import java.util.*;

import static java.lang.Math.round;

public class Main{
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        int l = sc.nextInt();
        int r = sc.nextInt();
        int modl =   l% 2019;
        int modr = r%2019;
        long ans =2018;

        if(modr<= r-l){
            System.out.println(0);
        }else{
            for(int p=modl; p < modr; p++){
                for(int q=p+1; q <= modr; q++){
                    ans = Math.min(ans, (p*q)%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