#include <bits/stdc++.h>
using namespace std;
const int N = 23;
const int MOD = 1000000007;
long long f[N], s;
int dp[N];
int n;
int expfast(long long n, int m) {
  int r = 1;
  while (m) {
    if (m & 1) r = r * n % MOD;
    n = n * n % MOD;
    m >>= 1;
  }
  return r;
}
int C(long long n, int k) {
  if (n < k) return 0;
  int ans = 1;
  for (int i = 0; i < k; ++i) ans = ans * ((n - i + MOD) % MOD) % MOD;
  return 1LL * ans * dp[k] % MOD;
}
int main() {
  dp[0] = 1;
  for (int i = 1; i < N; ++i)
    dp[i] = 1LL * dp[i - 1] * expfast(i, MOD - 2) % MOD;
  cin >> n >> s;
  for (int i = 0; i < n; ++i) scanf("%lld", f + i);
  int ans = 0;
  for (int mask = 0; mask < (1 << n); ++mask) {
    long long ss = s;
    for (int j = 0; j < n; ++j)
      if (mask & (1 << j)) ss -= f[j] + 1;
    if (__builtin_popcount(mask) & 1)
      ans = (MOD + ans - C(ss + n - 1, n - 1)) % MOD;
    else
      ans = (ans + C(ss + n - 1, n - 1)) % MOD;
  }
  cout << ans << endl;
  return 0;
}
