MOD = 998244353

n, m = map(int, input().split())
if n == 1:
    print(1)
    exit()
dp = [1] * (m + 1)
for i in range(n, m + 1):
    dp[i] = dp[i - 1] + dp[i - n]
    dp[i] %= MOD

print(dp[-1])