<!DOCTYPE html>
<html>

  <script>
    'use strict';

    // define Complex type objects
    function Complex(a, b)
    {
        // construct a Complex number..
        this.re = a;
        this.imag = b;


        // display function:
        this.show = function ()
        {
            if (this.imag < 0)
                document.writeln(this.re + " " + this.imag + "i <br>");

            else
                document.writeln(this.re + " + " + this.imag + "i <br>");
        };

        // add
        this.add = function (other)
        {
            return new Complex(this.re + other.re, this.imag + other.imag);
        };

        // subtract
        this.sub = function (other)
        {
            return new Complex(this.re - other.re, this.imag - other.imag);
        };

        // multiply
        this.mult = function (other)
        {
            return new Complex(this.re * other.re - this.imag * other.imag, this.re * other.imag + this.imag * other.re);
        };

        this.div = function (other)
        {
            var denom = other.re * other.re + other.imag * other.imag;
            var real = this.re * other.re + this.imag * other.imag;
            var im = this.imag * other.re - this.re * other.imag;
            return new Complex(real / denom, im / denom);
        };

    }



    var c1 = new Complex(2, 1);
    var c2 = new Complex(0, 1);
    var c3 = c1.add(c2);
    c3.show();
  </script>
  <head>
    <title>Complex</title>
  </head>
  <body>
  </body>
</html>