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 Go (1.14.1) (judge verdict: Wrong Answer)

package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
	"strings"
)

func main() {
	var scanner = bufio.NewScanner(os.Stdin)
	var p string
	if scanner.Scan() {
		p = scanner.Text()
	}
	slice := strings.Split(p, "")
	s := 0
	s2 := 1
	m := map[int]int{}
	m[0]++
	for i := len(slice) - 1; i >= 0; i-- {
		q, _ := strconv.Atoi(slice[i])
		s += s2 * q
		m[s%2019]++
		s2 *= 10
		s2 %= 2019
	}
	ans := 0
	for _, v := range m {
		ans += v * (v - 1) / 2
	}
	fmt.Println(ans)

}