/in/foo.cc: In member function 'Vector& Vector::operator=(Vector)':
/in/foo.cc:44:16: warning: reference to local variable 'c' returned [-Wreturn-local-addr]
   44 |         return c;
      |                ^
/in/foo.cc:41:34: note: declared here
   41 |         Vector &operator=(Vector c) {
      |                           ~~~~~~~^