import java.util.*;

class Main{
    final static long mod = 1000000007;
    //
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        int l = sc.nextInt();
        int r = sc.nextInt();
        int min = 2018;
        if(r / 2019 - l / 2019 >= 1){
            System.out.println(0);
            return;
        }
        l %= 2019;
        r %= 2019;
        for(int i = l; i <= r; i++){
            for(int j = i + 1; j <= r; j++){
                min = Math.min(min, i * j % 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