using System;

using System.Linq;

using System.Collections.Generic;

public class Program

{

    const string sentence = "Hello, how are you? Have you been to New Zeland?";

    public static void Main()

    {

        /**

         * Reverse each word in the below string, whilst preserving the position of punctuation.

         **/

        Console.WriteLine("olleH, woh era uoy? evaH uoy neeb ot weN dnaleZ?" == Reverse(sentence));

    }

    private static string Reverse(string s) {       

        string reversed = "";

        int i = 0;

        var parts = GetParts();

        parts.ForEach(_ => reversed += ReversePart(_, ref i));

        return reversed;

    }

    private static List<string> GetParts(){

        var punctList = sentence.Where(_ => char.IsPunctuation(_) || char.IsWhiteSpace(_)).ToArray();

        return new List<string> (sentence.Split(punctList));

    }

    private static string ReversePart(string part, ref int i) {

        i += part.Length;

        var punctuation = (i < sentence.Length)? sentence[i].ToString():"";

        i ++;

        var charArray = part.ToCharArray();

        Array.Reverse(charArray);

        return string.Concat(new string(charArray), punctuation);

    }

}