using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

/* C# Example of Abstratcion: An application for mobile manufacturing company - Every phone must have to implement caller
 * and sms feature but it depends on company to company (or model to model) if they want to include other features or not
 * which are readily available , you just have to use it without knowing its implementation (like facebook in this example).
 */
namespace AbstractTest
{
    public abstract class feature
    {
        public abstract void Caller();
        public abstract void SMS();
        public void facebook()
        {
            Console.WriteLine("You are using facebook");
        }
    }
    public class Iphone : feature
    {
        public override void Caller()
        {
            Console.WriteLine("iPhone caller feature");
        }
        public override void SMS()
        {
            Console.WriteLine("iPhone sms feature");
        }
        public void otherFeature()
        {
            facebook();
        }
    }
    public class Nokia : feature
    {
        public override void Caller()
        {
            Console.WriteLine("Nokia caller feature");
        }
        public override void SMS()
        {
            Console.WriteLine("Nokia sms feature");
        }
        public void otherFeature()
        {
        }
    }

    class Program
    {
        static void Main(string[] args)
        {
            Iphone c1 = new Iphone();
            c1.Caller();
            c1.SMS();
            c1.otherFeature();
            Nokia n1 = new Nokia();
            n1.Caller();
            n1.SMS();
            n1.otherFeature();
            Console.ReadLine();
        }
    }
}