Palindromes

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApplication7
{
    class Program
    {

        static void Main(string[] args)
        {
            string input = Console.ReadLine();
            Console.WriteLine(ExtractPalindromes(input));
        }
       static string ExtractPalindromes(string input)
        {
            string[] arrayInput = input.Split(new string[] { "?", " ", "!", ",", "." }, StringSplitOptions.RemoveEmptyEntries);
            List<string> palindromes = new List<string>();
            foreach (var word in arrayInput)
            {
                string reversedWord = ReverseString(word);
                if (word == reversedWord)
                {
                    palindromes.Add(word);
                }
            }
            palindromes.Sort();
            string output = string.Join(", ", palindromes);
            return output;

        }
       static string ReverseString(string someString)
       {
           StringBuilder reverse = new StringBuilder();
           for (int i = someString.Length - 1; i >= 0; i--)
           {
               reverse.Append(someString[i]);
           }
           return reverse.ToString();
       }


    }
}