C# PriorityQueue that allows repeated values implemented using SortedDictionary.

PriorityQueue.cs

    public class PriorityQueue<T>
    {
        readonly SortedDictionary<T, int> dict;

        public PriorityQueue()
        {
            dict = new SortedDictionary<T, int>();
        }

        public PriorityQueue(IComparer<T> comparer)
        {
            dict = new SortedDictionary<T, int>(comparer);
        }

        public PriorityQueue(IEnumerable<T> coll)
        {
            dict = new SortedDictionary<T, int>();
            AddMany(coll);
        }

        public PriorityQueue(IEnumerable<T> coll, IComparer<T> comparer)
        {
            dict = new SortedDictionary<T, int>(comparer);
            AddMany(coll);
        }

        public void AddMany(IEnumerable<T> coll)
        {
            foreach (var val in coll)
            {
                Add(val);
            }
        }

        public void Add(T value)
        {
            if (dict.ContainsKey(value)) dict[value]++;
            else dict[value] = 1;
        }

        public T Top()
        {
            return dict.Any() ? dict.First().Key : default;
        }

        public void Remove(T value)
        {
            var count = dict[value];
            if (count > 1) dict[value] = count - 1;
            else dict.Remove(value);
        }
    }