import java.util.Scanner;

public class Main {

    public static void main(String[] args) {
        
        Scanner sc = new Scanner(System.in);
        
        int l = Integer.parseInt(sc.next());
        int r = Integer.parseInt(sc.next());
        
        long min = 2019;
        long rem;
        for(long i = l; i <= r-1; i++){
            for(long j = i+1; j <= r; j++){
                rem = (i*j) % 2019;
                if(rem < min){
                    min = rem;
                    if(min == 0){
                        break;
                    }
                }
            }
            if(min == 0){
                break;
            }
        }
        
        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