import sys
#import collections as col
input=sys.stdin.readline

def linput(ty=int, cvt=list):
	return cvt(map(ty,input().rstrip().split()))

def vinput(rep=1, ty=int, cvt=list):
	return cvt(ty(input().rstrip()) for _ in "*"*rep)

def facto(x, y, mod):
	re = 1
	for i in range(y, x+1):
		re *= i
		re %= mod
	#print(re, file=sys.stderr)
	return re

def cmb(n, r, mod):
    if ( r<0 or r>n ):
        return 0
    r = min(r, n-r)
    #return facto(n, n-r+1, mod) * g2[r] % mod
    return g1[n] * g2[r] * g2[n-r] % mod

mod = 10**9+7
NN = 10**5+10
g1 = [1, 1] # factorial
g2 = [1, 1] # factorial^(-1)
inverse = [0, 1] # tmp

def init_comb():
    for i in range( 2, NN + 1 ):
        g1.append( ( g1[-1] * i ) % mod )
        inverse.append( ( -inverse[mod % i] * (mod//i) ) % mod )
        g2.append( (g2[-1] * inverse[-1]) % mod )


def main():
	A,B = linput()
	M = mod
	
	res = cmb(B+1, A+1, M)
	print(res)

def solve():
	N,L = linput()
	res = 0
	
	M = -(-N//L)
	mod = 998244353
	res = pow(2, M, mod) - 1
	res %= mod
	
	print(res)
	
	
solve()

#init_comb()
#main()