#include <bits/stdc++.h>
void debug_out() { std::cerr << std::endl; }
template <typename Head, typename... Tail>
void debug_out(Head h, Tail... t) {
  std::cerr << " " << h;
  debug_out(t...);
}
template <typename T1, typename T2>
std::ostream& operator<<(std::ostream& os, std::pair<T1, T2> pa) {
  return os << pa.first << " " << pa.second;
}
template <typename T>
std::ostream& operator<<(std::ostream& os, std::vector<T> vec) {
  for (int i = 0; i < vec.size(); i++)
    os << vec[i] << (i + 1 == vec.size() ? "" : " ");
  return os;
}
template <typename T1, typename T2>
inline bool chmax(T1& a, T2 b) {
  return a < b && (a = b, true);
}
template <typename T1, typename T2>
inline bool chmin(T1& a, T2 b) {
  return a > b && (a = b, true);
}
long long pow_mod(long long a, long long b, long long mod = -1) {
  if (b == 0) return 1;
  if ((a == 0) || (mod != -1 && (a + mod) % mod == 0)) return 0;
  long long x = 1;
  while (b > 0) {
    if (b & 1) x = (mod != -1) ? (x * a) % mod : x * a;
    a = (mod != -1) ? (a * a) % mod : a * a;
    b >>= 1;
  }
  return x;
}
const long long MOD = 1e9 + 7;
using ll = long long;
using P = std::pair<long long, long long>;
int main() {
  std::cin.tie(nullptr);
  std::ios::sync_with_stdio(false);
  ll n, m;
  std::cin >> n >> m;
  std::vector<ll> fib(n + 1, 0);
  fib[1] = 1;
  fib[2] = 1;
  for (long long i = (3); (i) < (n + 1); (i)++)
    fib[i] = (fib[i - 1] + fib[i - 2]) % MOD;
  std::vector<ll> a(m);
  for (long long i = (0); (i) < (m); (i)++) std::cin >> a[i];
  ll ans = 1;
  for (long long i = (0); (i) < (m - 1); (i)++) {
    ans *= fib[a[i + 1] - a[i] - 1];
    ans %= MOD;
  }
  ans *= fib[a[0]];
  ans %= MOD;
  ans *= fib[n - a[m - 1]];
  ans %= MOD;
  std::cout << ans << "\n";
  return 0;
}
