#include <bits/stdc++.h>
using namespace std;
const long long Mod = 1e9 + 7;
template <typename T>
static T mod(T a, T m) {
  a %= m;
  if (a < 0) a += m;
  return a;
}
template <typename T>
static T inverse(T a, T m) {
  a = mod(a, m);
  if (a == 1) return a;
  return mod((1 - inverse(m, a) * m) / a, m);
}
long long ncr(long long n, long long r) {
  long long ret = 1;
  for (long long i = 1; i <= r; i++) {
    ret = ret * ((n - i + 1) % Mod);
    ret = mod(ret, Mod);
    ret = ret * inverse(i, Mod);
    ret = mod(ret, Mod);
  }
  return ret;
}
int main() {
  long long n, s, f[20];
  cin >> n >> s;
  for (long long i = 0; i < n; i++) {
    cin >> f[i];
  }
  long long ans = 0;
  for (long long i = 0; i < (1 << n); i++) {
    long long bp = __builtin_popcount(i);
    long long sum = s;
    for (long long j = 0; j < n; j++) {
      if (i & (1 << j)) {
        sum -= (f[j] + 1);
      }
    }
    if (sum < 0) continue;
    if (bp % 2 == 0) {
      ans += ncr(sum + n - 1, n - 1);
      ans = mod(ans, Mod);
    } else {
      ans -= ncr(sum + n - 1, n - 1);
      ans = mod(ans, Mod);
    }
  }
  cout << ans << endl;
  return 0;
}
