#include <bits/stdc++.h>
using namespace std;
const int mod = 998244353;
int main() {
  int n, s;
  cin >> n >> s;
  int a[n + 1], dp[n + 1][s + 1];
  for (int i = 1; i <= n; i++) cin >> a[i];
  memset(dp, 0, sizeof(dp));
  int ans = 0;
  for (int i = 1; i <= n; i++) {
    for (int j = 1; j <= s; j++) {
      dp[i][j] += dp[i - 1][j];
      dp[i][j] %= mod;
    }
    dp[i][a[i]] += i;
    dp[i][a[i]] %= mod;
    for (int j = a[i]; j <= s; j++) {
      dp[i][j] += dp[i - 1][j - a[i]];
      dp[i][j] %= mod;
    }
    ans += dp[i][s];
    ans %= mod;
  }
  cout << ans << endl;
  return 0;
}
