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 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include<stdio.h>
#include<stdlib.h>
int main()
{
	int L, R, i, min_temp ;
	int min= 2019;

	scanf("%d", &L);
	scanf("%d", &R);

	if(R-L >= 2019){
		min = 0;
		printf("%d", min);
		return 0;
	}

	for(i=L; i<R; i+=2){
		min_temp = (i*(i+1))%2019;
		if(min_temp < min){
			min = min_temp;
		}
	}
	
	printf("%d", min%2019);		

	return 0;
}