using System;

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Input Item");

        int c = 3000;//Convert.ToInt32(Console.ReadLine());

        Console.WriteLine("Your Input : " + c);

        Console.WriteLine("Result : " + calculate(c));

    }

    private static double calculate (int item)

    {

        double sum = 0;

        int count = 0;

        for(int i = 0 ; i< item ;i++)

        {

            count++;

            switch(count < 201? "A" : 

                  count < 501? "B" : 

                  count < 1001? "C" : 

                  count < 1501? "D" : "E")

            {

                case "A" : sum = sum + 200;

                    break;

                case "B" : sum = sum + (200 - (200*0.03));

                    break;

                case "C" : sum = sum + (200 - (200*0.05));

                    break;

                case "D" : sum = sum + (200 - (200*0.075));

                    break;

                case "E" : sum = sum + (200 - (200*0.10));

                    break;      

            } 

        }

        return sum;

    }

}