import java.util.*;
import java.lang.*;
import java.io.*;

public class Main {
	public static void main (String[] args) throws java.lang.Exception
	{
		// your code goes here
		// 入力
		Scanner sc = new Scanner(System.in);
		long N = sc.nextLong();
		long L = sc.nextLong();
		long DIV = 998244353L;
		
		// 計算
		long disc = N / L;
		if(N % L != 0){
			disc++;
		}
		
		long ope = myPow(2L, disc, DIV);
		ope--;
		
		// 出力
		System.out.println(ope);
	}
	
	public static long myPow(long x, long n, long m){
		if(n == 0){
			return 1;
		}
		if(n%2 == 0){
			return myPow(x * x % m, n/2, m);
		}else{
			return x * myPow(x, n-1, m) % m;
		}
	}
}