package main

import (
	"fmt"
)

func main() {
	var n, m, div int64
	fmt.Scanf("%d\n%d\n", &n, &m)

	div = n / m

	if div < 1000 {
		fmt.Println(0)
		return
	}

	fmt.Println(div / 1000 * 1000)
}