import java.util.Scanner;

public class Main {
	final static long mod = 2019;
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		long L = sc.nextLong();
		long R = sc.nextLong();
		sc.close();
		// System.out.println("L/2019=" + L / mod + " R/2019=" + R / mod);
		if(L / mod != R / mod) { System.out.println(0); return; }
		long min = Long.MAX_VALUE;
		for(long i = L; i <= R - 1; i++) {
			for(long j = i + 1; j <= R; j++) {
				long r = (i * j) % mod;
				// System.out.println(i + "*" + j + "%2019=" + r);
				// if(r == 0) { System.out.println(0); return; }
				min = Math.min(min, r);
			}
		}
		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