我想知道人们如何在不使用基类库实现的情况下在 C# 中实现以下数据结构：-
- 链表
- 哈希表
- 二叉搜索树
- 红黑树
- B树
- 二项式堆
- 斐波那契堆
以及人们能想到的任何其他基本数据结构！
我很好奇，因为我想提高对这些数据结构的理解，很高兴看到 C# 版本而不是互联网上的典型 C 示例！
kronoz
问问题
4478 次
5 回答
4
这是一个通用的二叉搜索树。我唯一没有做的是实现 IEnumerable<T> 以便您可以使用枚举器遍历树。然而，这应该是相当直截了当的。
特别感谢 Scott Mitchel 的 BSTTree 文章，我将其作为删除方法的参考。
节点类：
class BSTNode<T> where T : IComparable<T>
{
private BSTNode<T> _left = null;
private BSTNode<T> _right = null;
private T _value = default(T);
public T Value
{
get { return this._value; }
set { this._value = value; }
}
public BSTNode<T> Left
{
get { return _left; }
set { this._left = value; }
}
public BSTNode<T> Right
{
get { return _right; }
set { this._right = value; }
}
}
和实际的树类：
class BinarySearchTree<T> where T : IComparable<T>
{
private BSTNode<T> _root = null;
private int _count = 0;
public virtual void Clear()
{
_root = null;
_count = 0;
}
public virtual int Count
{
get { return _count; }
}
public virtual void Add(T value)
{
BSTNode<T> newNode = new BSTNode<T>();
int compareResult = 0;
newNode.Value = value;
if (_root == null)
{
this._count++;
_root = newNode;
}
else
{
BSTNode<T> current = _root;
BSTNode<T> parent = null;
while (current != null)
{
compareResult = current.Value.CompareTo(newNode.Value);
if (compareResult > 0)
{
parent = current;
current = current.Left;
}
else if (compareResult < 0)
{
parent = current;
current = current.Right;
}
else
{
// Node already exists
throw new ArgumentException("Duplicate nodes are not allowed.");
}
}
this._count++;
compareResult = parent.Value.CompareTo(newNode.Value);
if (compareResult > 0)
{
parent.Left = newNode;
}
else
{
parent.Right = newNode;
}
}
}
public virtual BSTNode<T> FindByValue(T value)
{
BSTNode<T> current = this._root;
if (current == null)
return null; // Tree is empty.
else
{
while (current != null)
{
int result = current.Value.CompareTo(value);
if (result == 0)
{
// Found the corrent Node.
return current;
}
else if (result > 0)
{
current = current.Left;
}
else
{
current = current.Right;
}
}
return null;
}
}
public virtual void Delete(T value)
{
BSTNode<T> current = this._root;
BSTNode<T> parent = null;
int result = current.Value.CompareTo(value);
while (result != 0 && current != null)
{
if (result > 0)
{
parent = current;
current = current.Left;
}
else if (result < 0)
{
parent = current;
current = current.Right;
}
result = current.Value.CompareTo(value);
}
if (current == null)
throw new ArgumentException("Cannot find item to delete.");
if (current.Right == null)
{
if (parent == null)
this._root = current.Left;
else
{
result = parent.Value.CompareTo(current.Value);
if (result > 0)
{
parent.Left = current.Left;
}
else if (result < 0)
{
parent.Right = current.Left;
}
}
}
else if (current.Right.Left == null)
{
if (parent == null)
this._root = current.Right;
else
{
result = parent.Value.CompareTo(current.Value);
if (result > 0)
{
parent.Left = current.Right;
}
else if (result < 0)
{
parent.Right = current.Right;
}
}
}
else
{
BSTNode<T> furthestLeft = current.Right.Left;
BSTNode<T> furthestLeftParent = current.Right;
while (furthestLeft.Left != null)
{
furthestLeftParent = furthestLeft;
furthestLeft = furthestLeft.Left;
}
furthestLeftParent.Left = furthestLeft.Right;
furthestLeft.Left = current.Left;
furthestLeft.Right = current.Right;
if (parent != null)
{
result = parent.Value.CompareTo(current.Value);
if (result > 0)
{
parent.Left = furthestLeft;
}
else if (result < 0)
{
parent.Right = furthestLeft;
}
}
else
{
this._root = furthestLeft;
}
}
this._count--;
}
}
}
于 2008-09-07T14:18:26.930 回答
2
对于您提到的数据结构，我会推荐两个资源：首先，有 .NET Framework 源代码（信息可以在 ScottGu 的博客上找到）。
另一个有用的资源是在 Codeplex 上找到的 Wintellect 的 Power Collections。
希望这可以帮助！
于 2008-09-07T11:49:22.090 回答
2
“提供标准 .NET 框架中未实现的通用数据结构和算法的类库。”
于 2009-01-19T21:00:23.943 回答
1
您也可以查看Microsoft 参考源
于 2008-09-08T09:35:07.040 回答