import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner sc=new Scanner(System.in);
		int l=sc.nextInt(),r=sc.nextInt();
		sc.close();
		if(r-l>=2018) System.out.println(0);
		else {
			long min=2018;
			for(int i=l;i<r;i++) {
				for(int j=i+1;j<=r;j++) {
					long temp =(long)i*j;
					long mod = temp%2019;
					if(mod<min) min=mod;
				}
			}
			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