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)

"use strict";
const main = input => {
  input = input[0].split(' ').map(val => parseInt(val, 10));
  const l = input[0], r = input[1];
  // console.log(l, r);
  let num = 0;
  if (r > 2019) {
    if (l < 2019) {
      num = 2019*2020;
    } else {
      num = l*(l+1);
    }
    num = num%2019;
  } else {
    num = l*(l+1);
  }
  console.log(num);
  
  
  
};
main(require("fs").readFileSync("/dev/stdin", "utf8").split('\n'));