using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Insert your customer ID");

        int cID = Convert.ToInt32(Console.ReadLine());

        Console.WriteLine("Insert customer name");

        string cName = Console.ReadLine();

        Console.WriteLine("Insert unit consumed");

        double cUnit = Convert.ToDouble(Console.ReadLine());

​

            if(cUnit <= 199){

            Console.WriteLine("Customer name :"+ cName);

            Console.WriteLine(" Bill is :" + Convert.ToDouble(cUnit*1.20));

            }else  if(cUnit < 400 && cUnit >= 200){

            Console.WriteLine("Customer name :"+ cName);

            Console.WriteLine(" Bill is :" + Convert.ToDouble(cUnit*1.20));

            }

        else  if(cUnit < 600 && cUnit >= 400){

                Console.WriteLine("Customer name :"+ cName);

                Console.WriteLine(" Bill is :" + Convert.ToDouble(cUnit*1.8));

                Console.WriteLine("Surcharge :"+ Convert.ToDouble(0.15*(cUnit*2)));

                Console.WriteLine(" Total Bill is :" + Convert.ToDouble(Convert.ToDouble(cUnit*2)+((cUnit*2)*0.15)));

            }

        else  if(cUnit >= 600){

                Console.WriteLine("Customer name :"+ cName);

                Console.WriteLine(" Bill is :" + Convert.ToDouble(cUnit*2));

                Console.WriteLine("Surcharge :"+ Convert.ToDouble(0.15*(cUnit*2)));

                Console.WriteLine(" Total Bill is :" + Convert.ToDouble(Convert.ToDouble(cUnit*2)+((cUnit*2)*0.15)));

            }

    }

}