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 Scala (2.11.7) (judge verdict: Wrong Answer)

object Main{

def main(args: Array[String]): Unit = {
  val arr1 = io.StdIn.readLine().split(' ')
  val L = arr1(0).toInt
  val R = arr1(1).toInt
  
  val given = 2019 // = 1 x 3 x 673
  val pf1 = 3
  val pf2 = 673
  val res = R - L
  
  if(res >= pf2 - 1){
    println("0")
  }else{
    var min = 2018
    (L until R).foreach{
      i =>
      (i + 1 to R).foreach{
        j => 
      val k = (i % 2019) * (j % 2019)
      if(min > k) min = k
      }
    }
    println(min)
  }
}
}