MOD = 998244353

c, x = map(int, input().split())

if x == 0:
    print(pow(c + 1, MOD - 2, MOD))
    exit()

dp = [0] * (x + 1)
dp[0] = 1
for i in range(c + 1, x + 1):
    ndp = [0] * (x + 1)
    inv = pow(i, MOD - 2, MOD)
    for j in range(x):
        ndp[j] += dp[j] * (j * inv % MOD)
        ndp[j] %= MOD
        ndp[j + 1] += dp[j] * ((i - j) * inv % MOD)
        ndp[j + 1] %= MOD
    dp = ndp

ans = 0
for i, d in enumerate(dp):    
    ans += d * (1 - pow(x + 1 - i, MOD - 2, MOD)) % MOD
    ans %= MOD

print(ans)