#ifndef _COMPLEX_H_ #define _COMPLEX_H_ #include namespace complex { class Complex { public: // Should the assignment operator return a reference? // (Answer: ?) Complex &operator=(const Complex &a) { if (this != &a) { this->real_ = a.real_; this->imag_ = a.imag_; } return *this; } private: double real_, imag_; }; // class Complex } // namespace complex #endif // _COMPLEX_H_