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 + 1 >= 2019 || r % 2019 < l % 2019) {
		    System.out.println(0);
		    return;
		}
		int min = Integer.MAX_VALUE;
		for (int i = l; i < r; i++) {
		    for (int j = i + 1; j <= r; j++) {
		        min = Math.min(min, (i % 2019) * (j % 2019) % 2019);
		    }
		}
		System.out.println(min);
   }
}

/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