class Combination:

    def __init__(self, MX=10**6, MOD=998244353):
        self.MX = MX
        self.MOD = MOD
        self.fact = [1] * (MX + 1)
        self.inv = [1] * (MX + 1)
        self.f_inv = [1] * (MX + 1)
        for i in range(2, MX + 1):
            self.fact[i] = (self.fact[i - 1] * i) % self.MOD
            self.inv[i] = ( - (self.MOD // i) * (self.inv[self.MOD % i])) % self.MOD
            self.f_inv[i] = (self.f_inv[i - 1] * self.inv[i]) % self.MOD
    
    def invs(self, n):
        if n <= self.MX:
            return self.inv[n]
        else:
            return pow(n, self.MOD - 2, self.MOD)
    
    def p(self, n, r):
        if r > n or r < 0:
            return 0
        return (self.fact[n] * self.f_inv[r]) % self.MOD
    
    def c(self, n, r):
        if r > n or r < 0:
            return 0
        return (self.fact[n] * self.f_inv[r] * self.f_inv[n - r]) % self.MOD


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

if N == 1:
    ls = [-1, 1, 3, 3, 3, 1, 1]
    print(ls[K])
    exit()

MOD = 998244353
com = Combination()

ans = com.c(2 * N + 4, K)

if K % 2 == 0:
    ans += com.c(N + 2, K // 2) * 2

if N % 2 == 0:
    if K % 2 == 0:
        ans += com.c(N + 2, K // 2)
else:
    if K % 2 == 0:
        ans += com.c(N + 1, K // 2)
        ans += com.c(N + 1, (K - 2) // 2)
    else:
        ans += com.c(N + 1, (K - 1) // 2) * 2

print((ans * com.invs(4)) % MOD)