
import java.util.*;

class Main{
    public static void main(String[] args) {
        Scanner stdIn = new Scanner(System.in);
        int L = stdIn.nextInt(); int R = stdIn.nextInt();
        int answer = 2018;
        if( R - L + 1 >= 673) answer = 0;
        else{
            for(int i = L; i <= R -1; i++){
                for(int j = i + 1; j <= R; j++){
                    if(answer > (i % 2019) * (j % 2019) % 2019){
                        answer = (i % 2019) * (j % 2019) % 2019;
                    }
                }
            }
        }
        System.out.println(answer);
    }
}
/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