use std::io;

fn main() {
    let mut line = String::new();

    io::stdin().read_line(&mut line).unwrap();
    let n: i64 = line.trim().parse().unwrap();

    line.clear();
    io::stdin().read_line(&mut line).unwrap();
    let m: i64 = line.trim().parse().unwrap();

    println!("{}", ((n / 1000) / m) * 1000);
}