How to Declare Structure and Assign the Value and Call in C#

using System.IO;
using System;
class Complex
{
    public int x;
    public int y;
}
struct Real
{
    public int x;
    public int y;
}
class StructureAndClassAssignment
{
    static void Main(string[] args)
    {
        Complex complexNumber1 = new Complex();
        complexNumber1.x = 10;
        complexNumber1.y = 20;
        Complex complexNumber2 = complexNumber1;
        complexNumber1.x = 1000;
        complexNumber1.y = 2000;
        Console.WriteLine("Class: x:{0}, y:{1}", complexNumber2.x, complexNumber2.y);
        Real realNumber1 = new Real();
        realNumber1.x = 100;
        realNumber1.y = 200;
        Real realNumber2 = realNumber1;
        realNumber1.x = 10;
        realNumber1.y = 20;
        Console.WriteLine("Struct: x:{0}, y:{1}", realNumber2.x, realNumber2.y);
    }
}