/in/foo.cc: In function 'int main()':
/in/foo.cc:3:5: error: 'cin' was not declared in this scope
     cin >> m >> n;
     ^~~
/in/foo.cc:9:13: error: 'cout' was not declared in this scope
             cout << " ";
             ^~~~
/in/foo.cc:12:13: error: 'cout' was not declared in this scope
             cout << "*";
             ^~~~
/in/foo.cc:16:17: error: 'cout' was not declared in this scope
                 cout << " ";
                 ^~~~
/in/foo.cc:19:17: error: 'cout' was not declared in this scope
                 cout << "*";
                 ^~~~
/in/foo.cc:22:9: error: 'cout' was not declared in this scope
         cout << endl;
         ^~~~
/in/foo.cc:22:17: error: 'endl' was not declared in this scope
         cout << endl;
                 ^~~~