/in/foo.cc:3:2: error: 'cin' does not name a type
  cin >> n;
  ^~~
/in/foo.cc:4:2: error: expected unqualified-id before 'for'
  for(int i = 1;i < n;i++)
  ^~~
/in/foo.cc:4:16: error: 'i' does not name a type
  for(int i = 1;i < n;i++)
                ^
/in/foo.cc:4:22: error: 'i' does not name a type
  for(int i = 1;i < n;i++)
                      ^
/in/foo.cc:11:2: error: 'cout' does not name a type
  cout << sum << endl;
  ^~~~
/in/foo.cc:12:2: error: expected unqualified-id before 'return'
  return 0;
  ^~~~~~