Eroare de compilare: user.cpp: In function ‘int main()’: user.cpp:5:5: error: ‘ifstream’ was not declared in this scope ifstream cin ("adunare.in"); ^~~~~~~~ user.cpp:5:5: note: suggested alternative: In file included from /usr/include/c++/6/ios:38:0, from /usr/include/c++/6/istream:38, from /usr/include/c++/6/fstream:38, from user.cpp:1: /usr/include/c++/6/iosfwd:162:34: note: ‘std::ifstream’ typedef basic_ifstream<char> ifstream; ^~~~~~~~ user.cpp:6:5: error: ‘ofstream’ was not declared in this scope ofstream cout ("adunare.out"); ^~~~~~~~ user.cpp:6:5: note: suggested alternative: In file included from /usr/include/c++/6/ios:38:0, from /usr/include/c++/6/istream:38, from /usr/include/c++/6/fstream:38, from user.cpp:1: /usr/include/c++/6/iosfwd:165:34: note: ‘std::ofstream’ typedef basic_ofstream<char> ofstream; ^~~~~~~~ user.cpp:7:5: error: ‘cin’ is not a member of ‘std’ std::cin >> a >> b; ^~~ user.cpp:8:5: error: ‘cout’ is not a member of ‘std’ std::cout << a+b; ^~~