#include <bits/stdc++.h>
using namespace std;
const int N = 22;
const int base = 1E9 + 7;
int n, ans;
long long a[N], m;
int fact[N], inv[N];
void Read_Input() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  cin >> n >> m;
  for (int i = 0; i < n; i++) cin >> a[i];
}
int Power(int a, int b) {
  int mul = a, ret = 1;
  while (b > 0) {
    if (b & 1) ret = (long long)ret * mul % base;
    mul = (long long)mul * mul % base;
    b >>= 1;
  }
  return ret;
}
void Init() {
  fact[0] = 1;
  for (int i = 1; i <= n; i++) fact[i] = (long long)fact[i - 1] * i % base;
  inv[n] = Power(fact[n], base - 2);
  for (int i = n - 1; i >= 0; i--)
    inv[i] = (long long)inv[i + 1] * (i + 1) % base;
}
int Ckn(int k, long long n) {
  long long tu = 1;
  if (k > n || k < 0 || n < 0) return 0;
  for (int i = 1; i <= k; i++) tu = (long long)tu * ((n - k + i) % base) % base;
  return (long long)tu * inv[k] % base;
}
void Try(int i, int cnt, long long S) {
  if (i >= n) {
    if (cnt & 1)
      ans = (ans - Ckn(n - 1, m - S + n - 1) + base) % base;
    else
      ans = (ans + Ckn(n - 1, m - S + n - 1)) % base;
    return;
  }
  Try(i + 1, cnt, S);
  Try(i + 1, cnt + 1, S + a[i] + 1);
}
int main() {
  Read_Input();
  Init();
  Try(0, 0, 0);
  cout << ans;
  return 0;
}
