using System;

using System.Linq;

using System.Text;

public class Program

{

    public static void Main()

    {

        var cipher = new QwertyCipher();

        var text = "The quick brown fox jumped over the lazy dog.";

        var scrambled = cipher.Transform(text, 2);

        Console.WriteLine(scrambled);

        Console.WriteLine(cipher.Transform(scrambled, 2, true));

    }

    public class QwertyCipher

    {

        readonly char[] topRow = new char[] { 'q', 'w', 'e', 'r', 't', 'y', 'u', 'i', 'o', 'p' };

        readonly char[] middleRow = new char[] { 'a', 's', 'd', 'f', 'g', 'h', 'j', 'k', 'l' };

        readonly char[] bottomRow = new char[] { 'z', 'x', 'c', 'v', 'b', 'n', 'm' };

​

        public string Transform(string text, int spaces, bool reverse = false)

        {

            var result = new StringBuilder();

            foreach(var letter in text)

            {

                var isUpper = char.IsUpper(letter);

                var c = char.ToLower(letter);

                var row = FindRow(c, reverse);

                if (row == null)

                {

                    result.Append(c);

                    continue;

                }

                if (isUpper)

                {

                    result.Append(char.ToUpper(ShiftOnRow(row, c, spaces)));

                }

                else

                {

                    result.Append(ShiftOnRow(row, c, spaces));

                }

            }

            return result.ToString();

        }

​

        char ShiftOnRow(char[] row, char letter, int spaces)

        {

            var index = Array.IndexOf(row, letter);

            return row[(index + spaces) % row.Length];

        }

​

        char[] ReverseArray(char[] array)

        {

            var reversed = (char[])array.Clone();

            Array.Reverse(reversed);

            return reversed;

        }

​

        char[] FindRow(char letter, bool reverse)

        {

            if (topRow.Any(l => l == letter))

            {

                if (reverse)

                {

                    return ReverseArray(topRow);

                }

​

                return topRow;

            }

​

            if (middleRow.Any(l => l == letter))

            {

                if (reverse)

                {

                    return ReverseArray(middleRow);

                }

​

                return middleRow;

            }

​

            if (bottomRow.Any(l => l == letter))

            {

                if(reverse)

                {

                    return ReverseArray(bottomRow);

                }

​

                return bottomRow;

            }

​

            return null;

        }

    }

}