Problems

String

	#	LeetCode Link	Difficulty	Solution	Data Structures	Patterns / Approaches	B75	CTCI	EPI	TIQ	CCH
*	0005	Longest Palindromic Substring	Medium	Python	String	DP	✔️			✔️

Linked List

	#	LeetCode Link	Difficulty	Solution	Data Structures	Patterns / Approaches	B75	CTCI	EPI	TIQ	CCH
	0002	Add Two Numbers	Medium	Python	Linked List	Math Recursion				✔️	✔️
*	0021	Merge Two Sorted Lists	Easy	Python	Linked List	Recursion	✔️
	0024	Swap Nodes in Pairs	Medium	Python	Linked List	Recursion					✔️
	0146	LRU Cache	Medium	Python	Linked List					✔️
*	0148	Sort List	Medium	Python	Linked List	Divide and Conquer				✔️

Stack

	#	LeetCode Link	Difficulty	Solution	Data Structures	Patterns / Approaches	B75	CTCI	EPI	TIQ	CCH
	0020	Valid Parentheses	Easy	Python	String Stack		✔️				✔️

Dynamic Programming

	#	LeetCode Link	Difficulty	Solution	Data Structures	Patterns / Approaches	B75	CTCI	EPI	TIQ	CCH
*	0072	Edit Distance	Hard	Python	String	DP

Two Pointers

	#	LeetCode Link	Difficulty	Solution	Data Structures	Patterns / Approaches	B75	CTCI	EPI	TIQ	CCH
	0011	Container With Most Water	Medium	Python	Array	Two Pointers Greedy	✔️
*	0015	3Sum	Medium	Python	Array	Two Pointers Sorting	✔️			✔️
	0016	3Sum Closest	Medium	Python	Array	Two Pointers Sorting				✔️
*	0019	Remove Nth Node From End of List	Medium	Python	Linked List	Two Pointers	✔️	✔️
	0026	Remove Duplicates from Sorted Array	Easy	Python	Array	Two Pointers				✔️

Sliding Window

	#	LeetCode Link	Difficulty	Solution	Data Structures	Patterns / Approaches	B75	CTCI	EPI	TIQ	CCH
*	0003	Longest Substring Without Repeating Characters	Medium	Python	String Hash Table	Sliding Window	✔️			✔️

Binary Search

	#	LeetCode Link	Difficulty	Solution	Data Structures	Patterns / Approaches	B75	CTCI	EPI	TIQ	CCH
*	0033	Search in Rotated Sorted Array	Medium	Python	Array	Binary Search	✔️			✔️
	0034	Find First and Last Position of Element in Sorted Array	Medium	Python	Array	Binary Search
*	0035	Search Insert Position	Easy	Python	Array	Binary Search					✔️

Divide and Conquer

	#	LeetCode Link	Difficulty	Solution	Data Structures	Patterns / Approaches	B75	CTCI	EPI	TIQ	CCH
*	0023	Merge k Sorted Lists	Hard	Python	Linked List	DC Merge Sort	✔️

Backtracking

	#	LeetCode Link	Difficulty	Solution	Data Structures	Patterns / Approaches	B75	CTCI	EPI	TIQ	CCH
	0017	Letter Combinations of a Phone Number	Medium	Python	String Hash Table	Backtracking				✔️
	0046	Permutations	Medium	Python	Array	Backtracking

Misc

	#	LeetCode Link	Difficulty	Solution	Data Structures	Patterns / Approaches	B75	CTCI	EPI	TIQ	CCH
	0001	Two Sum	Easy	Python	Array Hash Table		✔️				✔️
	0009	Palindrome Number	Easy	Python		Math					✔️
	0013	Roman to Integer	Easy	Python	String Hash Table	Math					✔️
	0014	Longest Common Prefix	Easy	Python	String
	0022	Generate Parentheses	Medium							✔️
	0046	Permutations	Medium							✔️
	0048	Rotate Image	Medium	Python	Array Matrix	Math	✔️	✔️
	0049	Group Anagrams	Medium	Python	Hash Table String	Sorting	✔️			✔️
*	0053	Maximum Subarray	Easy	Python	Array	DP DC	✔️				✔️
	0054	Spiral Matrix	Medium	Python	Array Matrix	Simulation	✔️				✔️
*	0055	Jump Game	Medium	Python	Array	DP Greedy	✔️			✔️	✔️
	0056	Merge Intervals	Medium	Python	Array	Sorting	✔️			✔️
	0057	Insert Interval	Medium	Python	Array		✔️				✔️
	0062	Unique Paths	Medium	Python	Array Matrix	Math DP Combinatorics	✔️			✔️	✔️
	0063	Unique Paths II	Medium	Python	Array Matrix	DP					✔️
	0070	Climbing Stairs	Easy	Python		Math DP Memorization	✔️				✔️
	0073	Set Matrix Zeroes	Medium	Python	Array Matrix		✔️	✔️		✔️
	0075	Sort Colors	Medium							✔️
	0076	Minimum Window Substring	Hard		Hash Table String	Sliding Window	✔️
	0078	Subsets	Medium							✔️
*	0079	Word Search	Medium	Python	Array Matrix	Backtracking	✔️			✔️
	0083	Remove Duplicates from Sorted List	Easy	Python	Linked List	Two Pointers
*	0086	Partition List	Medium	Python	Linked List	Two Pointers		✔️
	0091	Decode Ways	Medium	Python	String	DP	✔️
	0094	Binary Tree Inorder Traversal	Easy							✔️
	0098	Validate Binary Search Tree	Medium	Python	Binary Tree BST	DFS	✔️				✔️
	0100	Same Tree	Easy	Python	Binary Tree	DFS BFS	✔️
	0101	Symmetric Tree	Easy	Python	Binary Tree	DFS BFS
	0102	Binary Tree Level Order Traversal	Medium	Python	Binary Tree	BFS	✔️
	0103	Binary Tree Zigzag Level Order Traversal	Medium							✔️
	0104	Maximum Depth of Binary Tree	Easy	Python	Binary Tree	DFS BFS	✔️				✔️
*	0105	Construct Binary Tree from Preorder and Inorder Traversal	Medium	Python	Array Hash Table Binary Tree	DC	✔️			✔️
	0108	Convert Sorted Array to Binary Search Tree	Easy	Python	Array Binary Tree BST	DC					✔️
*	0109	Convert Sorted List to Binary Search Tree	Medium	Python	Linked List Binary Tree BST	DC					✔️
	0110	Balanced Binary Tree	Easy	Python	Binary Tree	DFS					✔️
*	0111	Minimum Depth of Binary Tree	Easy	Python	Binary Tree	DFS BFS					✔️
	0116	Populating Next Right Pointers in Each Node	Medium							✔️
	0118	Pascal's Triangle	Easy	Python	Array	DP
	0121	Best Time to Buy and Sell Stock	Easy	Python	Array	DP	✔️
	0122	Best Time to Buy and Sell Stock II	Easy	Python	Array	DP Greedy				✔️
*	0124	Binary Tree Maximum Path Sum	Hard	Python	Binary Tree	DP DFS	✔️
	0125	Valid Palindrome	Easy	Python	String	Two Pointers	✔️
*	0128	Longest Consecutive Sequence	Medium	Python	Array Hash Table	Union Find	✔️
	0133	Clone Graph	Medium	Python	Graph Hash Table	DFS BFS	✔️				✔️
	0136	Single Number	Easy	Python	Array	Bit Manipulation					✔️
	0137	Single Number II	Medium								✔️
	0138	Copy List with Random Pointer	Medium	Python	Linked List Hash Table						✔️
	0139	Word Break	Medium	Python	Hash Table String	DP Memorization	✔️
	0141	Linked List Cycle	Easy	Python	Linked List	Two Pointer	✔️
*	0143	Reorder List	Medium	Python	Linked List Stack	Two Pointer Recursion	✔️
	0144	Binary Tree Preorder Traversal	Easy	Python	Binary Tree	DFS
	0145	Binary Tree Postorder Traversal	Easy	Python	Binary Tree	DFS
	0150	Evaluate Reverse Polish Notation	Medium	Python	Array Stack	Math					✔️
*	0152	Maximum Product Subarray	Medium	Python	Array	DP	✔️				✔️
	0154	Find Minimum in Rotated Sorted Array II	Hard								✔️
	0153	Find Minimum in Rotated Sorted Array	Medium	Python	Array	Binary Search	✔️				✔️
	0155	Min Stack	Medium	Python	Stack	Design					✔️
	0160	Intersection of Two Linked Lists	Easy							✔️
	0162	Find Peak Element	Medium							✔️
	0163	Missing Ranges (Premium)	Easy							✔️
*	0189	Rotate Array	Medium	Python	Array	Math Two Pointers				✔️
	0190	Reverse Bits	Easy	Python		Bit Manipulation	✔️
	0191	Number of 1 Bits	Easy	Python		Bit Manipulation	✔️				✔️
	0198	House Robber	Medium	Python	Array	DP	✔️
	0200	Number of Islands	Medium	Python	Array Matrix	DFS BFS Union Find	✔️			✔️
	0206	Reverse Linked List	Easy	Python	Linked List	Recursion	✔️
*	0207	Course Schedule	Medium	Python	Graph	DFS BFS Topological Sort	✔️
	0208	Implement Trie (Prefix Tree)	Medium	Python	Trie Hash Table String	Design	✔️
*	0211	Design Add and Search Words Data Structure	Medium	Python	Trie String	DFS Design	✔️
	0212	Word Search II	Hard				✔️
	0213	House Robber II	Medium	Python	Array	DP	✔️
	0215	Kth Largest Element in an Array	Medium							✔️
	0217	Contains Duplicate	Easy	Python	Array Hash Table	Sorting	✔️	✔️
	0226	Invert Binary Tree	Easy	Python	Binary Tree	DFS BFS	✔️
	0230	Kth Smallest Element in a BST	Medium	Python	Binary Tree BST	DFS	✔️			✔️
	0235	Lowest Common Ancestor of a Binary Search Tree	Easy	Python	Binary Tree BST	DFS	✔️
*	0238	Product of Array Except Self	Medium	Python	Array	Prefix Sum	✔️
	0240	Search a 2D Matrix II	Medium							✔️
	0242	Valid Anagram	Easy	Python	Hash Table String	Sorting	✔️
	0252	Meeting Rooms (Premium)	Easy				✔️
	0253	Meeting Rooms II (Premium)	Medium				✔️			✔️
	0261	Graph Valid Tree (Premium)	Medium				✔️
	0268	Missing Number	Easy	Python	Array	Math Bit Manipulation	✔️
	0269	Alien Dictionary (Premium)	Hard				✔️
	0271	Encode and Decode Strings (Premium)	Medium				✔️
	0283	Move Zeroes	Easy	Python	Array	Two Pointers				✔️
	0285	Inorder Successor in BST	Medium							✔️
	0295	Find Median from Data Stream	Hard				✔️
*	0297	Serialize and Deserialize Binary Tree	Hard	Python	String Binary Tree	DFS BFS	✔️
*	0300	Longest Increasing Subsequence	Medium	Python	Array	Binary Search DP	✔️			✔️
*	0322	Coin Change	Medium	Python	Array	DP BFS	✔️			✔️
	0323	Number of Connected Components in an Undirected Graph (Premium)	Medium				✔️
	0328	Odd Even Linked List	Medium							✔️
	0334	Increasing Triplet Subsequence	Medium							✔️
	0338	Counting Bits	Easy	Python		DP Bit Manipulation	✔️
	0347	Top K Frequent Elements	Medium				✔️			✔️
*	0371	Sum of Two Integers	Medium	Python		Math Bit Manipulation	✔️
	0377	Combination Sum IV	Medium	Python	Array	DP	✔️
*	0380	Insert Delete GetRandom O(1)	Medium	Python	Array Hash Table	Design
	0417	Pacific Atlantic Water Flow	Medium	Python	Array Matrix	DFS BFS	✔️
*	0424	Longest Repeating Character Replacement	Medium	Python	String Hash Table	Sliding Window	✔️
	0435	Non-overlapping Intervals	Medium	Python	Array	DP Greedy Sorting	✔️
	0495	Teemo Attacking	Easy	Python	Array
	0567	Permutation in String	Medium	Python	String Hash Table	Two Pointers Sliding Window		✔️
	0572	Subtree of Another Tree	Medium	Python	Binary Tree	DFS Hash Function	✔️
	0647	Palindromic Substrings	Medium	Python	String	DP	✔️
	0796	Rotate String	Easy	Python	String			✔️
*	1143	Longest Common Subsequence	Medium	Python	String	DP	✔️

* Didn't solve independently, or worth reviewing.

Patterns

Abbr	Pattern
DC	Divide and Conquer
DP	Dynamic Programming

Lists

Abbr	List
B75	Blind 75 LeetCode Questions
CTCI	Cracking the Coding Interview
EPI	Elements of Programming Interviews, EPI to LC
TIQ	Top Interview Questions, Top Interview Questions
CCH	Clean Code Handbook

Solutions

• kamyu104/LeetCode-Solutions
• qiyuangong/leetcode
• haoel/leetcode