binary search tree reversal, C#

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//Rextester.Program.Main is the entry point for your code. Don't change it.
//Compiler version 4.0.30319.17929 for Microsoft (R) .NET Framework 4.5

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text.RegularExpressions;

namespace CodingAlgorithms
{
    public static class ReverseWords
    {
        //Reverse words in a string
        public static string Reverse(string s)
        {
            string result = "";
            Stack temp = new Stack();
            s = s.Trim();
 
            //Remove extra white space between characters
            while (s.Contains("  "))
                s = s.Replace("  ", " ");
 
            //Store each word on the Stack
            foreach (string x in s.Split(' '))
                temp.Push(x);
 
            //Add each word to the result string in reverse order since a stack is a FIFO data structure
            while (temp.Count != 0)
                result += temp.Pop() + " ";
 
            return result.Trim();
        }
    }
}

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