import java.util.Scanner;
public class Main {

	public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);

		long L = sc.nextLong();
		long R = sc.nextLong();
		sc.close();
		long anser = 0;
		long min = 2 * (long) Math.pow(10, 9);
		//大きすぎる値は制約を越えるので０を出す
		if(R-L>=2018) System.out.println(0);
		else {
			for(long i = L ; i<=R;i++) {
				for(long j = i+1; j <= R; j++) {
					anser = (i*j)%2019;
					min = Math.min(anser, min);
				}
			}
		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