import java.util.Scanner;

public class Main {

  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    long l = sc.nextLong();
    long r = sc.nextLong();

    if (r > l + 2018) {
      System.out.println(0);
      System.exit(0);
    }

    long res = 2019;

    for (long i = l; i <= r; ++i) {
      for (long j = l; j <= r; ++j) {
        if (i == j)
          continue;
        res = ((i * j) % 2019 < res) ? (i * j) % 2019 : res;
      }
    }

    System.out.println(res);
  }
}
/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