import java.util.*;

public class Main {
    public static void main(String[] args) throws Exception {
        // Your code here!
        Scanner sc = new Scanner(System.in);
        int l = sc.nextInt();
        int r = sc.nextInt();
        
        if (r - l >= 2018) {
            System.out.println(0);
            return;
        }
        
        int min = 2000000000;
        for (int i = l; i < r; i++) {
            for (int j = l + 1; j <= r; j++) {
                long tmp = ((long)i * j) % 2019;
                int tmp2 = (int)tmp;
                tmp = 1;
                min = Math.min(min, (int)tmp*tmp2);
            }
        }
        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