#include<bits/stdc++.h>
using namespace std;
#define int long long
int n,m,a,f[10001][101],s=1;
signed main(){
    cin>>n>>m;
    f[0][0]=1;
    for(int i=1;i<=10000;i++){
        for(int j=0;j<=100;j++) f[i][j]=(f[i][j-1]+f[i-1][j-1])%10007;
    }
    for(int i=1;i<=m;i++){
        cin>>a;
        s*=f[n][a]%10007;
        n-=a;
    }
    cout<<s;
    return 0;
}