Palindroms

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

namespace Palindroms
{
    class Program
    {
        static void Main(string[] args)
        {
            List<string> input = Console.ReadLine().Split(new[] {' ', ',', '.', '?', '!' }, StringSplitOptions.RemoveEmptyEntries).ToList();
            //
            List<string> palindroms = new List<string>();
            //
            foreach (var word in input)
            {
                var currentWord = word;
                var reversedWord = "";
                for (int i = word.Length-1; i >= 0 ; i--)
                {
                    reversedWord += word[i];
                }
                if (currentWord == reversedWord)
                {
                    palindroms.Add(reversedWord);
                }
                reversedWord = "";
            }
            Console.WriteLine(string.Join(", ", palindroms.OrderBy(x => x).Distinct()));
        }
    }
}