using System;

namespace DailyProgrammer_Practial_201
{
    internal class Program
    {
        private static void Main()
        {
            var myQ = new PriorityQueue();

            myQ.Enqueue("Knife A5 B10", 5, 10);
            myQ.Enqueue("Fork A15 B7", 15, 7);
            myQ.Enqueue("Spoon A0.9 B11", 0.9, 11);
            myQ.Enqueue("Glass A13.2 B22", 13.2, 22);
            myQ.Enqueue("Plate A5 B6", 5, 6);
            Console.WriteLine(myQ.DequeueA());
            Console.WriteLine(myQ.DequeueA());
            Console.WriteLine(myQ.DequeueB());
            Console.WriteLine(myQ.DequeueB());
            Console.WriteLine(myQ.DequeueA());
        }
    }

    internal class PriorityQueue
    {
        private QueueItem _first;

        public void Enqueue(string itemName, double priorityValueA, double priorityValueB)
        {
            var thisItem = new QueueItem(itemName, priorityValueA, priorityValueB);
            if (_first == null) _first = thisItem;
            else
            {
                var tmp = _first;
                while (tmp.NextQueueItem != null)
                {
                    tmp = tmp.NextQueueItem;
                }
                tmp.NextQueueItem = thisItem;
            }
        }

        public string DequeueA()
        {
            if (_first == null)
            {
                return null;
            }
            var highestPriorityItem = _first;
            QueueItem beforeHighestPriorityQueueItem = null;
            var tmpQueueItem = _first;
            QueueItem lastQueueItem = null;


            while (tmpQueueItem != null)
            {
                if (tmpQueueItem.A > highestPriorityItem.A)
                {
                    beforeHighestPriorityQueueItem = lastQueueItem;
                    highestPriorityItem = tmpQueueItem;
                }
                lastQueueItem = tmpQueueItem;
                tmpQueueItem = tmpQueueItem.NextQueueItem;
            }
            if (highestPriorityItem.NextQueueItem != null && beforeHighestPriorityQueueItem != null)
            {
                beforeHighestPriorityQueueItem.NextQueueItem = highestPriorityItem.NextQueueItem;
            }
            else if (beforeHighestPriorityQueueItem != null)
            {
                beforeHighestPriorityQueueItem.NextQueueItem = null;
            }
            else
            {
                _first = highestPriorityItem.NextQueueItem;
            }
            return highestPriorityItem.Name;
        }

        public string DequeueB()
        {
            if (_first == null)
            {
                return null;
            }
            var highestPriorityItem = _first;
            QueueItem beforeHighestPriorityQueueItem = null;
            var tmpQueueItem = _first;
            QueueItem lastQueueItem = null;


            while (tmpQueueItem != null)
            {
                if (tmpQueueItem.B > highestPriorityItem.B)
                {
                    beforeHighestPriorityQueueItem = lastQueueItem;
                    highestPriorityItem = tmpQueueItem;
                }
                lastQueueItem = tmpQueueItem;
                tmpQueueItem = tmpQueueItem.NextQueueItem;
            }
            if (highestPriorityItem.NextQueueItem != null && beforeHighestPriorityQueueItem != null)
            {
                beforeHighestPriorityQueueItem.NextQueueItem = highestPriorityItem.NextQueueItem;
            }
            else if (beforeHighestPriorityQueueItem != null)
            {
                beforeHighestPriorityQueueItem.NextQueueItem = null;
            }
            else
            {
                _first = highestPriorityItem.NextQueueItem;
            }
            return highestPriorityItem.Name;
        }

        public int Count()
        {
            var count = 0;
            var tmp = _first;
            while (tmp != null)
            {
                count++;
                tmp = tmp.NextQueueItem;
            }
            return count;
        }

        public void Clear()
        {
            _first = null;
        }

        private class QueueItem
        {
            public readonly double A;
            public readonly double B;
            public readonly string Name;
            public QueueItem NextQueueItem { get; set; }

            public QueueItem(string name, double a, double b)
            {
                Name = name;
                A = a;
                B = b;
            }
        }
    }
}