import java.util.Scanner;

public class Main {
	public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);
		long l = sc.nextInt();
		long r = sc.nextInt();
		long min = 2018;
		for (long i = l; i < r; i++) {

			for (long j = i + 1; j <= r; j++) {
				if (min == 0)
					break;
				if (i * j % 2019 < min)
					min = i * j % 2019;
				if (min == 0)
					break;
			}
		}

		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