ljeng / cheat-sheet

Data structures & algorithms cheat sheet

cheat-sheet

This cheat sheet contains templates for common data structures and algorithms in Python.

Table of Contents

• Math
  • Fibonacci sequence
  • Line sweep
  • Reservoir sampling
• Search
  • Binary search
  • Knuth-Morris-Pratt
  • Rabin-Karp
  • Aho-Corasick
• Sorting
  • Counting sort
  • Radix sort
  • Quickselect
• Deque
  • Sliding window
  • String parsing
  • All nearest smaller values
• Tree
  • Depth-first traversal
  • Memoization
  • Level-order traversal
  • Binary tree recovery
• Graph
  • Dijkstra's algorithm
  • Bellman-Ford
  • Floyd-Warshall
  • Bipartite
  • Kruskal's algorithm
  • Prim's algorithm
  • Topological sort
  • Get neighbors
  • Convert adjacency matrix to graph
  • Flood fill
    • Flood fill borders
  • Word ladder
  • Floyd's tortoise and hare
  • Longest path
• Dynamic Programming
  • Kadane's algorithm
  • Best time to buy and sell stock
  • Single number
  • Wagner-Fischer
  • 2D prefix sum
    • 2D range sum
  • Hirschberg's algorithm
  • Longest common subsequence
  • Longest palindromic subsequence
  • Knapsack problem
  • Matrix chain multiplication

cheat-sheet's Issues

Algorithms that need to be implemented

String manipulation: add two numbers, reverse integer, multiply strings
K-sum
Merge k sorted lists
Reverse nodes in k-group
Regex: regular expression matching, wildcard matching

Add "nice to knows" for LCS and quickselect

It's nice to know that the LCS problem can be solved in O(n) space using the algorithm made by Hirschberg.

It's nice to know that quick-select can be done in O(n) worst-case (deterministic).

These "more efficient" implementations likely aren't as easy to understand/modify so I get that someone may intentionally choose the ones that you have here