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 Kotlin (1.0.0) (judge verdict: Accepted)

import java.util.Scanner

var max=2020L
val mod=2019L
fun main(args:Array<String>){
    val sc=Scanner(System.`in`)
    var L=sc.nextLong()
    var R=sc.nextLong()

    for( i in (L+1)..Math.min(L+2019,R)){
        for(j in L..(i-1)){
            max=Math.min(max,i*j%mod)
        }
    }
    println(max)
}