import java.io.*;

public class Main{
	public static final int YEAR = 2019;
	
	public static void main(String[] args) throws IOException{
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		String[] line = br.readLine().split(" ");
		int L = Integer.parseInt(line[0]);
		int R = Integer.parseInt(line[1]);
		
		if( R - L != R%YEAR - L%YEAR ){
			System.out.println(0);
		}else{
			L %= YEAR; R %= YEAR;
			int min = L*(L+1)%YEAR;
			for(int i=L; i<R; i++) for(int j=i+1; j<=R; j++)
				if( i*j%YEAR < min )
					min = i*j%YEAR;
			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