using System; using System.Collections.Generic; namespace DataStructures.SkipListSpace { public partial class SkipList : IEnumerable, ICollection where TKey : IComparable { [Serializable] private sealed class NullSkipNode : SkipNode where TKey : IComparable { public NullSkipNode(int level) : base(level) { } public bool Equals(SkipNode otherNode) { NullSkipNode otherNullNode = otherNode as NullSkipNode; if (otherNullNode == null) { return false; } return true; } } public void Add(TValue item) { throw new NotImplementedException(); } public void Clear() { throw new NotImplementedException(); } public bool Contains(TValue item) { throw new NotImplementedException(); } public void CopyTo(TValue[] array, int arrayIndex) { throw new NotImplementedException(); } public bool Remove(TValue item) { throw new NotImplementedException(); } public bool IsReadOnly { get; private set; } } }