import java.util.*;

public class Main{
    public static void main(String args[]){
        Scanner sc = new Scanner(System.in);

        int L = sc.nextInt();
        int R = sc.nextInt();

        int min = 2019;
        if( (R-L) >= 2019)
            min = 0;
        else  {
            for(int i = 0; i <= (R-L+-1); i++){
                for(int j = i+1; j <= (R-L); j++){
                    int mod_i = (L+i) % 2019;
                    int mod_j = (L+j) % 2019;
                    int mod_ij = (mod_i * mod_j) % 2019;
                    if(mod_ij < min)
                        min = mod_ij;
                }
            }
        }
        System.out.println(min);
        sc.close();
    }
}
/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