如何生成尽可能不平衡的AVL树?

发布于 2024-12-28 23:13:03 字数 122 浏览 2 评论 0原文

我在一些论文中看到这一点,有人认为当我们删除 AVL 树的节点时最多可以有 log(n) 次旋转。我相信我们可以通过生成尽可能不平衡的 AVL 树来实现这一目标。问题是如何做到这一点。这对我研究移除旋转的事情有很大帮助。非常感谢!

I saw this in some paper and someone argued that there can be at most log(n) times rotation when we delete a node of an AVL tree. I believe we can achieve this by generating an AVL tree as lopsided as possible. The problem is how to do this. This will help me a lot about researching the removal rotation thing. Thanks very much!

如果你对这篇内容有疑问,欢迎到本站社区发帖提问 参与讨论,获取更多帮助,或者扫码二维码加入 Web 技术交流群。

扫码二维码加入Web技术交流群

发布评论

需要 登录 才能够评论, 你可以免费 注册 一个本站的账号。

评论(1

噩梦成真你也成魔 2025-01-04 23:13:03

如果你想制作一棵最大不平衡的 AVL 树,你需要寻找斐波那契数列树,归纳定义如下:

  • 0阶斐波那契树为空。
  • 1 阶斐波那契树是单个节点。
  • n + 2 阶斐波那契树是一个节点,其左子节点是 n 阶斐波那契树,右子节点是 n + 1 阶斐波那契树。

例如,这是一个 5 阶斐波那契树:

在此处输入图像描述

斐波那契树代表最大值AVL 树可以具有的倾斜量,因为如果平衡因子更加不平衡,每个节点的平衡因子将超过 AVL 设定的限制树。

您可以使用这个定义非常容易地生成最大不平衡的 AVL 树:

function FibonacciTree(int order) {
    if order = 0, return the empty tree.
    if order = 1, create a single node and return it.
    otherwise:
        let left  = FibonacciTree(order - 2)
        let right = FibonacciTree(order - 1)
        return a tree whose left child is "left" and whose right child is "right."

希望这会有所帮助!

If you want to make a maximally lopsided AVL tree, you are looking for a Fibonacci tree, which is defined inductively as follows:

  • A Fibonacci tree of order 0 is empty.
  • A Fibonacci tree of order 1 is a single node.
  • A Fibonacci tree of order n + 2 is a node whose left child is a Fibonacci tree of order n and whose right child is a Fibonacci tree of order n + 1.

For example, here's a Fibonacci tree of order 5:

enter image description here

The Fibonacci trees represent the maximum amount of skew that an AVL tree can have, since if the balance factor were any more lopsided the balance factor of each node would exceed the limits placed by AVL trees.

You can use this definition to very easily generate maximally lopsided AVL trees:

function FibonacciTree(int order) {
    if order = 0, return the empty tree.
    if order = 1, create a single node and return it.
    otherwise:
        let left  = FibonacciTree(order - 2)
        let right = FibonacciTree(order - 1)
        return a tree whose left child is "left" and whose right child is "right."

Hope this helps!

~没有更多了~
我们使用 Cookies 和其他技术来定制您的体验包括您的登录状态等。通过阅读我们的 隐私政策 了解更多相关信息。 单击 接受 或继续使用网站,即表示您同意使用 Cookies 和您的相关数据。
原文