ucxdsa 2026.6.28

Data Structures and Algorithms Source Code

UC Berkeley Extension - Data Structures and Algorithms Class

A collection of classes and functions for use in UC Berkeley Extension's Comp Sci X404.1: Data Structures and Algorithms Class.

This package is designed as an educational tool for students to learn and experiment with data structures and algorithms. It is written in Python with an emphasis on readability and clarity, rather than performance or optimization. Not intended for production use.

API Documentation

Command Line Installation

pip install ucxdsa

Updating an existing version of the DSA package

pip install --upgrade ucxdsa

Quick Usage Guide

from dsa.modulename import classname

To determine the version, enter the following in Python or Jupyter:

import dsa
print(dsa.version)

or from the terminal

pip show ucxdsa

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Revision History

2026.06.28

• Updated the implementation of Trie delete: returns True if word was successfully deleted

2026.02.13

• Updated HashSet constructor to accept an optional initial capacity (Thanks, John!)
• Added from_list() and to_list() methods to HashSet
• Added extract_min() and extract_max() as aliases for pop() in Heap/MinHeap
• Set DynamicArray minimum capacity to 10 when shrinking

2025.12.24

• Added from_dict() import methods to Graph classes
• Added more quick start documentation for the main data structures
• Thank you for your work, Rishab!

2025.12.9

• Renamed class dijkstras to dijkstra
• Cleaned up graph bugs and added adjacent_items() for weighted graphs (vertex and weight) pair
• adjacents() now returns a list of adjacent vertices only

2025.12.8

• Created Graph Factory class
• Major revisions to Graph class
  • Added and modified methods to Graph classes to take advantage of inheritance and follow CLRS closely
    • graph now has is_directed and is_weighted members (both default to False)
    • added size() - # of edges and order() -- # of vertices
    • added delete_vertex(), has_vertex() and get_weight()
    • renamed is_edge() to has_edge()
    • add_edge() now automatically adds directed or undirected edge based on the type graph type
  • Added graph_traversal module (moved all DFS and BFS methods to this module)
  • Any graph object now works on any graph algorithm
• Graph Draw now reads weighted and directed properties from graph object
• SinglyLinkedList and DoublyLinkedList now implements search and insert_after(). Removed insert() with index
• DoublyLinkedList now inherits from SinglyLinkedList and implements only methods that affect the contents of the list

2025.11.27

• Made sure that both vertices in add_edge() are included in the internal representation for the Adjacency List
• Adjacency Matrix self-loop vertices are now set to none
• Added to_dict() methods for Adjacency List and Adjacency Matrix classes
• Added is_weighted member for Adjacency List and Adjacency Matrix classes

2025.11.13

• Fixed Dijkstra’s algorithm implementation (shortest_path) to align with lecture slides
• Added contains method (in operator) to both Graph implementations for vertex existence checks
• Updated tests accordingly

2025.09.12

• Fixed bug when initial list is greater than 10 for Array, CircularArray and DynamicArray constructors

2025.09.02

• Added Hash Set
• Added data structure generators (not fully tested)
• Added equality testing for array, stack, queue, deque, linkedlist and heap classes
• Renamed Hashtable delete() to remove()
• Updated Dijkstra's algorithm implementation to follow lecture more closely

2025.07.17

• Added generators module -- functions to generate linear and random arrays, queues, stacks, tries, heaps, trees and graphs (warning: a work in progress)
• Hashtable updates
  • Allow non-strings for keys
  • Works with index operator [] and in operator
  • Added pop() method (thank you, Rishab!)
• Cleaned up some test cases (singly linked list, doubly linked list, stack, queue, hash table)

2025.07.05

• Added two new functions to sorttools: array_details() - returns the length, and the contents of an array/list and generate_almost_sorted_array()

2025.06.25

• Added boundary checking for shift_left() and shift_right() Array methods. Also, changed to accept only one argument starting argument. (Thanks for reporting this, Alejandro!)

2025.06.14

• Added iterative versions of insert and delete BST methods

2025.06.11

• Revised Trie Draw to draw circles instead of squares

2025.06.09

• Added queue-like synonyms for deque methods

2025.3.22

• Added CircularArray and CircularQueue classes
• SinglyLinkedList and DoublyLinkedList classes
  • Added separate delete_head() and delete_tail() methods
  • Changed behavior insert() so if index == count, performs an append()
• Changed behavior insert() in Array class so if index == count, performs an append()
• Queue and Heap classes
  • Refactored to_list() to raw_view()
  • Added to_ordered_list() to Queue class
  • Added to_sorted_list() method to Heap class
• Updated unit tests

2025.2.10

• Cleaned up comments
• Renamed df_traverse() to dfs_traverse() and bf_traverse() to bfs_traverse()

2025.2.9

• Refactored Dijkstra's algorithm code
• Added delete_edge() method to graphs
• Removed all duplicate add_edge() methods such as add_adjacent_vertex()
• Removed all add_directed_edge() methods and added directed argument to add_edge()
• Minor comment fixes

2025.1.31

• Fixed bug when DoublyLinkedList delete of the last index throws an Exception

2025.1.29

• Added is_sorted() in sorttools
• Fixed a bug when displaying a TreeNode in repr() format
• Update some modules to be more pyright compliant

2025.1.19

• Fixed bug in Queue to_list() method (thanks, Charles!)

2025.1.17

• Updated hash function code

2025.1.15

• Cleaned up README.md

2024.12.24

• Made default size for Trie graph larger
• Cleaned up Heap module
• Cleaned up Huffman module to use DSA data structures
• Added more tests
• Added more details to documentation

2024.12.22

• Created Github Pages access to documentation
• Added more details to documentation

2024.08.16.1

Fixed versioning issue. Can now determine version by typing:

import dsa
dsa.version

or

dsa.__version__

2024.08.16

moved Trie end_marker from an instance variable to a class variable (Trie.end_marker)

2024.08.15

dsa.draw

• new module to provide optional NetworkX graphics to:
• graphs
• tries
• trees
• heaps

dsa module

ran code through RUFF

dsa.graphs module

• Added vertices() method to AdjacencyListGraph, AdjacencyListWeightedGraph
• Dropped Vertex classes

dsa.tree

renamed Node class to TreeNode

2024.7.23

dsa.graphs module

• added is_edge() methods for AdjacencyMatrixGraph, AdjacencyMatrixWeightedGraph, AdjacencyListGraph, AdjacencyListWeightedGraph
• added index operator (returns a list of adjacent labels) for AdjacencyMatrixGraph, AdjacencyMatrixWeightedGraph
• cleaned up and refactored parameter names

2024.7.19

dsa.graphs module

• Added AdjacencyMatrixGraph, AdjacencyMatrixWeightedGraph, AdjacencyListGraph, AdjacencyListWeightedGraph
• Deprecated: Vertex, WeightedVertex

dsa.heap module

• Removed MinHeap option from the Heap class
• Added dedicated MinHeap class
• Added Priority Queue class

dsa package

Misc. code improvements, documentation updates and API consistency