big-o-complexity.cheatsheet

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#-# Big-O complexities for common algorithms
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#-# Data Structure Operations

Data Structure Time Complexity Space Complexity

                    Average                                       Worst                                          Worst
                    -------                                       -----                                          -----
                    Access     Search     Insertion   Deletion    Access     Search     Insertion    Deletion
                    ------     ------     ---------   --------    ------     ------     ---------    --------

Array O(1) O(n) O(n) O(n) O(1) O(n) O(n) O(n) O(n)
Stack O(n) O(n) O(1) O(1) O(n) O(n) O(1) O(1) O(n)
Singly-Linked List O(n) O(n) O(1) O(1) O(n) O(n) O(1) O(1) O(n)
Doubly-Linked List O(n) O(n) O(1) O(1) O(n) O(n) O(1) O(1) O(n)
Skip List O(log(n)) O(log(n)) O(log(n)) O(log(n)) O(n) O(n) O(n) O(n) O(n log(n))
Hash Table - O(1) O(1) O(1) - O(n) O(n) O(n) O(n)
Binary Search Tree O(log(n)) O(log(n)) O(log(n)) O(log(n)) O(n) O(n) O(n) O(n) O(n)
Cartesian Tree - O(log(n)) O(log(n)) O(log(n)) - O(n) O(n) O(n) O(n)
B-Tree O(log(n)) O(log(n)) O(log(n)) O(log(n)) O(log(n)) O(log(n)) O(log(n)) O(log(n)) O(n)
Red-Black Tree O(log(n)) O(log(n)) O(log(n)) O(log(n)) O(log(n)) O(log(n)) O(log(n)) O(log(n)) O(n)
Splay Tree - O(log(n)) O(log(n)) O(log(n)) - O(log(n)) O(log(n)) O(log(n)) O(n)
AVL Tree O(log(n)) O(log(n)) O(log(n)) O(log(n)) O(log(n)) O(log(n)) O(log(n)) O(log(n)) O(n)

#-# Array Sorting Algorithms

Algorithm Time Complexity Space Complexity

                    Best          Average         Worst           Worst
                    ----          -------         -----           -----

Quicksort O(n log(n)) O(n log(n)) O(n^2) O(log(n))
Mergesort O(n log(n)) O(n log(n)) O(n log(n)) O(n)
Timsort O(n) O(n log(n)) O(n log(n)) O(n)
Heapsort O(n log(n)) O(n log(n)) O(n log(n)) O(1)
Bubble Sort O(n) O(n^2) O(n^2) O(1)
Insertion Sort O(n) O(n^2) O(n^2) O(1)
Selection Sort O(n^2) O(n^2) O(n^2) O(1)
Shell Sort O(n) O((nlog(n))^2) O((nlog(n))^2) O(1)
Bucket Sort O(n+k) O(n+k) O(n^2) O(n)
Radix Sort O(nk) O(nk) O(nk) O(n+k)

#-# Graph Operations

Node / Edge Management Time complexity

                    Storage       Add Vertex    Add Edge      Remove Vertex   Remove Edge   Query
                    -------       ----------    --------      -------------   -----------   -----

Adjacency list O(|V|+|E|) O(1) O(1) O(|V|+|E|) O(|E|) O(|V|)
Incidence list O(|V|+|E|) O(1) O(1) O(|E|) O(|E|) O(|E|)
Adjacency matrix O(|V|^2) O(|V|^2) O(1) O(|V|^2) O(1) O(1)
Incidence matrix O(|V|⋅|E|) O(|V|⋅|E|) O(|V|⋅|E|) O(|V|⋅|E|) O(|V|⋅|E|) O(|E|)

#-# Heap Operations

Type Time Complexity

                    Heapify   Find Max  Extract Max   Increase Key  Insert     Delete     Merge
                    -------   --------  -----------   ------------  ------     ------     -----

Linked List (sorted) - O(1) O(1) O(n) O(n) O(1) O(m+n)
Linked List (unsorted) - O(n) O(n) O(1) O(1) O(1) O(1)
Binary Heap O(n) O(1) O(log(n)) O(log(n)) O(log(n)) O(log(n)) O(m+n)
Binomial Heap - O(1) O(log(n)) O(log(n)) O(1) O(log(n)) O(log(n))
Fibonacci Heap - O(1) O(log(n)) O(1) O(1) O(log(n)) O(1)