using System.Collections.Generic;

public class PriorityQueue<T>
{
    // The items and priorities.
    List<T> Values = new List<T>();
    List<int> Priorities = new List<int>();

    // Return the number of items in the queue.
    public int NumItems
    {
        get
        {
            return Values.Count;
        }
    }

    // Add an item to the queue.

    public void AddAt(int index,T new_value, int new_priority)
    {
        Values.Insert(index, new_value);
        Priorities.Insert(index, new_priority);
    }

    public void Enqueue(T new_value, int new_priority)
    {
        var index = 0;
        foreach (var item in Priorities)
        {
            if (item < new_priority) index++;
            else break;
        }
        Values.Insert(index,new_value);
        Priorities.Insert(index,new_priority);
    }

    // Remove the item with the largest priority from the queue.
    public KeyValuePair<T,int> Dequeue()
    {
        // Find the hightest priority.
        var best_index = 0;

        // Return the corresponding item.
        var top_value = Values[best_index];
        var top_priotiy = Priorities[best_index];
        // Remove the item from the lists.
        Values.RemoveAt(best_index);
        Priorities.RemoveAt(best_index);
        return new KeyValuePair<T,int>(top_value,top_priotiy);
    }
}