Reverse Words In A Sentence Keep Punctuation

using System;
using System.Collections.Generic;

class ReverseWordsInASentencesKeepPunctuation
{
  //Write a program that reverses the words in given sentence.
  //Example: "C# is not C++, not PHP and not Delphi!" -> "Delphi not and PHP, not C++ not is C#!".


  static void Main()
  {
    string text = "C# is not C++, not PHP and not Delphi!"; //Text to reverse

    List<string> reversedSentence = new List<string>(); //List that stores the words of the sentence
    List<string> punctuation = new List<string>();//List that stores the punctuation of the sentence

    string word = ""; //temporary string for each word construction
    string separator = "";//temporary string for each punctuation construction (e.g. if you have comma and interval theay should be stored together as ", ")

    foreach (char item in text) //Iterate through the text
    {
      if (char.IsSymbol(item) || char.IsLetterOrDigit(item) || item == '#') //If you have a letter,digit or symbol
      {
        if (separator != "") //if the separator has value
        {
          punctuation.Add(separator);//add it to the punctuation list
        }

        word += item; //construct a word
        separator = ""; //Empty the separator constructor
      }
      else if (char.IsSeparator(item) || char.IsPunctuation(item) || char.IsWhiteSpace(item))//If you have a separator or punctuation
      {
        if (word != "")//if our word has value
        {
          reversedSentence.Add(word);//Add it to the list of words in the sentence that will be reversed
        }

        separator += item;//construct a separator
        word = "";//Empty the word constructor
      }
    }

    if (separator !="")//If we have a separator value left
    {
      punctuation.Add(separator);//add it to the punctuation list
    }
    if (word != "")//If we have a word value left
    {
      reversedSentence.Add(word);//Add it to the list of words
    }

    //Print the output
    int printLength = Math.Max(reversedSentence.Count, punctuation.Count); //Get the list with more elements
    for (int k = 0, i = reversedSentence.Count - 1, j = 0; k < printLength; k++) //Cycle to the length of the longer list (k)
    {
      if (i >= 0)//Check for end of the words list
      {
        Console.Write(reversedSentence[i]);
        i--;
      }

      if (j < punctuation.Count)//Check for end of the punctuation list
      {
        Console.Write(punctuation[j]);
        j++;
      }
    }
    Console.WriteLine();
  }
}