Problem:
Score : 100 points

Problem Statement

Snuke has a favorite restaurant.

The price of any meal served at the restaurant is 800 yen (the currency of Japan), and each time a customer orders 15 meals, the restaurant pays 200 yen back to the customer.

So far, Snuke has ordered N meals at the restaurant.
Let the amount of money Snuke has paid to the restaurant be x yen, and let the amount of money the restaurant has paid back to Snuke be y yen.
Find x-y.

Constraints

1 ≤ N ≤ 100

Input

The input is given from Standard Input in the following format:

N

Output

Print the answer.

Sample Input 1

20

Sample Output 1

15800

So far, Snuke has paid 16000 yen, and the restaurant has paid back 200 yen. Thus, the answer is 15800.

Sample Input 2

60

Sample Output 2

47200

Snuke has paid 48000 yen for 60 meals, and the restaurant has paid back 800 yen.

Solution in C# (Mono 4.6.2.0) (judge verdict: Wrong Answer)

using System;
using System.Linq;
using System.Collections.Generic;
using System.IO;
using System.Diagnostics;
using System.Text;

public class Program{
    public static void Main(){
        var watch =  new Stopwatch();
        watch.Start();
        bool istest = true;
        var stream = new StreamWriter(Console.OpenStandardOutput()){AutoFlush = false};
        Console.SetOut(stream);
        TextReader reader;
        string filename="";
        if(filename.Length!=0){
            reader = new StreamReader(filename);
        }else{
            reader = Console.In;
        }

        var n = int.Parse(reader.ReadLine());
        var amr = n>=15 ? n/15*200 : 0;
        Console.WriteLine(amr);
        Console.WriteLine(n*800-amr);
        watch.Stop();
        if(istest){
            Console.WriteLine($"実行時間{watch.ElapsedMilliseconds}ミリ秒");
        }
        Console.Out.Flush();
    }
}