@@ -10,6 +10,7 @@
     1.  [goto crosses initialization of](goto-cross-initialization.cpp)
     1.  [const](const.cpp)
     1.  [enum](enum.cpp)
+        1.  [enum_signed.cpp](enum_signed.cpp)
     1.  [RTTI](rtti.md)
     1.  [Value category](value_category.cpp)
     1.  Compile time magic
 
@@ -0,0 +1,15 @@
+// https://stackoverflow.com/questions/159034/are-c-enums-signed-or-unsigned/54572423#54572423
+
+#include <cassert>
+#include <iostream>
+#include <type_traits>
+
+enum Unscoped {};
+enum class ScopedDefault {};
+enum class ScopedExplicit : long {};
+
+int main() {
+    std::cout << std::is_signed<std::underlying_type<Unscoped>>() << std::endl;
+    assert((std::is_same<std::underlying_type<ScopedDefault>::type, int>()));
+    assert((std::is_same<std::underlying_type<ScopedExplicit>::type, long>()));
+}