BankSim/Program.cs

using System.Reflection.Metadata.Ecma335;

namespace MonteCarlo_Bank
{
    //! Because of dividing day into 11 parts (working hours)
    //! last served customer will probably overflow the hour
    //! and be served in the next hour, i will ignore this for now
    class Program
    {
        static void Main()
        {
            /* 
             * uint CustomersPerDay - 300 customers per day, 
             * uint MaxWaitTime - 15 min. maximal waiting time, 
             * uint MaxServiceTime - 15 min. maximal service time,
             * uint MinServiceTime - 5 min. minimal service time
             * uint MaxNumOfCounters is optional - Maximal number of opened counters
             * uint float[11] TimeCoef is optional - Coefficients for number of customers for each hour
             */
            _ = new BankSim(250, 15, 15, 5);
        }
    }

    class BankSim
    {
        public uint CustomersPerDay;
        public uint MaxWaitTime;
        public uint MaxServiceTime;
        public uint MinServiceTime;
        public uint MaxNumOfCounters;

        private float[] NumOfCustomersCoef = new float[] { 0.04f, 0.1f, 0.15f, 0.08f, 0.1f, 0.6f, 0.09f, 0.14f, 0.1f, 0.12f, 0.02f };
        private uint NumOfCustomers;

        private static Random random = new Random();
        private Dictionary<uint, KeyValuePair<uint, double>> result = new Dictionary<uint, KeyValuePair<uint, double>>();
        private List<KeyValuePair<uint, uint>> Customers = new List<KeyValuePair<uint, uint>>();

        public BankSim(uint CustomersPerDay, uint MaxWaitTime, uint MaxServiceTime, uint MinServiceTime, uint? MaxNumOfCounters = 250, float[]? TimeCoef = null) // Time is in minutes
        {
            // Set the parameters for the simulation
            this.CustomersPerDay = CustomersPerDay;
            this.MaxWaitTime = MaxWaitTime;
            this.MaxServiceTime = MaxServiceTime;
            this.MinServiceTime = MinServiceTime;
            this.MaxNumOfCounters = MaxNumOfCounters ?? 250;


            if (TimeCoef != null && TimeCoef.Length == 11) //! Remove check for 11 elements in array
            {
                NumOfCustomersCoef = TimeCoef;
            }

            Console.WriteLine("Running simulation with this parameters:");
            Console.WriteLine($"Total Number Of Customers: {this.CustomersPerDay}");
            Console.WriteLine($"Maximal Customer Waiting Time To Tolerate: {this.MaxWaitTime} min.");
            Console.WriteLine($"Maximal Service Time Of One Customer: {this.MaxServiceTime} min.");
            Console.WriteLine($"Minimal Service Time Of One Customer: {this.MinServiceTime} min.");
            Console.WriteLine($"Maximal Number Of Opened Counters: {this.MaxNumOfCounters} min.");
            Console.WriteLine();

            // Generate the number of customers for each hour and run simulation for each hour
            uint day_hour = 1;
            foreach (var DayTimeCoef in NumOfCustomersCoef)
            {
                Console.WriteLine($"Daytime: {day_hour}");
                CalcNumOfCustomersPerHour(DayTimeCoef);
                Customers = GenCustTimesOfArrivalAndService();

                // Run simulation for number of counters from 1 to number of customers
                List<double> satisfied_coefficient = new List<double>();
                for (int i = 1; i <= MaxNumOfCounters; ++i)
                {
                    //Console.WriteLine($"Number of counters: {i}");
                    List<uint> waiting_time_per_customer = RunSimulationHour(i);
                    satisfied_coefficient.Add(SatisfiedCustomers(waiting_time_per_customer));
                    //Console.WriteLine();
                }

                // Select number of counter with the satisfied coefficient
                int best_counter = satisfied_coefficient.IndexOf(satisfied_coefficient.Max()) + 1;
                Console.WriteLine($"Best number of counters: {best_counter}, satisfied customers {satisfied_coefficient.Max() * 100}%");
                result[day_hour] = new KeyValuePair<uint, double>((uint)best_counter, satisfied_coefficient.Max());

                Customers.Clear();
                Console.WriteLine();
                day_hour++;
            }

            Console.WriteLine("Simulation finished.");
            Console.WriteLine();
        }

        private uint CalcNumOfCustomersPerHour(float DayTime)
        {
            // Calculate the number of customers for each hour of the day
            NumOfCustomers = (uint)(CustomersPerDay * DayTime);
            return NumOfCustomers;
        }

        private List<KeyValuePair<uint, uint>> GenCustTimesOfArrivalAndService()
        {
            // Generate random times of arrival for each customer (from one to 60 minutes)
            for (uint i = 0; i < NumOfCustomers; ++i)
            {
                uint Time = (uint)random.Next(1, 60);
                uint ServiceTime = (uint)random.Next((int)MinServiceTime, (int)MaxServiceTime);
                Customers.Add(new KeyValuePair<uint, uint>(Time, ServiceTime));
            }

            return Customers;
        }

        private List<uint> RunSimulationHour(int counters)
        {
            Customers.Sort((x, y) => x.Key.CompareTo(y.Key));

            // Queue for waiting customers
            Queue<(uint arrivalTime, uint serviceTime, uint waitingTime)> waitingQueue = new Queue<(uint, uint, uint)>();

            // Track counters
            List<(uint endTime, uint arrivalTime, uint waitingTime)> activeCounters = new List<(uint, uint, uint)>();

            List<uint> waiting_time = new List<uint>();
            for (uint i = 0; i < 10000; ++i) //! Optimize this number somehow maybe
            {
                // Add new arriving customers to waiting queue
                foreach (var customer in Customers.FindAll(x => x.Key == i))
                {
                    waitingQueue.Enqueue((customer.Key, customer.Value, 0));
                }

                // Free up counters where customers have finished service
                activeCounters.RemoveAll(counter => counter.endTime == i);

                // Assign waiting customers to available counters
                while (activeCounters.Count < counters && waitingQueue.Count > 0)
                {
                    var (arrivalTime, serviceTime, waitingTime) = waitingQueue.Dequeue();
                    uint startTime = Math.Max(i, arrivalTime);
                    uint endTime = startTime + serviceTime;
                    activeCounters.Add((endTime, arrivalTime, waitingTime));

                    //Console.WriteLine($"customer {arrivalTime}-{endTime} | served at {startTime} min. for {serviceTime} min. | waiting {waitingTime}");
                    waiting_time.Add(waitingTime);
                }

                // Increase waiting time for customers still in queue
                int queueSize = waitingQueue.Count;
                for (int j = 0; j < queueSize; j++)
                {
                    var customer = waitingQueue.Dequeue();
                    waitingQueue.Enqueue((customer.arrivalTime, customer.serviceTime, customer.waitingTime + 1));
                }

            }
            return waiting_time;
        }

        private double SatisfiedCustomers(List<uint> waiting_times)
        {
            uint unsatisfied = 0;
            foreach (var time in waiting_times)
            {
                if (time > MaxWaitTime)
                {
                    unsatisfied++;
                }
            }

            // Calculate the number of satisfied customers
            uint satisfied = (uint)(waiting_times.Count() - unsatisfied);

            // Return the percentage of satisfied customers as a value between 0 and 1
            return (double)satisfied / waiting_times.Count();
        }
    }
}