import java.util.Arrays;
import java.util.Scanner;

public class N016 {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		long x=sc.nextLong(),n=sc.nextLong();
		long[] a=new long[(int)n];
		for(long i=0;i<n;i++){
			a[(int)i]=sc.nextLong();
		}
		Arrays.sort(a);
		long mem=1;
		long cnt=0;
		long ans=0;
		long beki=(int)Math.pow(10, 6)+3;
		long buf=(int)Math.pow(2, 20)%beki;
		for(int i=0;i<n;i++){
			long dif=a[i]-cnt;
			if(dif>=20){
				while(dif>=20){
					dif-=20;
					mem=(mem*buf)%beki;
				}
				mem=(mem*((int)Math.pow(2, dif)%beki))%beki;

			}else{
				mem*=((int)Math.pow(x, dif)%beki);
			}
			ans=(ans+mem)%beki;
			cnt+=(a[i]-cnt);
		}
		System.out.println(ans);
	}
}