Table of Contents

• Arrays & Hashing
• Two Pointers
• Sliding Window
• Stack
• Binary Search
• Linked List
• Trees
• Tries
• Backtracking
• Graphs
• 1-D Dynamic Programming
• 2-D Dynamic Programming
• Intervals
• Greedy
• Math & Geometry
• Bit Manipulation

Arrays & Hashing

Status	Problem	Difficulty	Code
✅	Contains Duplicate	Easy	Code
✅	Valid Anagram	Easy	Code
✅	Two Sum	Easy	Code
✅	Group Anagrams	Medium	Code
✅	Top K Frequent Elements	Medium	Code
[ ]	Encode and Decode Strings	Medium	Code
✅	Product of Array Except Self	Medium	Code
✅	Valid Sudoku	Medium	Code
✅	Longest Consecutive Sequence	Hard	Code

Two Pointers

Status	Problem	Difficulty	Code
[ ]	Valid Palindrome	Easy	Code
[ ]	Two Sum II Input Array Is Sorted	Medium	Code
[ ]	3Sum	Medium	Code
[ ]	Container With Most Water	Medium	Code
[ ]	Trapping Rain Water	Hard	Code

Sliding Window

Status	Problem	Difficulty	Code
[ ]	Best Time to Buy And Sell Stock	Easy	Code
[ ]	Longest Substring Without Repeating Characters	Medium	Code
[ ]	Longest Repeating Character Replacement	Medium	Code
[ ]	Permutation In String	Medium	Code
[ ]	Minimum Window Substring	Hard	Code
[ ]	Sliding Window Maximum	Hard	Code

Stack

Status	Problem	Difficulty	Code
[ ]	Valid Parentheses	Easy	Code
[ ]	Min Stack	Medium	Code
[ ]	Evaluate Reverse Polish Notation	Medium	Code
[ ]	Generate Parentheses	Medium	Code
[ ]	Daily Temperatures	Medium	Code
[ ]	Car Fleet	Medium	Code
[ ]	Largest Rectangle In Histogram	Hard	Code

Binary Search

Status	Problem	Difficulty	Code
[ ]	Binary Search	Easy	Code
[ ]	Search a 2D Matrix	Medium	Code
[ ]	Koko Eating Bananas	Medium	Code
[ ]	Find Minimum In Rotated Sorted Array	Medium	Code
[ ]	Search In Rotated Sorted Array	Medium	Code
[ ]	Time Based Key Value Store	Medium	Code
[ ]	Median of Two Sorted Arrays	Hard	Code

Linked List

Status	Problem	Difficulty	Code
[ ]	Reverse Linked List	Easy	Code
[ ]	Merge Two Sorted Lists	Easy	Code
[ ]	Reorder List	Medium	Code
[ ]	Remove Nth Node From End of List	Medium	Code
[ ]	Copy List With Random Pointer	Medium	Code
[ ]	Add Two Numbers	Medium	Code
[ ]	Linked List Cycle	Medium	Code
[ ]	Find The Duplicate Number	Medium	Code
[ ]	LRU Cache	Medium	Code
[ ]	Merge K Sorted Lists	Hard	Code
[ ]	Reverse Nodes In K Group	Hard	Code

Trees

Status	Problem	Difficulty	Code
[ ]	Invert Binary Tree	Easy	Code
[ ]	Maximum Depth of Binary Tree	Easy	Code
[ ]	Diameter of Binary Tree	Easy	Code
[ ]	Balanced Binary Tree	Easy	Code
[ ]	Same Tree	Easy	Code
[ ]	Subtree of Another Tree	Easy	Code
[ ]	Lowest Common Ancestor of a Binary Search Tree	Medium	Code
[ ]	Binary Tree Level Order Traversal	Medium	Code
[ ]	Binary Tree Right Side View	Medium	Code
[ ]	Count Good Nodes In Binary Tree	Medium	Code
[ ]	Validate Binary Search Tree	Medium	Code
[ ]	Kth Smallest Element In a Bst	Medium	Code
[ ]	Construct Binary Tree From Preorder And Inorder Traversal	Medium	Code
[ ]	Binary Tree Maximum Path Sum	Hard	Code
[ ]	Serialize And Deserialize Binary Tree	Hard	Code

Tries

Status	Problem	Difficulty	Code
[ ]	Implement Trie Prefix Tree	Medium	Code
[ ]	Design Add And Search Words Data Structure	Medium	Code
[ ]	Word Search II	Hard	Code

Backtracking

Status	Problem	Difficulty	Code
[ ]	Subsets	Medium	Code
[ ]	Combination Sum	Medium	Code
[ ]	Permutations	Medium	Code
[ ]	Subsets II	Medium	Code
[ ]	Combination Sum II	Medium	Code
[ ]	Word Search	Medium	Code
[ ]	Palindrome Partitioning	Medium	Code
[ ]	Letter Combinations of a Phone Number	Medium	Code
[ ]	N Queens	Hard	Code

Graphs

Status	Problem	Difficulty	Code
[ ]	Number of Islands	Medium	Code
[ ]	Max Area of Island	Medium	Code
[ ]	Clone Graph	Medium	Code
[ ]	Walls And Gates	Medium	Code
[ ]	Rotting Oranges	Medium	Code
[ ]	Pacific Atlantic Water Flow	Medium	Code
[ ]	Surrounded Regions	Medium	Code
[ ]	Course Schedule	Medium	Code
[ ]	Course Schedule II	Medium	Code
[ ]	Graph Valid Tree	Medium	Code
[ ]	Number of Connected Components In An Undirected Graph	Medium	Code
[ ]	Redundant Connection	Medium	Code
[ ]	Word Ladder	Hard	Code

1-D Dynamic Programming

Status	Problem	Difficulty	Code
[ ]	Climbing Stairs	Easy	Code
[ ]	Min Cost Climbing Stairs	Easy	Code
[ ]	House Robber	Medium	Code
[ ]	House Robber II	Medium	Code
[ ]	Longest Palindromic Substring	Medium	Code
[ ]	Palindromic Substrings	Medium	Code
[ ]	Decode Ways	Medium	Code
[ ]	Coin Change	Medium	Code
[ ]	Maximum Product Subarray	Medium	Code
[ ]	Word Break	Medium	Code
[ ]	Longest Increasing Subsequence	Medium	Code
[ ]	Partition Equal Subset Sum	Medium	Code

2D Dynamic Programming

Status	Problem	Difficulty	Code
[ ]	Unique Paths	Medium	Code
[ ]	Longest Common Subsequence	Medium	Code
[ ]	Best Time to Buy And Sell Stock With Cooldown	Medium	Code
[ ]	Coin Change II	Medium	Code
[ ]	Target Sum	Medium	Code
[ ]	Interleaving String	Hard	Code
[ ]	Longest Increasing Path In a Matrix	Hard	Code
[ ]	Distinct Subsequences	Hard	Code
[ ]	Edit Distance	Hard	Code
[ ]	Burst Balloons	Hard	Code
[ ]	Regular Expression Matching	Hard	Code

Intervals

Status	Problem	Difficulty	Code
[ ]	Insert Interval	Medium	Code
[ ]	Merge Intervals	Medium	Code
[ ]	Non Overlapping Intervals	Medium	Code
[ ]	Meeting Rooms	Medium	Code
[ ]	Meeting Rooms II	Medium	Code
[ ]	Minimum Interval to Include Each Query	Hard	Code

Greedy

Status	Problem	Difficulty	Code
[ ]	Maximum Subarray	Easy	Code
[ ]	Jump Game	Medium	Code
[ ]	Jump Game II	Medium	Code
[ ]	Gas Station	Medium	Code
[ ]	Hand of Straights	Medium	Code
[ ]	Merge Triplets to Form Target Triplet	Medium	Code
[ ]	Partition Labels	Medium	Code
[ ]	Valid Parenthesis String	Hard	Code

Math & Geometry

Status	Problem	Difficulty	Code
[ ]	Rotate Image	Medium	Code
[ ]	Spiral Matrix	Medium	Code
[ ]	Set Matrix Zeroes	Medium	Code
[ ]	Happy Number	Medium	Code
[ ]	Plus One	Medium	Code
[ ]	Pow(x, n)	Medium	Code
[ ]	Multiply Strings	Medium	Code
[ ]	Detect Squares	Hard	Code

Bit Manipulation

Status	Problem	Difficulty	Code
[ ]	Single Number	Easy	Code
[ ]	Number of 1 Bits	Easy	Code
[ ]	Counting Bits	Easy	Code
[ ]	Reverse Bits	Easy	Code
[ ]	Missing Number	Easy	Code
[ ]	Sum of Two Integers	Easy	Code
[ ]	Reverse Integer	Medium	Code