/in/foo.cc: In function 'int main()':
/in/foo.cc:9:2: error: 'cin' was not declared in this scope
  cin>>n;
  ^~~
/in/foo.cc:14:4: error: 'cout' was not declared in this scope
    cout<<" "<<setw(4)<<j*n+i;
    ^~~~
/in/foo.cc:14:21: error: 'setw' was not declared in this scope
    cout<<" "<<setw(4)<<j*n+i;
                     ^
/in/foo.cc:16:3: error: 'cout' was not declared in this scope
   cout<<endl;
   ^~~~
/in/foo.cc:16:9: error: 'endl' was not declared in this scope
   cout<<endl;
         ^~~~