Data Structures

List of pages of notes on the wiki related to data structures:

Elementary Data Structures

Arrays

• array-based data structures, storage, and algorithms
• lower-level structure that can be implemented by many higher-level data structures
• Python has a built-in array-based list() type, everything (including integers) is reference-based - Arrays/Python
• Java has Array type, size must be known at creation time - Arrays/Java
• Can implement a Python list type in Java - see Arrays/Java/PythonList
• Many data structures below can be implemented under the hood as array-based or linked structure based

StacksQueues

• Stacks, queues, and deques are important structures for O(1) access to front/back, order in determines order out

Lists

• Lists have two main implementations - array-based lists (in Python, this is a natural place to start, due to Python's built-in list type) or object- and link-based (in Java, this is more natural due to the way the language principally focuses on objects).
• Linked Lists can be implemented in either Python or Java - see Linked Lists/Python or Linked Lists/Java
• ArrayLists are a type in Java but are also similar to the array-based list data structure built into Python

Trees

• Binary Trees
• Binary Trees/Python
• Binary Search Trees

Dictionaries