#include <bits/stdc++.h>
using namespace std;

template <int mod = (int)(998244353)>
struct ModInt {
  int x;
  ModInt() : x(0) {}
  ModInt(int64_t y)
      : x(y >= 0 ? y % mod : (mod - (-y) % mod) % mod) {}
  ModInt &operator+=(const ModInt &p) {
    if((x += p.x) >= mod) x -= mod;
    return *this;
  }
  ModInt &operator-=(const ModInt &p) {
    if((x += mod - p.x) >= mod) x -= mod;
    return *this;
  }
  ModInt &operator*=(const ModInt &p) {
    x = (int)(1LL * x * p.x % mod);
    return *this;
  }
  ModInt &operator/=(const ModInt &p) {
    *this *= p.inverse();
    return *this;
  }
  ModInt operator-() const { return ModInt(-x); }
  ModInt operator+(const ModInt &p) const {
    return ModInt(*this) += p;
  }
  ModInt operator-(const ModInt &p) const {
    return ModInt(*this) -= p;
  }
  ModInt operator*(const ModInt &p) const {
    return ModInt(*this) *= p;
  }
  ModInt operator/(const ModInt &p) const {
    return ModInt(*this) /= p;
  }
  bool operator==(const ModInt &p) const {
    return x == p.x;
  }
  bool operator!=(const ModInt &p) const {
    return x != p.x;
  }
  ModInt inverse() const {
    int a = x, b = mod, u = 1, v = 0, t;
    while(b > 0) {
      t = a / b;
      swap(a -= t * b, b);
      swap(u -= t * v, v);
    }
    return ModInt(u);
  }
  ModInt pow(int64_t n) const {
    ModInt res(1), mul(x);
    while(n) {
      if(n & 1) res *= mul;
      mul *= mul;
      n >>= 1;
    }
    return res;
  }
  friend ostream &operator<<(ostream &os, const ModInt &p) {
    return os << p.x;
  }
  friend istream &operator>>(istream &is, ModInt &a) {
    int64_t t;
    is >> t;
    a = ModInt<mod>(t);
    return (is);
  }
  static int get_mod() { return mod; }
};

struct Combination {
  vector<ModInt<>> _fact, _rfact, _inv;
  Combination(long long nsize = 5000000)
      : _fact(nsize + 1), _rfact(nsize + 1),
        _inv(nsize + 1) {
    _fact[0] = _rfact[nsize] = _inv[0] = 1;
    for(int i = 1; i <= nsize; i++)
      _fact[i] = _fact[i - 1] * i;
    _rfact[nsize] /= _fact[nsize];
    for(int i = nsize - 1; i >= 0; i--)
      _rfact[i] = _rfact[i + 1] * (i + 1);
    for(int i = 1; i <= nsize; i++)
      _inv[i] = _rfact[i] * _fact[i - 1];
  }
  inline ModInt<> fact(int k) const { return _fact[k]; }

  inline ModInt<> rfact(int k) const { return _rfact[k]; }

  inline ModInt<> inv(int k) const { return _inv[k]; }

  ModInt<> P(int n, int r) const {
    if(r < 0 || n < r) return 0;
    return fact(n) * rfact(n - r);
  }

  ModInt<> C(int p, int q) const {
    if(q < 0 || p < q) return 0;
    return fact(p) * rfact(q) * rfact(p - q);
  }
  ModInt<> H(int n, int r) const {
    if(n < 0 || r < 0) return (0);
    return r == 0 ? 0 : C(n + r - 1, r - 1);
  }
};

long long n, s;
vector<long long> a;
vector<vector<ModInt<>>> dp;

ModInt<> solve();

int main() {
  cin >> n >> s;
  a.resize(n);
  for(int i = 0; i < n; ++i) cin >> a[i];
  cout << solve() << endl;
  return 0;
}

ModInt<> solve() {
  ModInt<> res = 0;
  dp.assign(n + 1, vector<ModInt<>>(s + 1, 0));
  dp[0][0] = 1;
  for(int i = 0; i < n; ++i)
    for(int j = 0; j <= s; ++j) {
      if(j != s) dp[i + 1][j] += dp[i][j];
      if(j >= a[i]) {
        if(j == a[i])
          dp[i + 1][j] += i + 1;
        else
          dp[i + 1][j] += dp[i][j - a[i]];
        if(s == j) res += dp[i + 1][j] * (n - i);
      }
    }
  return res;
}

Measured memory_bytes: 35584