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();
		int min = (L%2019)*(R%2019)%2019;
		if (R-L > 2019){
		    System.out.println(0);
		    return;
		}
		for(int i=L;i<R;i++){
		    for(int j=i+1;j<=R;j++){
		        if((i%2019)*(j%2019)%2019 < min){
		            min = (i%2019)*(j%2019)%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