import java.util.Scanner;

class Main{
  public static void main(String[] args){
    Scanner sc = new Scanner(System.in);
    long l = sc.nextLong();
    long r = sc.nextLong();
    
    r   = Math.min(r, l+2019);
    long min = 2018;
    for(long i = l; i <= r; i++)
      for(long j = i+1; j <= r; j++)
          min = Math.min(min, i*j%2019);
    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