/in/foo.cc: In function 'int main()':
/in/foo.cc:12:2: error: 'cin' was not declared in this scope
  cin >> n;
  ^~~
/in/foo.cc:13:2: error: 'cout' was not declared in this scope
  cout << wow(n) << endl;
  ^~~~
/in/foo.cc:13:20: error: 'endl' was not declared in this scope
  cout << wow(n) << endl;
                    ^~~~