n, m = map(int, input().split())
A = list(map(int, input().split()))
mod = 998244353

fact = [1] * (m + 1)
inv = [1] * (m + 1)
finv = [1] * (m + 1)
for i in range(2, m + 1):
    fact[i] = fact[i - 1] * i % mod
    inv[i] = mod - inv[mod % i] * (mod // i) % mod
    finv[i] = finv[i - 1] * inv[i] % mod

def comb(a, b):
    return fact[a] * finv[b] * finv[a - b] % mod

dp = [0 for _ in range(m + 1)]
stones = [0 for _ in range(m + 1)]
dp[0] = 1
for i in range(m):
    if dp[i] > 0:
        for j in range(n):
            if i + A[j] > m:
                continue
            if stones[i + A[j]] != 0 and stones[i] + 1 > stones[i + A[j]]:
                continue
            stones[i + A[j]] = stones[i] + 1
            dp[i + A[j]] = comb(m - stones[i + A[j]], i + A[j] - stones[i + A[j]])

ans = 0
for i in range(m + 1):
    ans += dp[i]
    ans %= mod
print(ans)