using System;

using System.Collections.Generic;

using System.Linq;

​

public class Program

{

    private static Dictionary<int, int> _holeMap = new Dictionary<int, int>

    {

        { 0, 1 },

        { 1, 0 },

        { 2, 0 },

        { 3, 0 },

        { 4, 1 },

        { 5, 0 },

        { 6, 1 },

        { 7, 0 },

        { 8, 2 },

        { 9, 1 }                

    };

​

    public static void Main()

    {

        int number = 8857980;

        int check = CountHoles(number);

        Console.WriteLine(check);   

    }

​

    public static int CountHoles(int num){

        var digits = num

            .ToString()

            .Select(c => int.Parse(c.ToString()));

​

        return digits.Sum(d => _holeMap[d]);

    }

}