diff --git a/exercises/22_class_template/main.cpp b/exercises/22_class_template/main.cpp
index 2a702ecc0..d4985d904 100644
--- a/exercises/22_class_template/main.cpp
+++ b/exercises/22_class_template/main.cpp
@@ -1,5 +1,5 @@
 #include "../exercise.h"
-
+#include <cstring>
 // READ: 类模板 <https://zh.cppreference.com/w/cpp/language/class_template>
 
 template<class T>