Mã chấm: 268319

Main.cc: In function ‘int main()’:
Main.cc:11:5: error: ‘cin’ was not declared in this scope
     cin >> n;
     ^~~
Main.cc:11:5: note: suggested alternative:
In file included from Main.cc:4:0:
/usr/include/c++/7/iostream:60:18: note:   ‘std::cin’
   extern istream cin;  /// Linked to standard input
                  ^~~
Main.cc:17:4: error: ‘cout’ was not declared in this scope
    cout <