Problem:
Score : 400 points

Problem Statement

Given is a string S consisting of digits from 1 through 9.

Find the number of pairs of integers (i,j) (1 ≤ i ≤ j ≤ |S|) that satisfy the following condition:

Condition: In base ten, the i-th through j-th characters of S form an integer that is a multiple of 2019.

Constraints

1 ≤ |S| ≤ 200000

S is a string consisting of digits from 1 through 9.

Input

Input is given from Standard Input in the following format:

S

Output

Print the number of pairs of integers (i,j) (1 ≤ i ≤ j ≤ |S|) that satisfy the condition.

Sample Input 1

1817181712114

Sample Output 1

3

Three pairs - (1,5), (5,9), and (9,13) - satisfy the condition.

Sample Input 2

14282668646

Sample Output 2

2

Sample Input 3

2119

Sample Output 3

0

No pairs satisfy the condition.

Solution in Scala (2.13.1) (judge verdict: Time Limit Exceeded)

import java.util.Scanner

object Main extends App {
  val sc = new Scanner(System.in)
  val S = sc.nextLine()
  val a = Array.tabulate(S.length)(x => BigInt(S.takeRight(x + 1)).mod(BigInt(2019))) :+ BigInt(0)
  val b = a.groupBy(_.toInt).view.mapValues(_.length).values.map(x => x * (x - 1) / 2).sum

  println(b)
}