using System;

public class Program

{

    public static void Main()

    {

        long N = 1000100001000;

        string n = Convert.ToString(N);

        int index = n.LastIndexOf("0", n.Length - 1);

        Console.WriteLine(index);

        for (int i = n.Length - 2; i >= 0; i--)

        {

            int counter = 1;

            counter++;

            int old = index;

            index = n.LastIndexOf("0", index - 1);

            if (old - index > 1)

            { Console.WriteLine("!!!!" + counter); }

            else { Console.WriteLine(index); }

        }

    }

}

​

//Write a program that calculates with how many zeroes the factorial of

//a given number ends. Examples:

//N = 10 -> N! = 3628800 -> 2

//N = 20 -> N! = 2432902008176640000 -> 4