class A {
public:
    A() {}
    explicit A(const std::string& n):name(n) {}
    const std::string& getName() const {
        return name;
    }
protected:
    std::string name;
};
 
inline
std::ostream& operator<<(std::ostream& os,const A& a) {
    os << a.getName();
    return os;
}
 
class B: public A {
public:
    B():A() {}
    explicit B(const std::string& n):A(n) {}
};
 
inline 
std::ostream& operator<<(std::ostream& os,const B& b) {
    return operator<<(os,static_cast<const A&>(b));
};
 
void abtest()
{
    B dude("mbayabo");
    std::cout << dude << std::endl;
}