Eroare de compilare: user.cpp: In member function ‘Tree::Query& Tree::Query::operator=(const Tree::Query&)’: user.cpp:42: instantiated from ‘void std::vector<_Tp, _Alloc>::_M_insert_aux(__gnu_cxx::__normal_iterator<typename std::_Vector_base<_Tp, _Alloc>::_Tp_alloc_type::pointer, std::vector<_Tp, _Alloc> >, const _Tp&) [with _Tp = Tree::Query, _Alloc = std::allocator<Tree::Query>]’ /usr/include/c++/4.4/bits/stl_vector.h:741: instantiated from ‘void std::vector<_Tp, _Alloc>::push_back(const _Tp&) [with _Tp = Tree::Query, _Alloc = std::allocator<Tree::Query>]’ user.cpp:30: instantiated from here user.cpp:42: error: non-static reference member ‘int& Tree::Query::answer_’, can't use default assignment operator In file included from /usr/include/c++/4.4/vector:69, from user.cpp:2: /usr/include/c++/4.4/bits/vector.tcc: In member function ‘void std::vector<_Tp, _Alloc>::_M_insert_aux(__gnu_cxx::__normal_iterator<typename std::_Vector_base<_Tp, _Alloc>::_Tp_alloc_type::pointer, std::vector<_Tp, _Alloc> >, const _Tp&) [with _Tp = Tree::Query, _Alloc = std::allocator<Tree::Query>]’: /usr/include/c++/4.4/bits/vector.tcc:312: note: synthesized method ‘Tree::Query& Tree::Query::operator=(const Tree::Query&)’ first required here