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