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 C# (.NET Core 3.1.201) (judge verdict: Runtime Error)

using System;
using System.Linq;

public class Progaram
{
  public static void Main()
  {
    var s = Console.ReadLine();
    int count = 0;
    for(int i = 0; i < s.Length - 4; i++)
    {
      for(int j = 4; j <= s.Length - i; j++)
      {
        long remained = 0;
        for(int k = 0; k < j; k += 19)
        {
          var length = Math.Min(j - k, 19);
          for(int l = 0; l < length; l++)
          {
            remained *= 10;
          }
          var text = s.Substring(i + k, length);
          remained  = (remained + long.Parse(text)) % 2019;                     
        }
        if(remained == 0)
        {
          count++;
        }
      }
    }
    Console.WriteLine(count);
  }
}