package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
)

func main() {
	N := nextLong()
	M := nextLong()

	ans := N / (1000 * M) * 1000
	fmt.Println(ans)
}

var sc = bufio.NewScanner(os.Stdin)

func next() string {
	sc.Split(bufio.ScanWords)
	sc.Scan()
	return sc.Text()
}

func nextLong() int64 {
	i, e := strconv.ParseInt(next(), 10, 64)
	if e != nil {
		panic(e)
	}
	return i
}