1024! 末尾有多少个0？

namespace MyNameSpace

{

    class MyClass

    {

        static void Main()

        {

            System.Console.WriteLine(new MyClass().CountZero(1024));

            System.Console.ReadKey();

        }

 

        public int CountZero(int num)

        {

            int result = 0;

 

            while (num > 5)

            {

                num = (num - (num % 5)) / 5;

                result += num;

            }

 

            return result;

        }

    }

}