import java.util.*;
public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int L = sc.nextInt();
		int R = sc.nextInt();
		if(R-L > 673) {
			System.out.println(0);
			return;
		}
		L %= 2019;
		R %= 2019;
		if(L >= R)
			R += 2019;
		int ans = 2018;
		for(int i = L; i < R; i++)
			for(int j = i+1; j <= R; j++)
				ans = Math.min(ans, i * j % 2019);
		System.out.println(ans);
	}

}

/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz