import java.util.*;
import java.lang.*;

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;
        
        if (r - l <= 3000) {
            for (long i = l; i <= r - 1; i++) {
                for (long j = i + 1; j <= r; j++) {
                    long mod = i * j % 2019;
                    if (mod < min) {
                        //System.out.println(i + ", " + j);
                        min = mod;
                    }
                }
            }
        } else {
            min = 0;
        }
        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