using System;

struct Complex {
  double re;
  double im;
  
  public Complex(double re, double im) {this.re = re; this.im = im;}
  public Complex(double re) : this(re, 0) {}
  
  public double Re {
    get { return re; }
    set { re = value; }
  }
  
  public double Im {
    get { return im; }
    set { im = value; }
  }
  
  public override string ToString() {
    return String.Format("{0:f2}+{1:f2}i", re, im);
  }
  
  public override bool Equals(object obj) {
    return this == (Complex)obj;
  }
  
  public override int GetHashCode() {
    return ((int)re) ^ ((int)im);
  }
  
  public static Complex operator + (Complex x, Complex y) {
    return new Complex(x.re + y.re, x.im + y.im);
  }
  
  public static Complex operator - (Complex x, Complex y) {
    return new Complex(x.re - y.re, x.im - y.im);
  }
  
  public static Complex operator * (Complex x, Complex y) {
    return new Complex(x.re * y.re - x.im * y.im, x.re * y.im + y.re * x.im);
  }
  
  public static Complex operator / (Complex x, Complex y) {
    double n = y.re * y.re + y.im * y.im;
    return new Complex((x.re * y.re + x.im * y.im)/n, (y.re * x.im - x.re * y.im)/n);
  }
  
  public static bool operator == (Complex x, Complex y) {
    return x.re == y.re && x.im == y.im;
  }
  
  public static bool operator != (Complex x, Complex y) {
    return x.re != y.re || x.im != y.im;
  }
  
  public static explicit operator double(Complex x) {
    return x.re;
  }
  
  public static implicit operator Complex(double x) {
    return new Complex(x, 0);
  }

}

class Test {

  public static void Main() {
    Complex x = 1;
    Complex y = new Complex(2, 1);
    Console.WriteLine(x + y);
    Console.WriteLine(x * y);
    Console.WriteLine(y / y);
    Console.WriteLine((double)y);
  }
}