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 divisor(n):
    ans = []
    for i in range(1, int(n**0.5)+1):
        if n % i == 0:
            ans.append(i)
            if i*i != n:
                ans.append(n//i)
    return ans

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

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

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

M = abs(M)

if M == 0:
    if N%2 == 0:
        a = cp.C(N, N//2)*pow(2, N, MOD)%MOD*2%MOD
        b = cp.C(N, N//2)**2%MOD
        a -= b
        a %= MOD
        print(inverse(a, pow(4, N, MOD)))
    else:
        print(0)
    exit()

div = divisor(M)
SUM = 0
for d in div:
    if N%2 == d%2 and N%2 == M//d%2 and d <= N and M//d <= N:
        SUM += cp.C(N, d+(N-d)//2)*cp.C(N, (M//d)+(N-(M//d))//2)%MOD*2%MOD
        SUM %= MOD

print(inverse(SUM, pow(4, N, MOD)))