#include <bits/stdc++.h>
#define int long long
using namespace std;
int p = 1e9 + 7;
int ji[100];
int f(int x)
{
    if (x < 0)
    {
        cout << 0;
        exit(0);
    }
    int ans = 0;
    while (x)
    {
        if (x % 2 == 1)
            ans++;
        x /= 2;
    }
    return ji[ans];
}
signed main()
{
   
    ji[0] = 1;
    for (int i = 1; i <= 62; i++)
    {
        ji[i] = ji[i - 1] * i % p;
        ji[i] = ji[i] % p;
    }
    int n, t;
    cin >> n >> t;
    int ans = 1;
    int hh;
    int s = 0;
    for (int i = 1; i <= t; i++)
    {
        cin >> hh;
        ans = ans * f(hh - s);
        ans = ans % p;
        s = hh;
    }
    ans = ans * f(pow(2, n) - 1 - s);
    ans = ans % p;
    cout << ans;
    return 0;
}