/in/foo.cc:2:9: error: 'cin' does not name a type
    2 |         cin>>x;
      |         ^~~
/in/foo.cc:3:9: error: expected unqualified-id before 'while'
    3 |         while(x)
      |         ^~~~~
/in/foo.cc:8:9: error: 'cout' does not name a type
    8 |         cout<<y;
      |         ^~~~