Eroare de compilare: user.cpp: In function 'int qu(int)': user.cpp:11: warning: operation on 'x' may be undefined user.cpp:11: warning: operation on 'x' may be undefined user.cpp:11: warning: operation on 'x' may be undefined user.cpp:11: warning: operation on 'x' may be undefined user.cpp: In function 'int main()': user.cpp:20: error: reference to 'plus' is ambiguous user.cpp:6: error: candidates are: void plus(int, int) /usr/include/c++/4.2/bits/stl_function.h:134: error: template<class _Tp> struct std::plus user.cpp:20: error: reference to 'plus' is ambiguous user.cpp:6: error: candidates are: void plus(int, int) /usr/include/c++/4.2/bits/stl_function.h:134: error: template<class _Tp> struct std::plus user.cpp:25: error: reference to 'plus' is ambiguous user.cpp:6: error: candidates are: void plus(int, int) /usr/include/c++/4.2/bits/stl_function.h:134: error: template<class _Tp> struct std::plus user.cpp:25: error: reference to 'plus' is ambiguous user.cpp:6: error: candidates are: void plus(int, int) /usr/include/c++/4.2/bits/stl_function.h:134: error: template<class _Tp> struct std::plus