[Programming Basics Exam - 17 January 2016] Problem 05 - Eme

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

class EmergencyRepairs
{
    static void Main()
    {
        ulong wall = ulong.Parse(Console.ReadLine());
        int emergencyKits = int.Parse(Console.ReadLine());
        int numberOfAttacks = int.Parse(Console.ReadLine());

        //determine damages after the attacks
        for (int i = 0; i < numberOfAttacks; i++)
        {
            int attack = int.Parse(Console.ReadLine());
            if (((wall >> attack) & 1) == 1)
            {
                ulong mask = ~((ulong)1 << attack);
                wall = wall & mask;
            }
        }

        //find big holes
        int bitCounter = 0;
        while (emergencyKits > 0)
        {
            if (((wall >> bitCounter) & 1) == 0 &&
                (((wall >> (bitCounter + 1)) & 1) == 0))
            {
                ulong mask = (ulong)1 << bitCounter;
                wall = wall | mask;
                emergencyKits--;

                if (emergencyKits > 0)
                {
                    bitCounter++;
                    mask = (ulong)1 << bitCounter;
                    wall = wall | mask;
                    emergencyKits--;
                }
            }
            bitCounter++;
        }

        //find small holes
        bitCounter = 0;
        while (emergencyKits > 0)
        {
            if (((wall >> bitCounter) & 1) == 0)
            {
                ulong mask = (ulong)1 << bitCounter;
                wall = wall | mask;
                emergencyKits--;
            }
            bitCounter++;
        }

        Console.WriteLine(wall);

    }
}