#include <bits/stdc++.h>
using namespace std;
using ll = long long;
template <class T, class U>
using Pa = pair<T, U>;
template <class T>
using vec = vector<T>;
template <class T>
using vvec = vector<vec<T>>;
constexpr ll mod = 998244353;
struct mint {
  ll x;
  mint(ll x = 0) : x((x % mod + mod) % mod) {}
  friend ostream& operator<<(ostream& os, const mint& a) { return os << a.x; }
  friend istream& operator>>(istream& is, mint& a) {
    ll t;
    is >> t;
    a = mint(t);
    return (is);
  }
  mint& operator+=(const mint a) {
    if ((x += a.x) >= mod) x -= mod;
    return *this;
  }
  mint& operator-=(const mint a) {
    if ((x += mod - a.x) >= mod) x -= mod;
    return *this;
  }
  mint& operator*=(const mint a) {
    (x *= a.x) %= mod;
    return *this;
  }
  mint operator+(const mint a) const {
    mint res(*this);
    return res += a;
  }
  mint operator-(const mint a) const {
    mint res(*this);
    return res -= a;
  }
  mint operator*(const mint a) const {
    mint res(*this);
    return res *= a;
  }
  mint pow(ll t) const {
    if (!t) return 1;
    mint a = pow(t >> 1);
    a *= a;
    if (t & 1) a *= *this;
    return a;
  }
  mint inv() const { return pow(mod - 2); }
  mint& operator/=(const mint a) { return (*this) *= a.inv(); }
  mint operator/(const mint a) const {
    mint res(*this);
    return res /= a;
  }
};
int main() {
  cin.tie(0);
  ios::sync_with_stdio(false);
  int N, S;
  cin >> N >> S;
  vec<int> A(N);
  for (int i = 0; i < N; i++) cin >> A[i];
  vvec<mint> dp(N + 1, vec<mint>(S + 1));
  mint ans = 0;
  for (int i = 0; i < N; i++) {
    if (S < A[i]) continue;
    dp[i + 1][A[i]] += i + 1;
    for (int j = 1; j < S; j++) {
      dp[i + 1][j] += dp[i][j];
      if (j + A[i] <= S) dp[i + 1][j + A[i]] += dp[i][j];
    }
  }
  for (int i = 1; i <= N; i++) ans += dp[i][S] * (N - i + 1);
  cout << ans << "\n";
}
