BinarySearchTree | 二叉搜索树 中序、先序、后序遍历 搜索树中的值 | Dataset library

I feel like a noob for asking this question but in my current driver, I've printed out a preorder of a tree using an iterator to a text file successfully. I don't know how to print my recursive methods because I can't just put them into a println statement since they are void methods. I know that I'm supposed to make the method take the writer as a parameter but don't know how to do it (Last couple println statements of driver). Any help is appreciated!

Driver:

I am trying to figure out a way to compute the sum and the total number of nodes in a BST, Binary Search Tree. I assume that the values of the nodes are all numerical. I have made the following code and tried different ways, but everything leads up to missing root or similar missing things.

I'm trying to recursively implement a binary search tree in python, using a Node class and Tree class.

The doubt is concerning the final deletion step (in the final else statement) and how the parent nodes reference to child node is reassigned. The code is from the book Data structures and Algorithm analysis in C++ by Mark Allen Weiss. Reference of entire code: https://users.cis.fiu.edu/~weiss/dsaa_c++3/code/BinarySearchTree.h

As I understand the program, node pointer t points to the node that is to be deleted.
This pointer is then copied to node pointer oldNode and then t points to a child node if any (in this case a right child due to findMin).
The node pointed by oldNode is then deleted.
But how is the parent nodes pointer (parent->left or parent->right of the parent of node pointed to by oldNode) assigned to point to the child node pointed to by t?
Is it happening with the conditional assignment of t?

Here's the method:

I'm creating a basic binary search tree program where the nodes have to be strings however, I keep getting this error: 'builtins.AttributeError: 'NoneType' object has no attribute 'addNode'

I'm a bit confused because I thought you had to declare the children nodes as None. My code is below (please excuse the messiness and extra print statements):

I am trying to implement a binary search tree in Rust. The remove method uses unsafe Rust code and I want to write the equivalent safe Rust code.

I am having problems as self is a mutable reference and when destructuring it using match statement, the compiler complains because I cannot reassign to it as it is already borrowed.

This question may be similar to this one but there is slight nuance. I would like to understand how the recursion works when there are two recursion calls one underneath the other.

Consider the following tree traversal for preorder.

. [Ref: educative.io]

I have added few print statement to understand how each recursion call is working:

I have a class:

I would like to ask for a bit of assistance. I have a polynomial object that I already build mathematical equalities for it. So for example, if I have 3X^3+2X^2+X and 6X^3+5X^2+4X, then P2>P1, all is good until now.

All these objects are put inside a BinarySearchTree, and with a def, I need to take them out in-order on an array, so as an example: 0 3X^3+2X^2+X 18 Would release [0, 18, 3X^3+2X^2+X] I managed to make an array of all the polynoms in it, but I can't figure out how to either send them directly into the array already arranged correctly, or how do I sort the functions within the array?