Eroare de compilare: user.cpp: In function ‘int main()’: user.cpp:5:1: error: ‘ifstream’ was not declared in this scope ifstream f("adunare.in"); ^~~~~~~~ user.cpp:5:1: note: suggested alternative: In file included from /usr/include/c++/6/ios:38:0, from /usr/include/c++/6/ostream:38, from /usr/include/c++/6/iostream:39, from user.cpp:1: /usr/include/c++/6/iosfwd:162:34: note: ‘std::ifstream’ typedef basic_ifstream<char> ifstream; ^~~~~~~~ user.cpp:6:2: error: ‘ofstream’ was not declared in this scope ofstream g("adunare.out"); ^~~~~~~~ user.cpp:6:2: note: suggested alternative: In file included from /usr/include/c++/6/ios:38:0, from /usr/include/c++/6/ostream:38, from /usr/include/c++/6/iostream:39, from user.cpp:1: /usr/include/c++/6/iosfwd:165:34: note: ‘std::ofstream’ typedef basic_ofstream<char> ofstream; ^~~~~~~~ user.cpp:8:8: error: ‘f’ was not declared in this scope f>>a>>b; ^ user.cpp:9:8: error: ‘g’ was not declared in this scope g<<a+b; ^