import sys
input = lambda :sys.stdin.readline()[:-1]
ni = lambda :int(input())
na = lambda :list(map(int,input().split()))
yes = lambda :print("yes");Yes = lambda :print("Yes");YES = lambda : print("YES")
no = lambda :print("no");No = lambda :print("No");NO = lambda : print("NO")
#######################################################################

mod = 998244353
nn = 1000000
fact = [1] * nn
for i in range(nn - 1):
    fact[i + 1] = fact[i] * (i + 1) % mod
invfact = [1] * nn
invfact[nn - 1] = pow(fact[nn - 1], mod - 2, mod)
for i in range(nn - 1)[::-1]:
    invfact[i] = invfact[i + 1] * (i + 1) % mod
 
def binom(x, y):
    if x < 0 or y < 0 or x - y < 0:
        return 0
    return fact[x] * invfact[y] % mod * invfact[x - y] % mod

n,k = na()
if n == 1:
    print([1,1,3,3,3,1,1][k])
    exit()

if n % 2 == 0 and k % 2 == 0:
    ans = binom(2*n+4, k)+binom(n+2, k//2)*3
elif n % 2 == 0:
    ans = binom(2*n+4,k)
elif k % 2 == 0:
    ans = binom(2*n+4, k)+binom(n+2, k//2)*2+binom(n+1,k//2)+binom(n+1,k//2-1)
else:
    ans = binom(2*n+4, k)+2 * binom(n+1, (k-1)//2)

print(ans * pow(4, mod-2, mod)%mod)