WA on test #2 ?!??
C# code:

using System;
using System.Text;

class Program
{
    static void Main()
    {
        System.Threading.Thread.CurrentThread.CurrentCulture = System.Globalization.CultureInfo.InvariantCulture;
        string[] nums = Console.In.ReadToEnd().Split(' ');
        for (int i = nums.Length - 1; i >= 0; --i)
            try { Console.WriteLine("{0:F4}", Math.Sqrt(ulong.Parse(nums[i]))); }
            catch (Exception) { /* Do nothing if nums[i] is not a number */ }
    }
}

Edited by author 08.01.2007 13:21

oops. Stupid mistake - Split(' ') is not enought ...
I got AC !

using System;
using System.Threading;
using System.Globalization;
using System.Text.RegularExpressions;

class Program
{
  static void Main()
  {
    Thread.CurrentThread.CurrentCulture = CultureInfo.InvariantCulture;
    string[] nums = Regex.Split(Console.In.ReadToEnd().Trim(), @"\s+");
    for (int i = nums.Length - 1; i >= 0; i--)
      Console.WriteLine("{0:F4}", Math.Sqrt(ulong.Parse(nums[i])));
  }
}

above is ACCEPTED, but why Wrong answer in Test#1 if miss:
Thread.CurrentThread.CurrentCulture = CultureInfo.InvariantCulture;

using System;
using System.Collections;

public class Phone
{
   public static void Main(string[] args)
      {
         System.Threading.Thread.CurrentThread.CurrentCulture = System.Globalization.CultureInfo.InvariantCulture;
         string input;
         ArrayList al = new ArrayList();

         while((input=Console.ReadLine())!=null)
            {
               string[] d=input.Split(new string[]{" ","\t"},StringSplitOptions.RemoveEmptyEntries);
               foreach(string t in d)
                  {
                     if(t!="")
                        {
                           al.Add(double.Parse(t));
                        }

                  }
            }
         for(int i=al.Count-1;i>=0;i--)
            {
               Console.WriteLine("{0:f4}",Math.Sqrt((double)al[i]));
            }
      }



}

Same here, if I miss the thread line, it gives WA #1, otherwise is OK. Why? What does it do?