Bit Builder 02.

using System;

namespace _5.BitBuilder
{
    class BitBuilder
    {
        static void Main()
        {

            bool check = true;
            long newNumber = 0;
            string input = Console.ReadLine();

            if (input == "quit")
            {
                Console.WriteLine(newNumber);
                check = false;
                System.Environment.Exit(-1);
            }
            else
            {
                newNumber = long.Parse(input);
            }

            do
            {
                input = Console.ReadLine();

                if (input == "quit")
                {
                    Console.WriteLine(newNumber);
                    check = false;
                    System.Environment.Exit(-1);
                }
                else
                {
                    int position = int.Parse(input);
                    string manipulation = Console.ReadLine();

                    switch (manipulation)
                    {
                        case "flip":
                            newNumber = flipBit(newNumber, position);
                            break;
                        case "insert":
                            newNumber = insertBit(newNumber, position);
                            break;
                        case "remove":
                            newNumber = removeBit(newNumber, position);
                            break;
                    }
                }
            }
            while (check);
        }



        private static long flipBit(long number, int position)
        {
            long tempMask = (long)1 << position;
            long result = number ^ tempMask;
            return result;
        }

        private static long removeBit(long number, int position) // 123, 3
        {
                                                           // 0111 1011
            long mask = bitMaskFromN(position - 1);        // 0000 0111
            long tempNumber = mask & number;               // 0000 0011

            number = number >> position + 1;               // 0000 0111
            number = number << position;                   // 0011 1000
            number = number | tempNumber;                  // 0011 1011
            return number;
        }

        private static long insertBit(long number, int position) // 123, 3
        {
                                                           //     0111 1011
            long mask = bitMaskFromN(position - 1);        //     0000 0111
            long invertMask = invertBitMasks(mask);        // (1) 1111 1000
            long tempMask = (long)1 << position;           //     0000 1000
            long tempNumber = mask & number;               //     0000 0011

            number = invertMask & number;                  //     0111 1000
            number = number << 1;                          //     1111 0000
            number = number | tempMask;                    //     1111 1000
            number = number | tempNumber;                  //     1111 1011
            return number;
        }

        public static long bitMaskFromN(int position)
        {
            if (position < 0)
            {
                return 0;
            }
            string maskBits = "";
            for (int i = 0; i <= position; i++)
            {
                maskBits += '1';
            }
            long maskNumber = Convert.ToInt64(maskBits, 2);
            return maskNumber;
        }

        private static long invertBitMasks(long mask)
        {
            long result = mask ^ ((long)-1);
            return result;
        }
    }
}