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)

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

MOD = 998244353

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

if N == 1:
    if M%2 == 1:
        print(M//2)
    else:
        print(inverse(M//2*2-1, 2))
    exit()

ans = 0
cp = CP(10**6*3)
for MIN in range(1, M):
    r = M-MIN*N
    if r < 0:
        break
    cnt = cp.H(N+1, r)
    if (MIN+1)*N <= M:
        r = M-(MIN+1)*N
        cnt -= cp.H(N+1, r)
        cnt %= MOD
    ans += MIN*cnt
    ans %= MOD

print(inverse(ans, (cp.H(N+1, M)-N)%MOD))