complex numbers cpp implementation

complex.cpp

#include <iostream>
#include <string>


class Complex {
    private:
        double a, b;

    public:
        Complex(){
            a = b = 0;
        }
        Complex(double a){
            this->a = a;
            this->b = 0;
        }
        Complex(double a, double b){
            this->a = a;
            this->b = b;
        }
        /*
        
            Getters

        */
        double real() const { return a; }
        double imag() const { return b; }

        /*

            Setters

        */
        void real(double val) { this->a = val; }
        void imag(double val) { this->b = val; }

        /* 
          
            Operators Overloading
        
        */

        /* Assignment Operator Overloading */
        void operator=(const double a){
            this->a = a;
            this->b = 0;
        }

        void operator=(const Complex& other){
            this->a = other.a;
            this->b = other.b;
        }

        Complex(const char * m_str){
            std::string str = m_str;
            std::size_t space_pos = str.find(" ");
            std::size_t i_pos     = str.find("i");
            if(space_pos != std::string::npos && i_pos != std::string::npos){
                double real = std::stod( str.substr(0, space_pos) );
                double imag = std::stod( str.substr(space_pos + 2, i_pos));
                this->real( real );
                this->imag( imag );            
            }
        }

        /* Sum Operator */
        Complex operator+(const Complex& other){
            return Complex( this->real() + other.real(), this->imag() + other.imag() );
        }

        Complex operator+(const double val){
            return Complex( this->real() + val, this->imag() );
        }

        /* Subtraction Operator */
        Complex operator-(const Complex& other){
            return Complex( this->real() - other.real(), this->imag() - other.imag() );
        }

        Complex operator-(const double val){
            return Complex( this->real() - val, this->imag() );
        }

        /* Multiplication Operator */
        Complex operator*(const Complex& other){
            return Complex( 
                // Real counterpart
                (this->real() * other.real()) - (this->imag() * other.imag()) 
                , 
                // Imaginary counterpart
                (this->real() * other.imag()) + (this->imag() * other.real())
            );
        }

        Complex operator*(const double val){
            return Complex( this->real() * val, this->imag() );
        }

        /* Increment and Decrement Operator */
        Complex operator++(int){
            Complex temp(this->a, this->b);
            temp.real(this->a++);
            return temp;
        }
        
        Complex operator++(){
            Complex temp(this->a, this->b);
            temp.real(++this->a);
            return temp;
        }
        
        Complex operator--(int){
            Complex temp(this->a, this->b);
            temp.real(this->a--);
            return temp;
        }
        
        Complex operator--(){
            Complex temp(this->a, this->b);
            temp.real(--this->a);
            return temp;
        }

        
};

/*

    STREAMS OPERATOR OVERLOADING
    
*/
std::ostream& operator<<(std::ostream& os, const Complex& num){
    os << num.real() << " + " << num.imag() << "i";
    return os;
}

std::istream& operator>>(std::istream& is, Complex& num){
    double a, b;
    is >> a >> b;
    num.real(a);
    num.imag(b);
    return is; 
}


int main(){
    // Constructors
    Complex a;              
    Complex b(1, 2);        
    Complex c(20);          
    Complex d = "3 + 4i";   
    std::cout 
            << "Construtores" << std::endl
            << "a: " << a << std::endl
            << "b: " << b << std::endl
            << "c: " << c << std::endl
            << "d: " << d << std::endl << std::endl;

    // Operations
    std::cout 
            << "Operacoes" << std::endl
            << "a + 4: " << a + 4 << std::endl 
            << "b - 6: " << b - 6 << std::endl 
            << "c * 3: " << c * 3 << std::endl 
            << "d + a: " << d + a << std::endl 
            << "c - b: " << c - b << std::endl 
            << "b * d: " << b * d << std::endl; 

    // Streams
    Complex temp;
    std::cout << "Insira dois reais: ";
    std::cin  >> temp;
    std::cout << "Numero Complexo: " << temp << std::endl; 


}