fn main() {
    let mut n = String::new();
    std::io::stdin().read_line(&mut n).ok();
    let n: usize = n.trim().parse().unwrap();

    let result = (0..60).rev().filter(|&i| ((n >> i) & 1) == 1).map(|i| 1usize << i).nth(0).unwrap();
    println!("{}", result);
}