package main

import (
	"bufio"
	"fmt"
	"io"
	"os"
)

var modVar = int64(1e9) + int64(7)

func solve(in io.Reader, out, err io.Writer) {
	budget, num := int64(0), int64(0)
	fmt.Fscan(in, &budget, &num)
	fmt.Fprintln(out, ((budget/int64(1000))/num)*1000)
}

func main() {
	br := bufio.NewReaderSize(os.Stdin, int(1e4))
	solve(br, os.Stdout, os.Stderr)
}