Python3:二叉树的插入与删除

最新推荐文章于 2024-04-24 21:43:22 发布

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最新推荐文章于 2024-04-24 21:43:22 发布

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本文详细介绍了二叉搜索树的插入与删除操作，通过实例解析了如何使用右子树最小值替换待删除节点，并提供了Python实现代码，帮助读者深入理解二叉搜索树的动态维护过程。

看到一篇非常优秀的二叉树的插入与删除的博客，让我一下子明白了二叉树的删除。用的是为删除的节点赋右子树最小的值。然后删除右子树最小值的节点的方法

转载于：https://www.cnblogs.com/zuoyuan/p/3791801.html

class TreeNode:
    def __init__(self, x):
        self.val = x
        self.left = None
        self.right = None

class BinarySearchTree:
    # @param root, a tree node
    # @return a list of integers
    def Insert(self, root, x):
        if root == None:
            root = TreeNode(x)
        else:
            if x < root.val:
                root.left = self.Insert(root.left, x)
            if x > root.val:
                root.right = self.Insert(root.right, x)
        return root

    def Delete(self, root, x):
        if root:
            if x < root.val:
                root.left = self.Delete(root.left, x)
            elif x > root.val:
                root.right = self.Delete(root.right, x)
            elif root.left and root.right:
                tmp = self.FindMin(root.right)
                root.val = tmp.val
                root.right = self.Delete(root.right, root.val)
            else:
                tmp = root
                if root.left is None: root = root.right
                elif root.right is None: root = root.left
        return root

    def FindMin(self, root):
        if root:
            while root.left:
                root = root.left
        
        return root

    def preorder(self, root):
        if root:
            print root.val
            self.preorder(root.left)
            self.preorder(root.right)