>
 #include <numeric>
+#include <vector>
 
 #define MAX_ITER 500  // INT_MAX  ///< Maximum number of iterations to learn