using System;

public class Program

{

    public class Base

    {

        public int Property {get; set;}

    }

    public class Derived: Base

    {

        public new int Property {get; set;}

    }

    public static void Main()

    {

        var val = new Derived();

        val.Property = 1;

        Console.WriteLine(val.Property);

        PrintBase(val);

    }

    public static void PrintBase(Base val)

    {

        Console.WriteLine(val.Property);

    }

}