class CP:
    def __init__(self, N):
        self.fact = [1]*(N+1)
        self.fact_inv = [1]*(N+1)
        for i in range(2, N+1):
            self.fact[i] = self.fact[i-1]*i%MOD
        self.fact_inv[N] = pow(self.fact[N], -1, MOD)
        for i in reversed(range(1, N)):
            self.fact_inv[i] = self.fact_inv[i+1]*(i+1)%MOD
    def C(self, N, K):
        if N < 0 or K < 0 or N < K:
            return 0
        return self.fact[N]*self.fact_inv[K]%MOD*self.fact_inv[N-K]%MOD
    def P(self, N, K):
        if N < 0 or K < 0 or N < K:
            return 0
        return self.fact[N]*self.fact_inv[N-K]%MOD
    def H(self, N, K):
        if N < 0 or K < 0:
            return 0
        if N == K == 0: return 1
        return self.C(N+K-1, K)

def inverse(n, d):
    return n * pow(d, -1, MOD) % MOD

MOD = 998244353
cp = CP(10**6)

N, K = map(int, input().split())

if N == 1:
    if K == 1:
        print(1)
    elif K == 2:
        print(3)
    elif K == 3:
        print(4)
    elif K == 4:
        print(3)
    elif K == 5:
        print(1)
    else:
        print(1)
    exit()

C = N+2

ans1 = cp.C(C*2, K)
ans2 = 0
if K%2 == 0:
    ans2 = cp.C(C, K//2)
ans3 = 0
if N%2 == 1:
    if K%2 == 0:
        ans3 = (cp.C((N//2+1)*2, K//2)+cp.C((N//2+1)*2, (K-2)//2))%MOD
    else:
        ans3 = cp.C((N//2+1)*2, (K-1)//2)*2%MOD
else:
    if K%2 == 0:
        ans3 = cp.C((N//2+1)*2, K//2)
ans4 = 0
if K%2 == 0:
    ans4 = cp.C(C, K//2)

print(inverse((ans1+ans2+ans3+ans4)%MOD, 4))