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 C++14 (GCC 5.4.1) (judge verdict: Runtime Error)

#include <bits/stdc++.h>
using namespace std;



int main() {
  int L,R;
  cin>>L>>R;
  vector<int>amari(R-L+1);
  int init = L%2019;
  int ret;
  if((R-L+1)>=2019||L==0){
    ret=0;
  }else{
    for(int i=0;i<(R-L+1);i++){
    amari.at(i)=(L+i)%2019;
  }
    sort(amari.begin(),amari.end());
    ret=  amari.at(0)*amari.at(1);
  }
  cout<<ret<<endl;
}