Algorithms and Data Structures implemented in Python

Here are code snippets about algorithms, data structures, problems. These codes are written for practice and need to be optimised.

Data struct

• stack
• queue
• heap (TODO)
• priority queue
• single linked list
• double linked list (TODO)
• skip list (TODO)
• hash table
• graph
• recursive binary search tree
• iterative binary search tree (TODO)
• cartesian tree (TODO)
• b-tree (TODO)
• red-black tree (TODO)
• splay tree (TODO)
• avl tree (TODO)
• kd tree (TODO)
• trie

Algorithm

• combination
• purmutation
• recursive binary search
• iterative binary search
• depth first search
• breadth first search
• parametric search (TODO)
• quick sort
• merge sort
• tim sort (TODO)
• heap sort (TODO)
• bubble sort
• insertion sort
• selection sort
• tree sort (TODO)
• shell sort (TODO)
• bucket sort (TODO)
• radix sort (TODO)
• counting sort
• cube sort (TODO)
• topological sort (TODO)
• dijkstra (TODO)
• a* (TODO)
• run-Length encoding (TODO)
• huffman code (TODO)
• rabin karp (TODO)

Problem

• recursive factorial

• two sum (leetcode #1)

• median of two sorted arrays (leetcode #4) (TODO)

• reverse integer (leetcode #7)

• execlusive time of functions (leetcode #6)

• regular expression matching (leetcode #10) (TODO)

• roman to integer (leetcode #13)

• longest common prerix (leetcode #14)

• letter combinations of a phone number (leetcode #17)

• valid parentheses (leetcode #20)

• generate parentheses (leetcode #22)

• merge k sorted lists (leetcode #23) (TODO)

• next permutation (leetcode #31)

• search insert position (leetcode #35)

• valid sudoku (leetcode #36)

• trapping rain water (leetcode #42) (TODO)

• group anagram (leetcode #49)

• pow(x, n) (leetcode #50)

• spiral matrix (leetcode #54)

• merge intervals (leetcode #56)

• plus one (leetcode #66)

• climbing stairs (leetcode #70)

• binary tree inorder traversal - recursive (leetcode #94)

• binary tree inorder traversal - iterative (leetcode #94)

• binary tree inorder traversal - thread binary tree (leetcode #94)

• symmetric tree (leetcode #101)

• binary tree level order traversal (leetcode #102)

• binary tree zigzag level order traversal (leetcode #103)

• pascal's triangle (leetcode #118)

• longest consecutive sequence (leetcode #128)

• single number (leetcode #136)

• word break (leetcode #139)

• word break ii (leetcode #140)

• lru cache (leetcode #146) (TODO)

• reverse words in a string (leetcode #151) (TODO)

• min sack (leetcode #155)

• find peak element (leetcode #162)

• majority element (leetcode #169)

• binary search tree iterator (leetcode #173)

• number of islands (leetcode #200)

• implement trie (prefix tree) (leetcode #208)

• add and search word (leetcode #211)

• contains duplicate (leetcode #217)

• the skyline problem (leetcode #218) (TODO)

• basic calculator (leetcode #224)

• summary ranges (leetcode #228) (TODO)

• kth smallest element in bst (leetcode #230)

• power of two (leetcode #231)

• search a 2d matrix ii (leetcode #240)

• meeting rooms (leetcode #252)

• meeting rooms ii (leetcode #253) (TODO)

• single number iii (leetcode #260)

• encode and decode strings (leetcode #6)

• perfect squares (leetcode #279)

• wiggle sort (leetcode #280) (TODO)

• move zeros (leetcode #283)

• game of life (leetcode #289) (TODO)

• serialize and deserialize binary tree (leetcode #297)

• binary tree longest consecutive sequence (leetcode #298)

• burst balloons (leetcode #312) (TODO)

• count of samller numbers after self (leetcode #315) (TODO)

• remove duplicate letters (leetcode #316) (TODO)

• power of three (leetcode #326)

• palindrome pairs (leetcode #336) (TODO)

• flatten nested list iterator (leetcode #341) (TODO)

• reverse vowels of a string (leetcode #345)

• reverse string (leetcode #344)

• first unique character in a string (leetcode #387)

• longest absolute file path (leetcode #388) (TODO)

• queue reconstruction by height (leetcode #406) (TODO)

• maximum xor of two numbers in an array (leetcode #421)

• find all numbers disappeared in an array (leetcode #448) (TODO)

• delete node in a BST (leetcode #450) (TODO)

• island perimeter (leetcode #463) (TODO)

• find largest value in each tree row (leetcode #515)

• encode and decode tinyurl (leetcode #535)

• maximum depth of N-ary tree (leetcode #559) (TODO)

• n-ary tree preorder traversal (leetcode #589)

• shopping offers (leetcode #638)

• exchange rate

• robot return to origin (leetcode #657) (TODO)

• maximum swap (leetcode #670)

• next closest time (leetcode #681) (TODO)

• max area of island (leetcode #695) (TODO)

• daily temperatures (leetcode #739) (TODO)

• find anagram mappings (leetcode #760)

• letter case permutation (leetcode #784)

• split array with same average (leetcode #805)

• flipping an image (leetcode #832) (TODO)

• shortest path visiting all nodes (leetcode #847)

• middle of the linked list (leetcode #879) (TODO)

• minimum add to make parentheses valid (leetcode #921) (TODO)