Square Numbers

using System;
using System.Collections.Generic;
using System.Linq;

class Program
{
    static void Main()
    {
        List<double> numbers = Console.ReadLine().Split(new[] { ' ' }, StringSplitOptions.RemoveEmptyEntries).Select(double.Parse).ToList();
        List<double> squareNumbers = new List<double>();
        for (int i = 0; i < numbers.Count; i++)
        {
            if ((numbers[i] == MathPow(MathSqrt(numbers[i])) && numbers[i]!=0))
            {
                squareNumbers.Add(numbers[i]);
            }
        }
        squareNumbers.Sort();
        squareNumbers.Reverse();
        Console.WriteLine(string.Join(" ", squareNumbers));
    }

    static double MathPow(double num)
    {
        double result;

        result = num*num;
        return result;
    }

    public static double MathSqrt(double num)
    {
        if (num == 0)
        {
            return 0;
        }
        double n = (num / 2) + 1;
        double n1 = (n + num / n) / 2;
        while (n1 < n)
        {
            n = n1;
            n1 = (n + (num / n)) / 2;
        } // end while
        return n;
    }
}