Merge pull request #1 from sakapon/v1.0

v1.0.4

Author: sakapon

README.md

@@ -1,2 +1,74 @@
 # WBTrees
+[![license](https://img.shields.io/github/license/sakapon/WBTrees.svg)](LICENSE)
+[![NuGet](https://img.shields.io/nuget/v/WBTrees.svg)](https://www.nuget.org/packages/WBTrees/)
+[![NuGet](https://img.shields.io/nuget/dt/WBTrees.svg)](https://www.nuget.org/packages/WBTrees/)
+
 Provides a basic implementation of weight-balanced binary trees.
+
+The WBTrees library contains classes as follows:
+- A list by a weight-balanced binary tree, with all `O(log n)` basic operations
+  - `WBList<T>`
+- A set and a map by weight-balanced binary search trees, which can be accessed by index in `O(log n)` time
+  - `WBSet<T>`
+  - `WBMultiSet<T>`
+  - `WBMap<TKey, TValue>`
+  - `WBMultiMap<TKey, TValue>`
+
+All these trees are constructed from `Node<T>` objects.
+
+See [Wiki](https://github.com/sakapon/WBTrees/wiki) for more information.  
+This library is written in C#.
+You are welcome to port this to other languages.
+
+## Features
+
+### A List by a Weight-Balanced Binary Tree
+Provides the `WBList<T>` class as a list with all `O(log n)` basic operations.  
+You can also use a `WBList<T>` as a (high-grade) double-ended queue (deque).
+
+The following table compares time complexities of [`System.Collections.Generic.List<T>`](https://docs.microsoft.com/dotnet/api/system.collections.generic.list-1) and `WBList<T>`:
+| Operation | `List<T>` | `WBList<T>` |
+|:--|:-:|:-:|
+| Get by Index | `O(1)` | `O(log n)` |
+| Set by Index | `O(1)` | `O(log n)` |
+| Remove by Index | `O(n)` | `O(log n)` |
+| Insert by Index | `O(n)` | `O(log n)` |
+| Prepend | `O(n)` | `O(log n)` |
+| Add | `O(1)` | `O(log n)` |
+| Get All | `O(n)` | `O(n)` |
+
+### A Set and a Map by Weight-Balanced Binary Search Trees
+Provides the `WBSet<T>`, `WBMultiSet<T>`, `WBMap<TKey, TValue>` and `WBMultiMap<TKey, TValue>` classes, which can be accessed by index in `O(log n)` time. All these classes are derived from the `WBTreeBase<T>` class.  
+You can also use a `WBMultiSet<T>` or a `WBMultiMap<TKey, TValue>` as a priority queue with stable sorting or a double-ended priority queue.
+
+The following table compares time complexities of [`System.Collections.Generic.SortedSet<T>`](https://docs.microsoft.com/dotnet/api/system.collections.generic.sortedset-1) and `WBSet<T>`:
+| Operation | `SortedSet<T>` | `WBSet<T>` |
+|:--|:-:|:-:|
+| Get by Item | `O(log n)` | `O(log n)` |
+| Remove by Item | `O(log n)` | `O(log n)` |
+| Add | `O(log n)` | `O(log n)` |
+| Get by Index | `O(n)` | `O(log n)` |
+| Remove by Index | `O(n)` | `O(log n)` |
+| Get Index by Item | `O(n)` | `O(log n)` |
+| Get All | `O(n)` | `O(n)` |
+
+## Algorithm
+Both `WBList<T>` and `WBTreeBase<T>` are weight-balanced binary trees (not necessarily searchable by items).
+The `Node<T>` class contains the `Count` property that contributes to both self-balancing and fast access by index (order).
+
+## Target Frameworks
+- .NET 5
+- .NET Standard 2.0
+  - [.NET Core 2.0, .NET Framework 4.6.1, etc.](https://docs.microsoft.com/dotnet/standard/net-standard)
+
+## Setup
+The WBTrees library is published to [NuGet Gallery](https://www.nuget.org/packages/WBTrees/).
+Install the NuGet package via Visual Studio, etc.
+
+You can also [download a single source file here](downloads) for competitive programming, etc.
+
+## Usage
+See [Usage on Wiki](https://github.com/sakapon/WBTrees/wiki/Usage) for coding.
+
+## Release Notes
+- **v1.0.4** The first release.