Abstract class

using System;
abstract class car
{
    public int Wheels
    {
        get
        {
            return (4);
        }
    }
    public void Moves()
    {
        Console.WriteLine("moves on the road");
        Console.WriteLine("uses fuel to move");
    }
    public abstract int Doors
    {
        get;
    }
}
class Reva : car
{
    public override int Doors
    {
        get
        {
            return (2);
        }
    }
}
class Demo
{
    static void Main()
    {
        Reva obj = new Reva();
        obj.Moves();
        Console.WriteLine("Number of Wheels:" + obj.Wheels);
        Console.WriteLine("Number of Doors:"  + obj.Doors);
    }
}
Output:
-------
moves on the road
uses fuel to move
Number of Wheels:4
Number of Doors :2