#include <iostream>
#include <fstream>
#define MOD 1000003
using namespace std;
ifstream f("grigo.in");
ofstream g("grigo.out");
int s[100003];
void solve()
{
    int n,m,i,x; f>>n>>m;
    for(i=1;i<=m;i++){f>>x; s[i]=1;}
    for(i=2;i<=n;i++)if(s[i]==1)s[i]=s[i-1]; else s[i]=((i-1)*s[i-1])%MOD;
    g<<s[n];
}
int main()
{
    solve();
    return 0;
}