#include <bits/stdc++.h>
#define nx 11000
using namespace std;
typedef long long ll;
ll n,m;
ll a[nx];
ll res[nx][nx];
const int x = 10007;
int C(ll a,ll b){
	if(b==0||b==a){
		return 1;
	}
	if(res[a][b]!=0){
		return res[a][b];
	}
	return res[a][b]=(C(a-1,b-1)+C(a-1,b));
}
int main(){
	cin>>n>>m;
	for(ll i = 0;i<m;++i){
		cin>>a[i];
	}
	ll sum = 1;
	for(ll i = 0;i<m;++i){
		sum*=C(n,a[i]);
		sum%=x;
		n-=a[i];
	}
	cout<<sum;
	return 0;
}