import java.io.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.HashSet;
import java.util.Scanner;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 */
public class Main {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        Scanner in = new Scanner(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        RemainderMinimization2019 solver = new RemainderMinimization2019();
        solver.solve(1, in, out);
        out.close();
    }

    static class RemainderMinimization2019 {
        public void solve(int testNumber, Scanner in, PrintWriter out) {
            HashSet<Long> set = new HashSet<>();
            long l = in.nextLong();
            long r = in.nextLong();

            if (r - l > 2019) {
                out.println(0);
                return;
            }
            long result = Long.MAX_VALUE;

            for (long i = l; i < r; i++) {
                for (long j = i + 1; j <= r; j++) {
                    result = Math.min(result, i * j % 2019);
                }
            }
            out.println(result);
        }

    }
}


/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