LeetCode

This is my LeetCode practices.

I write solutions in Python 3. I only write free algorithm problems. (No locked, shell, database or concurrency problems)

#	Title	Solution	Topics
1	Two Sum	1-Two-Sum.md	Array, Hash Table
2	Add Two Numbers	2-Add-Two-Numbers.md	Linked List, Math
3	Longest Substring Without Repeating Characters	3-Longest-Substring-Without-Repeating-Characters.md	Hash Table, Two Pointers, String, Sliding Window
4	Median of Two Sorted Arrays	4-Median-of-Two-Sorted-Arrays.md	Array, Binary Search, Divide and Conquer
5	Longest Palindromic Substring	5-Longest-Palindromic-Substring.md	String, Dynamic Programming
6	ZigZag Conversion	6-ZigZag-Conversion.md	String
7	Reverse Integer	7-Reverse-Integer.md	Math
8	String to Integer (atoi)	8-String-to-Integer-(atoi).md	Math, String
9	Palindrome Number	9-Palindrome-Number.md	Math
10	Regular Expression Matching	10-Regular-Expression-Matching.md	String, Dynamic Programming, Backtracking
11	Container With Most Water	11-Container-With-Most-Water.md	Array, Two Pointers
12	Integer to Roman	12-Integer-to-Roman.md	Math, String
13	Roman to Integer	13-Roman-to-Integer.md	Math, String
14	Longest Common Prefix	14-Longest-Common-Prefix.md	String
15	3Sum	15-3Sum.md	Array, Two Pointers
16	3Sum Closest	16-3Sum-Closest.md	Array, Two Pointers
17	Letter Combinations of a Phone Number	17-Letter-Combinations-of-a-Phone-Number.md	String, Backtracking, Depth-first Search, Recursion
18	4Sum	18-4Sum.md	Array, Hash Table, Two Pointers
19	Remove Nth Node From End of List	19-Remove-Nth-Node-From-End-of-List.md	Linked List, Two Pointers
20	Valid Parentheses	20-Valid-Parentheses.md	String, Stack
21	Merge Two Sorted Lists	21-Merge-Two-Sorted-Lists.md	Linked List
22	Generate Parentheses	22-Generate-Parentheses.md	String, Backtracking
23	Merge k Sorted Lists	23-Merge-k-Sorted-Lists.md	Linked List, Divide and Conquer, Heap
24	Swap Nodes in Pairs	24-Swap-Nodes-in-Pairs.md	Linked List, Recursion
25	Reverse Nodes in k-Group	25-Reverse-Nodes-in-k-Group.md	Linked List
26	Remove Duplicates from Sorted Array	26-Remove-Duplicates-from-Sorted-Array.md	Array, Two Pointers
27	Remove Element	27-Remove-Element.md	Array, Two Pointers
28	Implement strStr()	28-Implement-strStr().md	Two Pointers, String
29	Divide Two Integers	29-Divide-Two-Integers.md	Math, Binary Search
30	Substring with Concatenation of All Words	30-Substring-with-Concatenation-of-All-Words.md	Hash Table, Two Pointers, String
31	Next Permutation	31-Next-Permutation.md	Array
32	Longest Valid Parentheses	32-Longest-Valid-Parentheses.md	Array, Dynamic Programming
33	Search in Rotated Sorted Array	33-Search-in-Rotated-Sorted-Array.md	Array, Binary Search
34	Find First and Last Position of Element in Sorted Array	34-Find-First-and-Last-Position-of-Element-in-Sorted-Array.md	Array, Binary Search
35	Search Insert Position	35-Search-Insert-Position.md	Array, Binary Search
36	Valid Sudoku	36-Valid-Sudoku.md	Hash Table
37	Sudoku Solver	37-Sudoku-Solver.md	Hash Table, Backtracking
38	Count and Say	38-Count-and-Say.md	String
39	Combination Sum	39-Combination-Sum.md	Array, Backtracking
40	Combination Sum II	40-Combination-Sum-II.md	Array, Backtracking
41	First Missing Positive	41-First-Missing-Positive.md	Array
42	Trapping Rain Water	42-Trapping-Rain-Water.md	Array, Two Pointer, Stack
43	Multiply Strings	43-Multiply-Strings.md	Math, String
44	Wildcard Matching	44-Wildcard-Matching.md	String, Dynamic Programming, Backtracking, Greedy
45	Jump Game II	45-Jump-Game-II.md	Array, Greedy
46	Permutations	46-Permutations.md	Backtracking
47	Permutations II	47-Permutations-II.md	Backtracking
48	Rotate Image	48-Rotate-Image.md	Array
49	Group Anagrams	49-Group-Anagrams.md	Hash Table, String
50	Pow(x, n)	50-Pow(x,n).md	Math, Binary Search
51	N-Queens	51-N-Queens.md	Backtracking
52	N-Queens II	52-N-Queens-II.md	Backtracking
53	Maximum Subarray	53-Maximum-Subarray.md	Array, Divide and Conquer, Dynamic Programming
54	Spiral Matrix	54-Spiral-Matrix.md	Array
55	Jump Game	55-Jump-Game.md	Array, Greedy
56	Merge Intervals	56-Merge-Intervals.md	Array, Sort
57	Insert Interval	57-Insert-Interval.md	Array, Sort
59	Spiral Matrix II	59-Spiral-Matrix-II.md	Array
60	Permutation Sequence	60-Permutation-Sequence.md	Math, Backtracking
61	Rotate List	61-Rotate-List.md	Linked List, Two Pointers
62	Unique Paths	62-Unique-Paths.md	Array, Dynamic Programming
63	Unique Paths II	63-Unique-Paths-II.md	Array, Dynamic Programming
64	Minimum Path Sum	64-Minimum-Path-Sum.md	Array, Dynamic Programming
65	Valid Number	65-Valid-Number.md	Math, String
66	Plus One	66-Plus-One.md	Array
67	Add Binary	67-Add-Binary.md	Math, String
68	Text Justification	68-Text-Justification.md	String
69	Sqrt(x)	69-Sqrt(x).md	Math, Binary Search
70	Climbing Stairs	70-Climbing-Stairs.md	Dynamic Programming
71	Simplify Path	71-Simplify-Path.md	String, Stack
72	Edit Distance	72-Edit-Distance.md	String, Dynamic Programming
73	Set Matrix Zeroes	73-Set-Matrix-Zeroes.md	Array
74	Search a 2D Matrix	74-Search-a-2D-Matrix.md	Array, Binary Search
76	Minimum Window Substring	76-Minimum-Window-Substring.md	Hash Table, Two Pointers, String, Sliding Window
77	Combinations	77-Combinations.md	Backtracking
78	Subsets	78-Subsets.md	Array, Backtracking, Bit Manipulation
79	Word Search	79-Word-Search.md	Array, Backtracking
80	Remove Duplicates from Sorted Array II	80-Remove-Duplicates-from-Sorted-Array-II.md	Array, Two Pointers
81	Search in Rotated Sorted Array II	81-Search-in-Rotated-Sorted-Array-II.md	Array, Binary Search
82	Remove Duplicates from Sorted List II	82-Remove-Duplicates-from-Sorted-List-II.md	Linked List
83	Remove Duplicates from Sorted List	83-Remove-Duplicates-from-Sorted-List.md	Linked List
410	Split Array Largest Sum	410-Split-Array-Largest-Sum.md	Binary Search, Dynamic Programming