Problem:
Score : 200 points

Problem Statement

Takahashi loves gold coins. He gains 1000 happiness points for each 500-yen coin he has and gains 5 happiness points for each 5-yen coin he has. (Yen is the currency of Japan.)

Takahashi has X yen. If he exchanges his money so that he will gain the most happiness points, how many happiness points will he earn?

(We assume that there are six kinds of coins available: 500-yen, 100-yen, 50-yen, 10-yen, 5-yen, and 1-yen coins.)

Constraints

0 \leq X \leq 10^9

X is an integer.

Input

Input is given from Standard Input in the following format:

X

Output

Print the maximum number of happiness points that can be earned.

Sample Input 1

1024

Sample Output 1

2020

By exchanging his money so that he gets two 500-yen coins and four 5-yen coins, he gains 2020 happiness points, which is the maximum number of happiness points that can be earned.

Sample Input 2

0

Sample Output 2

0

He is penniless - or yenless.

Sample Input 3

1000000000

Sample Output 3

2000000000

He is a billionaire - in yen.

Solution in Scala (2.11.7) (judge verdict: Accepted)

object Main extends App {
  for(line <- io.Source.stdin.getLines()) {
    val numAry = line.split(' ').map { _.toInt }
    val _money = numAry(0).toInt
    val money = if ((0 <= _money) && (_money <= 1000000000)) _money else 0

    val coinNum500: Int = money/500
    val coinNum5: Int = (money - coinNum500*500)/5
    val hpns500: Int = coinNum500*1000
    val hpns5: Int = coinNum5*5
    val hapiness = hpns500 + hpns5
    println(hapiness)
  }
}