Data - more nodes!

Data Structure

A systematic way of organizing and accessing data.

Algorithm

A generic step-by-step set of instructions for solving a problem.

Abstract Data Type (ADT)

A theoretical model of a data structure that specifies what operations are allowed but not how they are implemented.

Big O Notation

Describes the worst-case complexity of an algorithm.

O(1)

Constant time – operations take the same time regardless of input size.

O(n)

Linear time – performance scales directly with input size.

O(n²)

Quadratic time – performance scales with the square of input size.

O(log n)

Logarithmic time – performance scales logarithmically with input size.

O(bⁿ)

Exponential time – performance doubles with each additional input.

O(n!)

Factorial time – performance grows extremely fast with input size.

Inheritance

A class can inherit attributes and methods from another class.

Constructor (init)

A special function that initializes an object.

Access Control

Refers to the visibility of variables; public, protected, and private attributes.

Stack

A linear data structure that follows the Last In, First Out (LIFO) principle.

Queue

A linear data structure that follows the First In, First Out (FIFO) principle.

Deque

A data structure that allows insertions and deletions from both the front and back (double-ended queue).

Node

A fundamental building block of linked data structures, consisting of a data field and a reference to the next node.

push(item)

Adds an item to the top of the stack.

pop()

Removes and returns the top item from the stack.

peek()

Returns the top item from the stack without removing it.

enqueue(item)

Adds an item to the back of the queue.

dequeue()

Removes and returns the front item from the queue.

add_front(item)

Adds an item to the front of the deque.

add_rear(item)

Adds an item to the back of the deque.

remove_front()

Removes and returns the front item from the deque.

remove_rear()

Removes and returns the back item from the deque.

self Keyword

Refers to the instance of the class.

str Method

Defines how an object is represented as a string.