30.08 Exam - Problem 5

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace waveBitsv2
{
    class Program
    {
        static void Main(string[] args)
        {
            ulong number = ulong.Parse(Console.ReadLine());
            int count = 0;
            int longestCount = 0;
            int bestPosition = 0;
            int currentPosition = 0;
            bool seqStarted = false;

            int lastDigit = -1;
            int currentDigit;

            for (int i = 0; i < 64; i++)
            {
                currentDigit = CheckBit(number, i);

                if ((currentDigit == 1 && currentDigit != lastDigit) && (seqStarted == false))
                {
                    count++;
                    seqStarted = true;
                    currentPosition = i;
                }

                else if (seqStarted == true && currentDigit != lastDigit)
                {
                    count++;
                }

                else
                {
                    if (longestCount < count)
                    {
                        longestCount = count;
                        bestPosition = currentPosition;
                    }
                    count = 0;
                    seqStarted = false;

                }

                lastDigit = currentDigit;
            }




            if (longestCount == 1)
            {
                Console.WriteLine("No waves found!");
            }

            else
            {
                number = RemoveBitV2(number, bestPosition, longestCount);
                Console.WriteLine(number);
            }


            //Console.WriteLine(longestCount);
            //Console.WriteLine(bestPosition);
        }

        public static int CheckBit(ulong number, int position)
        {
            if ((number & (ulong)1 << position) == 0)
            {
                return 0;
            }
            else
            {
                return 1;
            }
        }

        public static ulong RemoveBitV2(ulong number, int position, int count)
        {
            ulong mask = 0;

            for (int i = 0; i < position; i++)
            {
                mask <<= 1;
                mask |= 1;
            }

            ulong rightBits = number & mask;

            number >>= position + count;
            number <<= position;
            return number |= rightBits;

        }
    }
}