POS terminal problem in 1 line of code

Program.cs

using System;
using System.Collections;
using System.Collections.Generic;
using System.Collections.Specialized;
using System.Linq;
using System.Text;
using Microsoft.Practices.Unity;

namespace ConsoleApplication1
{
   public class Program
   {
		public class Product
		{
			public decimal PriceForOne { get; set;  }
			public int Pack { get; set;  }
			public decimal PriceForPack { get; set; }
			public string Code { get; set; }
		}
      static void Main(string[] args)
      {
      	Func<String[], decimal> POSTerminal = inp =>
      	                                 (
      	                                 	from item in
      	                                 		from code in inp
      	                                 		group code by code
      	                                 		into g
      	                                 		select new {code = g.Key, count = g.Count()}
      	                                 	join catItem in
      	                                 		new[] //  Catalog
      	                                 			{
      	                                 				new Product {Code = "A", PriceForOne = 1.25m, Pack = 3, PriceForPack = 3m},
      	                                 				new Product {Code = "B", PriceForOne = 4.25m},
      	                                 				new Product {Code = "C", PriceForOne = 1m, Pack = 6, PriceForPack = 5m},
      	                                 				new Product {Code = "D", PriceForOne = 0.75m},
      	                                 			}
      	                                 		on item.code equals catItem.Code
      	                                 	select
      	                                 		catItem.Pack > 1
      	                                 			? item.count/catItem.Pack*catItem.PriceForPack +
      	                                 			  (item.count%catItem.Pack)*catItem.PriceForOne
      	                                 			: item.count*catItem.PriceForOne
      	                                 ).Sum();
			Console.WriteLine("13.25=" + POSTerminal(new[] { "A", "B", "C", "D", "A", "B", "A" }));
			Console.WriteLine("6=" + POSTerminal(new[] { "C", "C", "C", "C", "C", "C", "C" }));
			Console.WriteLine("7.25=" + POSTerminal(new[] { "A", "B", "C", "D" }));

      }
   }
}