using System;

using System.Collections.Generic;

​

namespace OrderApp

{

    class Program

    {

        static void Main(string[] args)

        {

            var order = new Order();

            order.CustomerName = "Alice";

            order.Items = new List<OrderItem>();

            order.Items.Add(new OrderItem() { Name = "Book", Price = 10.5, Quantity = 1 });

            order.Items.Add(new OrderItem() { Name = "Pen", Price = 2, Quantity = 5 });

            order.Items.Add(new OrderItem() { Name = "Notebook", Price = 4, Quantity = 2 });

            order.Items.Add(new OrderItem() { Name = "Stapler", Price = 6, Quantity = 1 });

            order.Items.Add(new OrderItem() { Name = "Eraser", Price = 1, Quantity = 3 });

            order.Items.Add(new OrderItem() { Name = "Ruler", Price = 3, Quantity = 2 });

​

            var processor = new OrderProcessor();

            processor.Process(order);

        }

    }

​

    public class OrderProcessor

    {

        public void Process(Order order)

        {

            if (order.CustomerName == null || order.CustomerName == "")

            {

                Console.WriteLine("Customer name is required.");

                return;

            }

​

            double total = 0;

​

            foreach (var item in order.Items)

            {

                total += item.Price * item.Quantity;

            }

​

            if (order.Items.Count > 5)

            {

                total = total - (total * 0.1); // Apply 10% discount

            }

​

            Console.WriteLine("Order processed for " + order.CustomerName);

            Console.WriteLine("Total: $" + total);

        }

    }

​

    public class Order

    {

        public string CustomerName;

        public List<OrderItem> Items;

    }

​

    public class OrderItem

    {

        public string Name;

        public double Price;

        public int Quantity;

    }

}