fn main() {
	let mut s = String::new();
	std::io::stdin().read_line(&mut s).ok();
	let n: Vec<u64> = s.split_whitespace().flat_map(str::parse).collect();
	let m = n[0] / n[1] + if n[0] % n[1] == 0 { 0 } else { 1 };
	let mut a = 2;
	for _ in 1..m {
		a = a * 2 % 998244353;
	}
	println!("{}", a - 1)
}