fn main() {
	let mut s = String::new();
	std::io::stdin().read_line(&mut s).ok();
	let mut d: Vec<i32> = s.trim().split_whitespace()
		.map(|e| e.parse().ok().unwrap()).collect();
	if d[0] == d[1] || 2 * d[0] == d[1] { println!("{}", 4); }
	else if d[0] < d[1] && d[1] < 2 * d[0] { println!("{}", 8); }
	else {println!("{}", 0); }
}