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();
        long opt=2019;
        if(L==0||R-L>=2019) opt=0;
        else{
            for(long i=L;i<R;i++){
                for(long j=i+1;j<=R;j++){
                    long num = (i*j)%2019;
                    if(opt>num) opt=num;
                }
            }
        }
        System.out.println(opt);
    }
}

/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