1
UserProfile\main.cpp|9|undefined reference to `UserProfile::levelabi:cxx11 const’|
将>>和<<运算符重载放在UserProfile.cpp里，在main.cpp申明重载即可
main.cpp
ostream& operator<<( ostream &os, const UserProfile &rhs );
istream& operator>>( istream &is, UserProfile &rhs );
2
UserProfile\main.cpp|21|undefined reference to `UserProfile::UserProfile(std::__cxx11::basic_string<char, std::char_traits, std::allocator >, UserProfile::uLevel)’|
将构造函数放在UserProfile.h
class{
};
inline UserProfile::UserProfile(string login,uLevel level)
:_login(login),_user_level(level),_times_logged(1),_guesses(0),_correct_guesses(0)
{
}