calculatesZero

using System;
//Write a program that calculates for given N how many trailing zeros present at the end of the number N!. Examples:
//N = 10 --> N! = 3628800 --> 2
//N = 20 ->> N! = 2432902008176640000  --> 4
class CalculatesZero
{
    static void Main()
    {
        int fact = int.Parse(Console.ReadLine());
        int zero = 0;
        double number = 0; // save current value of number multiplied by five

        for (int i = 1; i <= fact; i++)
        {
            number = i;
            while(number % 5 == 0)
            {
                zero++;
                number /= 5;
                if (number % 5 != 0) // if the number is divisible by five, repead the operation, else
                {                    // break , and get another i !
                    break;
                }
            }
        }
        Console.WriteLine(zero);
    }
}