import java.io.*;
import java.math.BigInteger;
import java.util.*;


public class  Main{
    public static void main(String[] args) throws Exception{
    	MScanner sc = new MScanner(System.in);
        //MScanner sc = new MScanner("reduce.in");
        PrintWriter pw=new PrintWriter(System.out);
        int l=sc.nextInt();int r=sc.nextInt();
        if(r-l+1>=2019) {
        	pw.println(0);
        }
        else {
        	int ans=1000000000;
        	for(int i=l;i<=r;i++) {
        		for(int j=i+1;j<=r;j++) {
        			ans=(int)Math.min(ans,(i*1l*j*1l)%2019);
        		}
        	}
        	pw.println(ans);
        }
        pw.flush();
    }
    
    
    static class MScanner {
		StringTokenizer st;
		BufferedReader br;
 
		public MScanner(InputStream system) {
			br = new BufferedReader(new InputStreamReader(system));
		}
 
		public MScanner(String file) throws Exception {
			br = new BufferedReader(new FileReader(file));
		}
 
		public String next() throws IOException {
			while (st == null || !st.hasMoreTokens())
				st = new StringTokenizer(br.readLine());
			return st.nextToken();
		}
 
		public String nextLine() throws IOException {
			return br.readLine();
		}
 
		public int nextInt() throws IOException {
			return Integer.parseInt(next());
		}
 
		public double nextDouble() throws IOException {
			return Double.parseDouble(next());
		}
 
		public char nextChar() throws IOException {
			return next().charAt(0);
		}
 
		public Long nextLong() throws IOException {
			return Long.parseLong(next());
		}
 
		public boolean ready() throws IOException {
			return br.ready();
		}
 
		public void waitForInput() throws InterruptedException {
			Thread.sleep(3000);
		}
	}
}
/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