import java.util.*;
class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        long l = sc.nextLong();
        long r = sc.nextLong();
        long min = Long.MAX_VALUE;
        int cnt = 0;
//        if(r-l>=2018) {
//            System.out.println(0);
//            return;
//        }
        for(long i = l; i<Math.min(r,l+2018); i++) {
            cnt=0;
            for(long j = i+1; j<=r; j++) {
                cnt++;
                if(cnt>=2019) break;
                min = Math.min((i*j)%2019, min);
            }
        }
        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