N, M = map(int, input().split())
mod = 998244353
dp = [0] * (M + 1)
dp[0] = 1
for i in range(M):
    dp[i + 1] += dp[i]
    dp[i + 1] %= mod
    if i + N <= M and N != 1:
        dp[i + N] += dp[i]
        dp[i + N] %= mod
print(dp[-1])