private void LeaveEvent(Customer customer)
        {
            // generates a random interval for how long the person takes, with a minimum of 1 minute
            // and 30 seconds
            TimeSpan waiting = new TimeSpan(0, 0, (int)(120 + Negex(AvgCheckoutTime.TotalSeconds - 120)));

            // Creates departure event based on the time interval plus the time we are currently
            // at in the Priority Queue
            Event e = new Event(EVENTTYPE.LEAVE, ((EventPriorityQueue.Peek().Time + waiting)));

            //Associates departure event with registrant
            e.CurrCustomer = customer;
            customer.Leave = e;

            // Adds departure event to the queue
            EventPriorityQueue.Enqueue(e);

            // Update wait times for statistic counters
            TotalTime += waiting;

            if (waiting > LongestTime)
            {
                LongestTime = waiting;
            }

            if (waiting < ShortestTime)
            {
                ShortestTime = waiting;
            }
        }
        public void Simulate()
        {
            Queue <Customer> shortLine = null;
            Queue <Customer> Line      = null;

            if (EventPriorityQueue.IsEmpty())                  // Indicates simulation is finished running
            {
                CheckedOut = true;
                return;
            }

            if (EventPriorityQueue.Peek().Type == EVENTTYPE.ARRIVAL)               // If the event is an arrival
            {
                // Find shortest line and add registrant
                shortLine = GetShortLine();
                shortLine.Enqueue(EventPriorityQueue.Peek().CurrCustomer);

                // Increment if new largest queue found
                if (shortLine.Count > LargestQueue)
                {
                    LargestQueue++;
                }

                // Generate departure event if this customer is at the front of the line
                if (shortLine.Count == 1)
                {
                    LeaveEvent(shortLine.Peek());
                }


                // Event completely handled; remove the event and add to counter
                EventPriorityQueue.Dequeue();
                TotalArrivals++;
                TotalEvents++;
            }
            else                // If the event is a departure
            {
                // Get the line that registrant is about to leave
                for (int i = 0; i < InLine.Count; i++)
                {
                    if (InLine[i].Count > 0)
                    {
                        if (InLine[i].Peek().CustomerID == EventPriorityQueue.Peek().CurrCustomer.CustomerID)
                        {
                            Line = InLine[i];
                            break;
                        }
                    }
                }

                // Remove registrant from wait line
                Line.Dequeue();
                TotalCheckouts++;
                TotalEvents++;

                // If the wait line is not empty, generate a departure event for the next registrant
                if (Line.Count > 0)
                {
                    LeaveEvent(Line.Peek());
                }

                // Departure event handled; remove from Priority Queue
                EventPriorityQueue.Dequeue();
            }
        }         // end RunSimulation