Eroare de compilare: main.cpp: In function 'int main()': main.cpp:31:4: error: invalid use of non-static member function 'void std::basic_ifstream<_CharT, _Traits>::close() [with _CharT = char; _Traits = std::char_traits<char>]' f.close; ~~^~~~~ In file included from main.cpp:2:0: /usr/include/c++/6/fstream:633:7: note: declared here close() ^~~~~ main.cpp:35:4: error: invalid use of non-static member function 'void std::basic_ofstream<_CharT, _Traits>::close() [with _CharT = char; _Traits = std::char_traits<char>]' g.close; ~~^~~~~ In file included from main.cpp:2:0: /usr/include/c++/6/fstream:839:7: note: declared here close() ^~~~~ Non zero exit status: 1