using System;

using System.Collections.Generic;

using System.Linq;

using System.Text.RegularExpressions;

using System.Text;

​

public class Program

{

    public static void Main()

    {

        var chars = "0101000000000000000000000000000B0000000000000000000000000010100F01111B00000000000000000000000000101000F0100110000000000B";

        /*

        Above represents a stream of binary encoded numbers. Each number is terminated by B or F

        If terminated by B the bit for that number were backwards

        If terminated by F the bits for that number were forward

        Print out the numbers on their own line in the order they are in the stream without mutation. 

        For clarity, buffer is mutating frequently below.

        */

​

        Regex r = new Regex("(?<bin>[01]*)(?<dir>[FB])", RegexOptions.IgnoreCase);

        foreach( Match item in r.Matches(chars)){

            string dir = Convert.ToString(item.Groups["dir"]);

            string binary = Convert.ToString(item.Groups["bin"]);

            if( dir == "B" ){

                Console.WriteLine(Convert.ToInt32(ReverseSB(binary),2));

            }

            else{

                Console.WriteLine(Convert.ToInt32(binary,2));

            }

        }

    }

    public static string ReverseSB(string text)

    {

        StringBuilder builder = new StringBuilder(text.Length);

        for (int i = text.Length - 1; i >= 0; i--)

        {

            builder.Append(text[i]);

        }

        return builder.ToString();

    }   

}