import java.util.Scanner;

/**
 * Main
 */
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();
        
        int min = 2019;

        if(R-L > 2018){
            min = 0;
        }else{
         for(long i = L; i <= R-1; i++){
             for(long j= i+1; j <= R; j++){
                 long tmp = i*j%2019;
                 min = (int) Math.min(tmp, 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