Problem:
Score : 300 points

Problem Statement

You are given two non-negative integers L and R.
We will choose two integers i and j such that L \leq i < j \leq R.
Find the minimum possible value of (i \times j) \mbox{ mod } 2019.

Constraints

All values in input are integers.

0 \leq L < R \leq 2 \times 10^9

Input

Input is given from Standard Input in the following format:

L R

Output

Print the minimum possible value of (i \times j) \mbox{ mod } 2019 when i and j are chosen under the given condition.

Sample Input 1

2020 2040

Sample Output 1

2

When (i, j) = (2020, 2021), (i \times j) \mbox{ mod } 2019 = 2.

Sample Input 2

4 5

Sample Output 2

20

We have only one choice: (i, j) = (4, 5).

Solution in Java8 (OpenJDK 1.8.0) (judge verdict: Wrong Answer)

import java.util.*;
public class Main {
	public static void main(String args[] ){
		Scanner sc =new Scanner(System.in);
	long n = sc.nextLong();
	long m =sc.nextLong();
	long min =Integer.MAX_VALUE;
	
	
	if(m<2019) {
		long data =(n*(n+1))%2019;
		min =data;
	}else{
		for(long i=n;i<m;i++) {
			for(long j=i+1;j<m;j++) {
				long data =(i*j)%2019;
				if(min > data) {
					//System.out.println(i+" "+j);
					min =data;
				}
				if(min==0) break;
				
			}
			if(min==0) break;
		}
		}
	
	
	System.out.println(min);
	
	
	}
}