FragmentedArray

FragmentedArray.cs

 public class FragmentedArray<T> : IEnumerable<T>
    {
        private T[][] _fragments;
        private int _fragmentSize;
        public int Size { get; }

        public FragmentedArray(int size, int chunks = 3)
        {
            Size = size;
            _fragmentSize = size / chunks;
            _fragments = new T[chunks][];
            for (int i = 0; i < chunks; i++)
            {
                _fragments[i] = ArrayPool<T>.Shared.Rent(_fragmentSize);
            }
        }

        public T this[int index]    // Indexer declaration
        {
            //Will be round down, this is pretty handy
            get => _fragments[index / _fragmentSize][index % _fragmentSize];
            //Will be round down, this is pretty handy
            set => _fragments[index / _fragmentSize][index % _fragmentSize] = value;
        }

        public IEnumerable<T> AsEnumerable()
        {
            for (int i = 0; i < Size; i++)
            {
                yield return this[i];
            }
        }

        public IEnumerator<T> GetEnumerator()
        {
            return AsEnumerable().GetEnumerator();
        }

        IEnumerator IEnumerable.GetEnumerator()
        {
            return GetEnumerator();
        }
    }