// This program implements complex numbers as an abstract data type
// that supports the standard complex binary operations of addition,
// subtraction, multiplication, and division.

#include <iostream.h>
#include <conio.h>

class Complex {
   double real;
   double imag;

public:
   // constructors
   Complex();                // default
   Complex(double);          // only real part given
   Complex(double, double);  // both real and imaginary parts given

   // other methods
   void write()
{
     cout << "\n\n\t";
     cout << "The Complex sum is:  " << real <<
	   " + " << imag << "i" << endl;
}
   // operator methods
   Complex operator+(const Complex) const;
   Complex operator-(const Complex) const;
   Complex operator*(const Complex) const;
   Complex operator/(const Complex) const;
   Complex operator+=(Complex c);
};

// default constructor
Complex::Complex()
{
   real = imag = 0.0;
}

// constructor --real given but not imag
Complex::Complex(double r)
{
   real = r;
   imag = 0.0;
}

// constructor -- real and imag given
Complex::Complex(double r, double i)
{
   real = r;
   imag = i;
}

// Complex + as a binary operator, returns a Complex value
Complex Complex::operator+(const Complex c) const
{
   return Complex(real + c.real, imag + c.imag);
}

// Complex - as a binary operator
Complex Complex::operator-(const Complex c) const
{
   return Complex(real - c.real, imag - c.imag);
}

// Complex * as a binary operator
Complex Complex::operator*(const Complex c) const
{
   return Complex(real * c.real - imag * c.imag,
		  imag * c.real + real * c.imag);
}

Complex Complex::operator/(const Complex c) const
{
   double abs_sq = c.real * c.real + c.imag * c.imag;

   return Complex((real * c.real + imag * c.imag)/abs_sq,
		  (imag * c.real - real * c.imag)/abs_sq);
}
Complex Complex::operator+=(Complex c)
{
  real = real + c.real;
  imag = imag + c.imag;
  return Complex ( real + c.real, imag + c.imag);
}
main()
{
   Complex c1(7.7, 5.5);
   Complex c2(2.2, 3.4);
   Complex c4(10.2, 13.5);
   Complex c3;
   clrscr();
  // c3 = c1 + c2 + c4;    // + for Complex variables
   c3 += c4;
   c3.write();      // write the sum
   getch();         // hold the output screen
   return (0);
}