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 Python (3.4.3) (judge verdict: Accepted)

# coding: utf-8
# Your code here!
# coding: utf-8
import sys
sys.setrecursionlimit(10000000)

#const
dxdy=((1,0),(0,1))
# my functions here!
def pin(type=int):
    return map(type,input().rstrip().split())

def resolve():
    t,=pin()
    print(1000*(t//500)+5*((t%500)//5))
"""         
#printデバッグ消した？
#前の問題の結果見てないのに次の問題に行くの？
"""
"""
お前カッコ閉じ,るの忘れてるだろ
"""
import sys
from io import StringIO
import unittest


class TestClass(unittest.TestCase):
    def assertIO(self, input, output):
        stdout, stdin = sys.stdout, sys.stdin
        sys.stdout, sys.stdin = StringIO(), StringIO(input)
        resolve()
        sys.stdout.seek(0)
        out = sys.stdout.read()[:-1]
        sys.stdout, sys.stdin = stdout, stdin
        self.assertEqual(out, output)

    def test_入力例_1(self):
        input = """1024"""
        output = """2020"""
        self.assertIO(input, output)

    def test_入力例_2(self):
        input = """0"""
        output = """0"""
        self.assertIO(input, output)

    def test_入力例_3(self):
        input = """1000000000"""
        output = """2000000000"""
        self.assertIO(input, output)


if __name__ == "__main__":
    resolve()