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 JavaScript (node.js v5.12) (judge verdict: Wrong Answer)

function Main(input) {
  var tmp = input.split(' ')
  var L = tmp[0]
  var R = tmp[1]

  var result = 2019
  var temp = 0

  for (var i = 0; i < R - L; i++) {
    for (var j = 1; j < R - L - i + 2; j++) {
      var num1 = parseInt(L) + i
      var num2 = parseInt(L) + i + j
      temp = num1 * num2
      if (temp % 2019 < result) {
        result = temp % 2019
      }
    }
  }

  console.log('%d', result)
}

Main(require('fs').readFileSync('/dev/stdin', 'utf8'))