diff --git a/basic_content/sizeof/geninhe.cpp b/basic_content/sizeof/geninhe.cpp
index 6ae730e7..5af80a3c 100644
--- a/basic_content/sizeof/geninhe.cpp
+++ b/basic_content/sizeof/geninhe.cpp
@@ -49,7 +49,7 @@ class C {
 class A1 {
   virtual void fun() {}
 };
-class C1 : public A {};
+class C1 : public A1 {};
 
 int main() {
   cout << sizeof(A) << endl; // 8