/* This program is a queue that dequeues packages by their priority (Low, Medium, High). Fully Object Oriented approach with encapsulation */ using System; using System.Collections.Generic; using System.Text; namespace SoloLearn { class Program { static void Main(string[] args) { Random generator = new Random(); int amount = generator.Next(5, 24); PriorityQueue queue = new PriorityQueue(); // we create packages here Console.WriteLine("Creating Packages..."); for (int i=0; i<=amount; i++){ Package pack = PackageFactory.CreatePackage(); queue.Enqueue(pack); Console.WriteLine("Package Created with priority: {0}", pack.priority); } Console.WriteLine("Packages Created!\n\n"); // display queue registry Console.WriteLine("High Priority Packages: {0}", queue.Registry(Priority.High)); } } enum Priority{ Low, Medium, High } interface IPrioritizable{ Priority priority {get;} } class PriorityQueue where T : IPrioritizable { // Three queues that we use private Queue _queueHigh = new Queue(); private Queue _queueMedium = new Queue(); private Queue _queueLow = new Queue(); // specialized enqueue method that checks the item`s priority public void Enqueue(T item) { // checks item priority and enqueues it accordingly switch (item.priority) { case Priority.High: _queueHigh.Enqueue(item); break; case Priority.Medium: _queueMedium.Enqueue(item); break; case Priority.Low: _queueLow.Enqueue(item); break; default: throw new ArgumentOutOfRangeException( item.priority.ToString(), "; bad priority in PriorityQueue.Enqueue" ); } } public T Dequeue() { Queue topQueue = TopQueue(); if (topQueue.Count > 0 && topQueue != null){ return topQueue.Dequeue(); } return default(T); } public Queue Registry(Priority priority){ switch (priority) { case Priority.High: return _queueHigh; case Priority.Medium: return _queueMedium; case Priority.Low: return _queueLow; default: throw new ArgumentOutOfRangeException(); } } private Queue TopQueue() { if (_queueHigh.Count > 0){ return _queueHigh; } else if (_queueMedium.Count > 0){ return _queueMedium; } else{ return _queueLow; } } } class Package : IPrioritizable { private Priority _priority; static int count; private string idOfReciever; public string contents; private string address; public Package(Priority priority) { this._priority = priority; Package.count++; } public Priority priority{ get{ return _priority; } } } static class PackageFactory { private static Random randgen = new Random(); public static Package CreatePackage() { int random = randgen.Next(3); return new Package((Priority)random); } } }

Priority Queue (Package Checkout, Generics)