import java.util.*;


 class Main
 { 
	public static void main(String args[])
 	{ 

		Scanner sc =new Scanner(System.in);
		long l = sc.nextInt();
		long r = sc.nextInt();
		
		long res = Integer.MAX_VALUE;
		
		if(r - l >= 2019){
			System.out.println(0); 
			return;
		}
		
		for(long i = l; i <= r; i++){
			for(long j = i+1; j <= r; j++){
				res = Math.min(res, i*j%2019);
			}
		}
		
		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