Questions tagged [tree]
A tree is a graph in which there is exactly one path between any two nodes. It is often used as a hierarchical data structure.
889 questions
5
votes
2
answers
470
views
Weakly-Referencing Tree Structure in Python
For another project of mine, I decided that it would be handy to have a tree structure to dictate hierarchy between pieces of data, but I didn't want to unnecessarily keep that data alive if it would ...
2
votes
0
answers
77
views
Higher-order procedures for tree manipulation in SICP
I'm working my way through Structure and Interpretation of Computer Programs and got to exercises 2.27-2.28, reproduced here:
Exercise 2.27. Modify your reverse procedure of exercise 2.18 to
produce ...
- 21
6
votes
2
answers
84
views
STL style iterator template for arbitrary trees in C++20
In different code bases I regularly encounter tree data structures of different design and usually need to traverse it at some point. I finally got tired of writing yet another iterative traversal by ...
- 163
2
votes
1
answer
103
views
Numba implementation of AA Tree with rank and select operations
I've implemented an AA Tree (a type of self-balancing binary search tree) using Numba, a just-in-time compiler for Python. This implementation includes rank and select operations, which are useful for ...
- 21
7
votes
3
answers
785
views
Optimal Algorithm to Append and Access Tree Data
I have been studying intermediate or more advanced data structures in Python, one of which I've decided to try out is the Tree Data Structure. I've been studying the theories as well as the ...
- 177
5
votes
1
answer
134
views
Fast and low Memory Requiring Lookup Tree Library
Background
While working on solving the end game of the russian card game Durak I developed a library small_memory_tree to store the simulation results. You can try the game on my website Modern Durak ...
- 161
1
vote
0
answers
128
views
Rust implementation of a BTree
I'm studying rust, and I decided to implement a BTree as a way of learning the language.
Can anyone give me suggestions on the code?
As the language has no inheritance, and we must replace it with ...
- 174
5
votes
1
answer
145
views
Making sklearn's decision trees easier to traverse
scikit-learn's decision tree structure is difficult for me to navigate. I would prefer to have functionality like tree.left, ...
- 151
6
votes
3
answers
552
views
Leetcode: Largest Number
I was trying out leetcode's Largest Number.
As per the challenge's description:
Given a list of non-negative integers nums, arrange them such that
they form the largest number and return it. Since ...
- 351
2
votes
2
answers
704
views
Binary tree deepcopy using the Morris traversal in C
I need to perform a deep copy of a binary tree using the Morris traversal.
I think I managed to do it, that is the code below returns what I expect; however, I am not 100% sure I have covered every ...
- 121
2
votes
3
answers
178
views
Maximum Sum BST in a Binary Tree
I was trying to find the Maximum sum BST of a binary tree on LeetCode. While the Java code I have come up with, mostly seems right and is able to pass 55 out of the given 59 test cases too, the error ...
8
votes
3
answers
1k
views
Simple tree dictionary structure in C
I have developed a C library whose goal is to store strings in an easily searchable tree structure (which I have dubbed tree-dictionary). I come from a math background and I have been coding in Python ...
2
votes
1
answer
108
views
Semi-dynamic range minimum query (RMQ) tree in Java
Introduction
I have this semi-dynamic range minimum query (RMQ) tree in Java. It is called semi-dynamic due to the fact that it cannot be modified after it is constructed. However, the values ...
- 32.3k
3
votes
0
answers
67
views
Assign unique identifiers to binary matrices using a binary tree
Context
I want to build a transposition table where the game states are binary square matrices which size MATRIX_SIZE is known at compile time. Rather than storing ...
- 175
4
votes
1
answer
95
views
Hashing a fixed size binary stream with a tree structure in Rust
For a research project, I want to assign a unique identifier to a stream of bits. I can assume that all the streams will always have the same size.
Because of this nice property, my idea has been to ...
- 175
2
votes
2
answers
157
views
Binary search tree with Iterators
One more BST implementation with iterators added. Did not manage to find another implementation with iterators and it is my first attempt at implementing them so thought to check on your opinion:
<...
- 107
6
votes
2
answers
2k
views
Avoiding memory leaks and using pointers the right way in my binary search tree implementation - C++
I'm learning C++ and I wanted to test my knowledge by implementing a Binary Search Tree using struct (I know, I’m using C++ I should use classes but I want to keep ...
- 61
6
votes
2
answers
513
views
Optimizing a node search method given a 2-D spatial point
I have a tree-like structure called grid. I have designed it as a structured numpy array. Each element of grid is a tree-node. ...
- 63
3
votes
1
answer
153
views
Parallel semi-sequential bottom-up tree traversal algorithm
I'm trying to traverse a tree-like structure from the bottom-up, and in parallel. Due to some other constraints I also have to allow for thread counts that may be lower than the width of a given set ...
- 95
4
votes
1
answer
182
views
AutoComplete-Esque Tree
I've written a tree data structure that takes in input from the user, and stores the each letter based on the previous letter in the text. I'm not sure what this is called, but the closest I can find ...
- 10.8k
2
votes
1
answer
143
views
QuadTree implementation in c++
I'm new on C++ and OOP. I wrote the following QuadTree implementation (I didn't wrote the remove object part yet).
please take a look on it and provide feedback, mainly about C++ OOP design, ...
- 21
5
votes
1
answer
367
views
Port Node and TreeBuilder from Python to C++
I am trying to port a TreeBuilder Python class to C++, keeping the structure as close as possible to the original. Here is a simplified Python version: https://onlinegdb.com/I4dg0hCtg
The purpose of ...
- 63
3
votes
3
answers
463
views
Leet Code: 236. Lowest Common Ancestor of a Binary Tree. First version
Trying my hand at Leet 236
Given a binary tree, find the lowest common ancestor (LCA) of two given nodes in the tree.
According to the definition of LCA on Wikipedia: “The lowest common ancestor is ...
- 97.7k
4
votes
3
answers
557
views
Leet Code: 236. Lowest Common Ancestor of a Binary Tree
Trying my hand at Leet 236.
Given a binary tree, find the lowest common ancestor (LCA) of two given nodes in the tree.
According to the definition of LCA on Wikipedia: “The lowest common ancestor is ...
- 97.7k
3
votes
1
answer
415
views
Converting String to Binary Hash Tree
I've written a pretty basic algorithm to convert a string to a binary hash tree of its characters, where each character represents a leaf node. The hash tree itself is being stored in a vector.
If the ...
- 241
3
votes
2
answers
449
views
Implementation of a market that matches bids to offers
This is my task:
Each line in the file can be one of the following:
Updates to the limit order book in the following format:
...
- 31
2
votes
1
answer
150
views
function to group data by parent branches
I wrote this function to take database output like from PDO's fetchAll(PDO::FETCH_ASSOC) and turn it into a tree. For small datasets it works well. However, when ...
- 123
4
votes
3
answers
309
views
C++ B-Tree serialization/deserialization
Yesterday I wrote a serialization/deserialization for my B-Tree library.
Since the code for whole tree is too large to upload here, I'll upload only serialization/deserialization and node class ...
- 1,751
2
votes
1
answer
790
views
Traverse a list of tree nodes
I am wondering if there is a better way to traverse a list of trees.
Here is my current algorithm:
Collect the parent IDs in a Map
Traverse all the groups and find ones where their ID is not in the ...
- 718
1
vote
1
answer
99
views
Java - Select the maximum integers from sliding windows over an array
So I have the following algorithm. Given an array A[0 ... n - 1] and the window length w, compute all the windows ...
- 32.3k
2
votes
2
answers
426
views
Binary Search Tree implementation in C++ with templates
Im implementing a BST using templates and dynamic memory, here is my attempt:
This is the BSTNode.hh
...
- 279
3
votes
2
answers
91
views
Simple non balancing indexed binary search tree
The following code represents a simple indexed binary search tree of integers. The insert method inserts an int. The indexed lookup looks up the ith smallest element (0 indexed). I'm trying to write C+...
- 31
1
vote
1
answer
129
views
Decision Tree for classification tasks in Python
I've decided to implement the ID3 Decision Tree algorithm in Python based on what I've learned from George F. Luger's textbook on AI (and other secondary readings). As far as I know, the code is ...
- 357
2
votes
1
answer
2k
views
Replacing multiple substrings in C#
There is a String.Replace method in C# and it is 1-1 mapping replacing operation, i.e. single Unicode character / string source replaced with another single Unicode ...
- 7,575
3
votes
0
answers
350
views
Simple Merkle Tree
Discussion
I just started learning about Merkle Trees and wanted to get some practice by attempting to implement a very simple Merkle Tree.
The constructor for the tree takes some type of hash ...
- 1,875
1
vote
1
answer
89
views
Comparing two general LCA algorithms in Java
Now I have two algorithms solving a problem: given a general (multi-way) tree, and any array of node names, find the the node that is the deepest common ancestor.
...
- 32.3k
0
votes
1
answer
580
views
Populate TreeView with arbitrary depth from DataTable
I have a DataTable with id, parent, label columns and want to populate a TreeView with it.
I'm new to c# and as far as I understand, there is no ready solution for it, unlike some other languages.
So ...
- 11
3
votes
1
answer
543
views
Barnes-Hut \$n\$-body simulation (3D) in C++
I have implemented the Barnes-Hut algorithm for \$n\$-body-simulations (in this case "sort-of" 3D-gravity - see below). I'd appreciate any comments for improving my code (especially ...
- 131
1
vote
1
answer
234
views
Comparing a prefix tree against a HashSet of strings in Java
Here, I have made an attempt to find out whether a prefix tree is any more efficient than a simple java.util.HashSet<String>. See what I have:
...
- 32.3k
9
votes
0
answers
1k
views
Tree for PowerShell
For anyone reading this old question, this module has evolved and improved a lot since then. It has been fully rewritten in C# and uploaded to the PowerShell Gallery! If you would like to try it out:
<...
2
votes
1
answer
228
views
A Lowest Common Ancestor (LCA) Tree Algorithm
My implementation of the lowest common ancestor (LCA) algorithm for my tree data structure. I selected the non-preprocessed (naïve) implementation for this first implementation. Support for any number ...
0
votes
1
answer
86
views
is my Prim's MST implementation terse enough?
I did research because I want to learn Kruskal's and Prim's MSTs. I did research and after a solid understanding, I went to my textbook and got their libraries:
https://algs4.cs.princeton.edu/code/...
0
votes
1
answer
230
views
Leetcode 662. Maximum Width of Binary Tree Javascript FlatMap attempt - Time Limit Exceeded
Problem Statement:
Given the root of a binary tree, return the maximum width of the given
tree.
The maximum width of a tree is the maximum width among all levels.
The width of one level is defined as ...
2
votes
1
answer
144
views
Find ALL duplicate subtrees. using recursion
This is just a practice exercise, I'm trying to understand dynamic programming as deeply as I can. I solved this using recursion, though I am not sure if it will always work. If anyone could tell me a ...
- 121
1
vote
1
answer
1k
views
How does one write DFS in python with a Deque without reversed for Trees?
I have implemented a correct version of DFS (with comments explaining the implementation):
...
- 128
3
votes
1
answer
119
views
Building a tree containing all permutations of arithmetic expressions given some numbers
Given any series of numbers, for example 1,2,3,4,5 and given the arithmetic operands + - * / including parenthesis, what would be the most optimal way to build a tree that contains all permutations ...
- 133
3
votes
1
answer
133
views
AVL Tree in C Criticism
I have made an AVL tree in C and coded the basic functionality of insertion, deletion, and search. I would love some criticism on my implementation especially on the insertion and deletion section of ...
- 419
2
votes
1
answer
181
views
Monte Carlo Tree Search Optimization and Loss Prevention
I'm working on an implementation of Monte Carlo Tree Search in Swift.
It's not bad, but it could be better! I'm principally interested in making my algorithm:
faster (more iterations/second)
...
- 131
2
votes
1
answer
159
views
Haskell Dynamic Programming on a Tree
Here is my shot at Homework 8 of CIS-194 (from Spring '13). The problem is about a hierarchy of employees at a company (a tree), each node being of type Employee, ...
- 125
2
votes
1
answer
117
views
Pretty print a tree from minimal data input
I'm currently working on an uncrafting tool for minecraft and got a neat output working that shows all the materials needed in a tree. I wonder if the code used to print that tree could be improved ...
- 866