import java.util.*;
public class Main{
  public static void main(String[] args){
    Scanner sc = new Scanner(System.in);
    long L = sc.nextLong(); 
    long R = sc.nextLong(); 

    long min = 2019;
    if(R-L>=2018){
      System.out.println(0);
      return;
    }
    for(long i=L; i<R;i++){
      // System.out.println(i);
      for(long j=i+1; j<=R;j++){
        // System.out.println(i+"aaa");
        min = Math.min((i*j)%2019, 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