Exam 7. Bit Shooter

using System;
using System.Globalization;
using System.Threading;

public class BitShooter
{
    public static void Main()
    {
        Thread.CurrentThread.CurrentCulture = CultureInfo.InvariantCulture;
        checked
        {
            ulong number = ulong.Parse(Console.ReadLine());

            int leftBits = 0;
            int rightBits = 0;
            if (number > 0)
            {
                for (int i = 0; i < 3; i++)
                {
                    string[] inputStr = Console.ReadLine().Split(new char[] { ' ', ',', ';' }, StringSplitOptions.RemoveEmptyEntries);
                    int center = int.Parse(inputStr[0]);
                    int size = int.Parse(inputStr[1]);
                    int damageMinBitPosition = center - (size / 2);
                    if (damageMinBitPosition < 0)
                    {
                        damageMinBitPosition = 0;
                    }

                    int damageMaxBitPosition = center + (size / 2);
                    if (damageMaxBitPosition > 63)
                    {
                        damageMaxBitPosition = 63;
                    }

                    int countBitsToChange = (damageMaxBitPosition - damageMinBitPosition) + 1;
                    ulong bitMask = ((ulong)1 << countBitsToChange) - 1;
                    bitMask <<= damageMinBitPosition;
                    number &= ~bitMask;
                }

                for (int bits = 0; bits < 64; bits++)
                {
                    int bitValue = (int)(number & 1);
                    if (bits >= 32 && bitValue > 0)
                    {
                        leftBits++;
                    }
                    else if (bits < 32 && bitValue > 0)
                    {
                        rightBits++;
                    }

                    if (number == 0)
                    {
                        break;
                    }

                    number >>= 1;
                }
            }

            Console.WriteLine("left: {0}\nright: {1}", leftBits, rightBits);
        }
    }
}