#include <bits/stdc++.h>
#pragma gcc optimize("ofast")
using namespace std;
bool prime(long long n) {
  if (n <= 1) return false;
  if (n <= 3) return true;
  if (n % 2 == 0 || n % 3 == 0) return false;
  for (long long i = 5; i * i <= n; i += 6) {
    if (n % i == 0 || n % (i + 2) == 0) return false;
  }
  return true;
}
long long modexp(long long a, long long b, long long m) {
  long long r = 1;
  a = a % m;
  while (b > 0) {
    if (b & 1) r = (r * a) % m;
    b = b >> 1;
    a = (a * a) % m;
  }
  return r % m;
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  long long n, s;
  cin >> n >> s;
  vector<long long> arr(n);
  for (int i = 0; i < n; i++) cin >> arr[i];
  vector<long long> dp(s + 1);
  long long ans = 0;
  for (int i = 0; i < n; i++) {
    dp[0]++;
    for (long long j = s; j >= arr[i]; j--) {
      dp[j] = (dp[j] + dp[j - arr[i]]) % 1000000007;
    }
    ans = (ans + dp[s]) % 1000000007;
  }
  cout << ans;
  return 0;
}
