#include <bits/stdc++.h>
const long long mod = 1e9 + 7;
long long ans = 0, s, f[30];
int n;
long long moc(long long x) { return x < mod ? x : x - mod; }
long long mpow(long long a, long long b) {
  long long c = 1;
  for (; b; b >>= 1, a = a * a % mod) {
    if (b & 1) c = c * a % mod;
  }
  return c;
}
long long comb(long long n, long long m) {
  if (n - m < m) {
    m = n - m;
    if (m < 0) return 0;
  }
  long long a = 1, b = 1;
  for (long long i = 1; i <= m; i++) {
    b = b * i % mod;
    a = a * (n - i + 1) % mod;
  }
  return a * mpow(b, mod - 2) % mod;
}
long long lucas(long long n, long long m) {
  if (n <= mod && m <= mod) return comb(n, m);
  return comb(n % mod, m % mod) * lucas(n / mod, m / mod) % mod;
}
void rchi(int step, int tot, long long res) {
  if (res < 0) return;
  if (step > n) {
    if (tot & 1)
      ans = moc(mod + ans - lucas(res + n - 1, n - 1));
    else
      ans = moc(ans + lucas(res + n - 1, n - 1));
    return;
  }
  rchi(step + 1, tot, res);
  rchi(step + 1, tot + 1, res - f[step] - 1);
}
int main() {
  while (~scanf("%d%lld", &n, &s)) {
    ans = 0;
    for (int i = 1; i <= n; i++) {
      scanf("%lld", &f[i]);
    }
    rchi(1, 0, s);
    printf("%lld", ans);
  }
  return 0;
}
