const int SIMULATION_DURATION = 60 * 12; // one shift

        public void processPatients()
        {
            IQueue <Patient> waitingRoom = null;
            bool             usePriority = false;//orig false

            // create an array or list of ERTables
            ERTable[] tables = new ERTable[NUM_TABLES];

            // TODO -- populate the array with tables
            for (int i = 0; i < NUM_TABLES; i++)/////////////colin
            {
                tables[i] = new ERTable();
            }

            // this for loop will run twice, once with a SimpleQueue and once with the PriorityQueue
            for (int i = 0; i < 2; i++)
            {
                Console.WriteLine("\nUsing Priority Queue: {0}", usePriority);
                int  totalExpired     = 0;
                int  totalPatients    = 0;
                int  maxWait          = 0;
                int  tmpMaxWait       = 0;
                int  totalWait        = 0;
                int  totalStay        = 0;
                int  maxWaitingInLine = 0;
                int  tmpWaitingInLine = 0;
                bool stillWorking     = false;


                // TODO -- create triage unit
                TriageUnit      triageUnit = new TriageUnit();
                Queue <Patient> frontDoor  = triageUnit.getNewPatients();

                // TODO set the waitingQueue to one or the other type Queue, depending on the value of usePriority
                // you will need to instantiate the appropriate Queue in the if/else statement.
                if (usePriority == true)
                {
                    waitingRoom = new PriorityQueue <Patient>();
                    while (frontDoor.Count > 0)
                    {
                        Patient p = frontDoor.Dequeue();
                        waitingRoom.Add(p.LastPossibleMoment, p);
                    }
                }
                else if (usePriority == false)
                {
                    waitingRoom = new SimpleQueue <Patient>();
                    while (frontDoor.Count > 0)
                    {
                        Patient p = frontDoor.Dequeue();
                        waitingRoom.Add(p.LastPossibleMoment, p);
                    }
                }
                // Reset Hospital clock
                Hospital.CurrentTime = 0;

                while (Hospital.CurrentTime < SIMULATION_DURATION || waitingRoom.Count > 0 || stillWorking)
                {
                    // TODO empty tables that are free
                    // look for table where ETC <= currentTime
                    // do not look for expired patients; if they made it to an ER table, they lived
                    for (int j = 0; j < NUM_TABLES; j++)
                    {
                        if (tables[j].ETC <= Hospital.CurrentTime)
                        {
                            tables[j].Clear();
                        }
                    }
                    // NOTE: do the following *ONLY* if currentTime < simulation duration, otherwise you'll never finish
                    // TODO: get list of new patients from triage unit
                    if (Hospital.CurrentTime < SIMULATION_DURATION)
                    {
                        // for each patient in the triage queue
                        // set IntakeTime for each patient to 'currentTime'
                        // place new patients into waiting room
                        // when placing in waiting room, priority is the patient's last possible moment
                        frontDoor = triageUnit.getNewPatients();
                        foreach (Patient p in frontDoor)
                        {
                            p.IntakeTime = Hospital.CurrentTime;
                        }
                        while (frontDoor.Count > 0)
                        {
                            Patient p = frontDoor.Dequeue();
                            waitingRoom.Add(p.LastPossibleMoment, p);
                        }
                    }
                    // TODO: check for maximum number in waiting room
                    if (waitingRoom.Count > 0)
                    {
                        tmpWaitingInLine = waitingRoom.Count;
                        if (tmpWaitingInLine > maxWaitingInLine)
                        {
                            maxWaitingInLine = tmpWaitingInLine;
                        }
                    }
                    // TODO: for every EMPTY tables, be careful here
                    // remove next patient from waiting room
                    // check for expired patients (count them)
                    // (if the patient has expired, you'll need to get another one)
                    // placing living patients on empty ER table
                    // update any accumulators, maximums, etc.
                    for (int d = 0; d < NUM_TABLES; d++)
                    {
                        if (tables[d].IsFree && waitingRoom.Count > 0)
                        {
                            Patient p = waitingRoom.Remove();
                            //currenttime > intaketime + timetolive
                            if (Hospital.CurrentTime > p.IntakeTime + p.TimeToLive)
                            {
                                //died
                                totalExpired++;
                                p = null;
                            }
                            else if (Hospital.CurrentTime < p.IntakeTime + p.TimeToLive)
                            {
                                tmpMaxWait = Hospital.CurrentTime - p.IntakeTime;
                                if (tmpMaxWait > maxWait)
                                {
                                    maxWait = tmpMaxWait;
                                }
                                totalWait += Hospital.CurrentTime - p.IntakeTime;
                                //totalStay =
                                p.TimeEnteringER = Hospital.CurrentTime;
                                totalStay       += p.TimeEnteringER + p.TimeForProcedure - p.IntakeTime;
                                tables[d].AddPatient(p);
                                totalPatients++;
                            }
                        }
                    }

                    stillWorking = false;
                    // TODO: Make certain ALL of the tables are free
                    // if any table is not free, set stillWorking to true
                    for (int d = 0; d < NUM_TABLES; d++)
                    {
                        if (!tables[d].IsFree)
                        {
                            stillWorking = true;
                        }
                    }

                    // set add 10 minutes to hospital time
                    Hospital.CurrentTime += 10;
                }

                // print parameters (num tables, duration, using priority queue)
                // print time, total patients, max waiting, average waiting, expired patients
                Console.WriteLine("Total Elapsed Time: {0,7}", Hospital.CurrentTime);
                Console.WriteLine("Total patients:     {0,7}", totalPatients);
                Console.WriteLine("Total Expired:      {0,7}", totalExpired);
                Console.WriteLine("Longest Wait:       {0,7}", maxWait);
                Console.WriteLine("Average Wait:       {0,7:N2}", (double)totalWait / totalPatients);
                Console.WriteLine("Average Stay:       {0,7:N2}", (double)totalStay / totalPatients);
                Console.WriteLine("Maximum waiting:    {0,7:N2}", maxWaitingInLine);

                usePriority = true;
            } // end for
        }     // end processPatients