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- Find Distance in a Binary Tree
- The Number of Employees Which Report to Each Employee
- Shortest Path to Get Food
- Find Followers Count
- Checking Existence of Edge Length Limited Paths II
- Count Apples and Oranges
- Sum Of Special Evenly-Spaced Elements In Array
- Biggest Window Between Visits
- Largest Subarray Length K
- Number of Calls Between Two Persons
- Number of Distinct Substrings in a String
- Daily Leads and Partners
- Count Ways to Distribute Candies
- Invalid Tweets
- Longest Palindromic Subsequence II
- Product's Worth Over Invoices
- Lowest Common Ancestor of a Binary Tree IV
- Fix Names in a Table
- Change the Root of a Binary Tree
- Average Time of Process per Machine
- Correct a Binary Tree
- Hopper Company Queries III
- Lowest Common Ancestor of a Binary Tree III
- Hopper Company Queries II
- Lowest Common Ancestor of a Binary Tree II
- Hopper Company Queries I
- Add Two Polynomials Represented as Linked Lists
- Percentage of Users Attended a Contest
- Design an Expression Tree With Evaluate Function
- All Valid Triplets That Can Represent a Country
- Maximum Font to Fit a Sentence in a Screen
- Find the Missing IDs
- Check If Two Expression Trees are Equivalent
- Sellers With No Sales
- Find Nearest Right Node in Binary Tree
- Build Binary Expression Tree From Infix Expression
- The Most Frequently Ordered Products for Each Customer
- Bank Account Summary II
- Binary Search Tree Iterator II
- Customer Who Visited but Did Not Make Any Transactions
- Put Boxes Into the Warehouse II
- Warehouse Manager
- Dot Product of Two Sparse Vectors
- Unique Orders and Customers Per Month
- Put Boxes Into the Warehouse I
- Bank Account Summary
- Strings Differ by One Character
- The Most Recent Orders for Each Product
- The Most Similar Path in a Graph
- Fix Product Name Format
- Guess the Majority in a Hidden Array
- Find the Index of the Large Integer
- The Most Recent Three Orders
- Patients With a Condition
- Diameter of N-Ary Tree
- Find Users With Valid E-Mails
- Move Sub-Tree of N-Ary Tree
- Customer Order Frequency
- Find Root of N-Ary Tree
- Countries You Can Safely Invest In
- Design a File Sharing System
- Friendly Movies Streamed Last Month
- Clone N-ary Tree
- Clone Binary Tree With Random Pointer
- Group Sold Products By The Date
- Sales by Day of the Week
- Delete N Nodes After M Nodes of a Linked List
- Find All The Lonely Nodes
- Calculate Salaries
- Rectangles Area
- Active Users
- Apples & Oranges
- Evaluate Boolean Expression
- Create a Session Bar Chart
- NPV Queries
- Find the Quiet Students in All Exams
- Top Travellers
- Customers Who Bought Products A and B but Not C
- Capital Gain/Loss
- Total Sales Amount by Year
- Replace Employee ID With The Unique Identifier
- Get the Second Most Recent Activity
- Number of Trusted Contacts of a Customer
- Activity Participants
- Students With Invalid Departments
- Movie Rating
- Number of Transactions per Visit
- List the Products Ordered in a Period
- Ads Performance
- Restaurant Growth
- Running Total for Different Genders
- Find the Team Size
- Check If a String Is a Valid Sequence from Root to Leaves Path in a Binary Tree
- Weather Type in Each Country
- Find the Start and End Number of Continuous Ranges
- Students and Examinations
- Traffic Light Controlled Intersection
- All People Report to the Given Manager
- Print Immutable Linked List in Reverse
- Page Recommendations
- Counting Elements
- Average Selling Price
- Web Crawler Multithreaded
- Number of Comments per Post
- Leftmost Column with at Least a One
- Web Crawler
- First Unique Number
- Report Contiguous Dates
- Perform String Shifts
- Team Scores in Football Tournament
- Queries Quality and Percentage
- Monthly Transactions II
- Last Person to Fit in the Elevator
- Tournament Winners
- Monthly Transactions I
- Design Bounded Blocking Queue
- Immediate Food Delivery II
- Immediate Food Delivery I
- Diet Plan Performance
- Product Price at a Given Date
- Market Analysis II
- Market Analysis I
- Article Views II
- Article Views I
- User Activity for the Past 30 Days II
- User Activity for the Past 30 Days I
- Reported Posts II
- Number of Ships in a Rectangle
- User Purchase Platform
- Active Businesses
- Reported Posts
- Highest Grade For Each Student
- Handshakes That Don't Cross
- New Users Daily Count
- Palindrome Removal
- Delete Tree Nodes
- Remove Interval
- Hexspeak
- Unpopular Books
- Game Play Analysis V
- Divide Chocolate
- Synonymous Sentences
- Smallest Common Region
- Encode Number
- Game Play Analysis IV
- Game Play Analysis III
- Game Play Analysis II
- Game Play Analysis I
- Valid Palindrome III
- Tree Diameter
- Design A Leaderboard
- Array Transformation
- Sales Analysis III
- Sales Analysis II
- Sales Analysis I
- Minimum Time to Build Blocks
- Toss Strange Coins
- Meeting Scheduler
- Missing Number In Arithmetic Progression
- Project Employees III
- Project Employees II
- Project Employees I
- Product Sales Analysis III
- Product Sales Analysis II
- Product Sales Analysis I
- Lexicographically Smallest Equivalent String
- Number of Valid Subarrays
- Longest Repeating Substring
- Missing Element in Sorted Array
- All Paths from Source Lead to Destination
- Confusing Number
- Minimize Rounding Error to Meet Target
- Campus Bikes
- Shortest Way to Form String
- Maximum Number of Ones
- Stepping Numbers
- Two Sum BSTs
- Intersection of Three Sorted Arrays
- Optimize Water Distribution in a Village
- Find Smallest Common Element in All Rows
- Minimum Knight Moves
- How Many Apples Can You Put into the Basket
- Actors and Directors Who Cooperated At Least Three Times
- Customers Who Bought All Products
- Shortest Distance to Target Color
- Before and After Puzzle
- Count Substrings with Only One Distinct Letter
- Minimum Cost to Connect Sticks
- Design File System
- String Transforms Into Another String
- Single-Row Keyboard
- Divide Array Into Increasing Sequences
- Analyze User Website Visit Pattern
- Minimum Swaps to Group All 1's Together
- Check If a Number Is Majority Element in a Sorted Array
- Parallel Courses
- Connecting Cities With Minimum Cost
- Path With Maximum Minimum Value
- Largest Unique Number
- Maximum Average Subtree
- Armstrong Number
- Remove Vowels from a String
- Number of Days in a Month
- The Earliest Moment When Everyone Become Friends
- Find K-Length Substrings With No Repeated Characters
- Two Sum Less Than K
- Sum of Digits in the Minimum Number
- Confusing Number II
- Brace Expansion
- Index Pairs of a String
- High Five
- Digit Count in Range
- Campus Bikes II
- Fixed Point
- Robot Room Cleaner
- Insert into a Sorted Circular Linked List
- Similar RGB Color
- Split BST
- Minimize Max Distance to Gas Station
- Search in a Sorted Array of Unknown Size
- Basic Calculator III
- Encode N-ary Tree to Binary Tree
- Serialize and Deserialize N-ary Tree
- Find Anagram Mappings
- Employee Free Time
- Bold Words in String
- Convert Binary Search Tree to Sorted Doubly Linked List
- Pour Water
- IP to CIDR
- Number Of Corner Rectangles
- Closest Leaf in a Binary Tree
- Sentence Similarity II
- Sentence Similarity
- Minimum Window Subsequence
- Max Stack
- Candy Crush
- Number of Distinct Islands II
- Number of Distinct Islands
- Next Closest Time
- K Empty Slots
- Path Sum IV
- Equal Tree Partition
- Remove 9
- Coin Path
- 4 Keys Keyboard
- Design Search Autocomplete System
- Maximum Average Subarray II
- Find the Derangement of An Array
- Design Log Storage System
- Design Excel Sum Formula
- Maximum Distance in Arrays
- Minimum Factorization
- Add Bold Tag in String
- Design Compressed String Iterator
- Biggest Single Number
- Students Report By Geography
- Average Salary: Departments VS Company
- Second Degree Follower
- Shortest Distance in a Line
- Shortest Distance in a Plane
- Triangle Judgement
- Tree Node
- Sales Person
- Consecutive Available Seats
- Friend Requests II: Who Has the Most Friends
- Design In-Memory File System
- Friend Requests I: Overall Acceptance Rate
- Kill Process
- Customer Placing the Largest Number of Orders
- Investments in 2016
- Find Customer Referee
- Count Student Number in Departments
- Find Cumulative Salary of an Employee
- Get Highest Answer Rate Question
- Squirrel Simulation
- Employee Bonus
- Winning Candidate
- Maximum Vacation Days
- Find Median Given Frequency of Numbers
- Managers with at Least 5 Direct Reports
- Median Employee Salary
- Longest Line of Consecutive One in Matrix
- Split Concatenated Strings
- Binary Tree Longest Consecutive Sequence II
- Split Array with Equal Sum
- Boundary of Binary Tree
- Output Contest Matches
- Construct Binary Tree from String
- Lonely Pixel II
- Lonely Pixel I
- Word Abbreviation
- Inorder Successor in BST II
- The Maze II
- The Maze III
- The Maze
- Max Consecutive Ones II
- Find Permutation
- Encode String with Shortest Length
- Convex Polygon
- Optimal Account Balancing
- Sequence Reconstruction
- Ternary Expression Parser
- Word Squares
- Valid Word Square
- Sentence Screen Fitting
- Minimum Unique Word Abbreviation
- Valid Word Abbreviation
- Design Phone Directory
- Range Addition
- Plus One Linked List
- Find Leaves of Binary Tree
- Nested List Weight Sum II
- Design Hit Counter
- Bomb Enemy
- Sort Transformed Array
- Logger Rate Limiter
- Rearrange String k Distance Apart
- Line Reflection
- Design Snake Game
- Android Unlock Patterns
- Design Tic-Tac-Toe
- Moving Average from Data Stream
- Longest Substring with At Most K Distinct Characters
- Nested List Weight Sum
- Largest BST Subtree
- Maximum Size Subarray Sum Equals k
- Number of Connected Components in an Undirected Graph
- Generalized Abbreviation
- Shortest Distance from All Buildings
- Binary Tree Vertical Order Traversal
- Sparse Matrix Multiplication
- Range Sum Query 2D - Mutable
- Number of Islands II
- Smallest Rectangle Enclosing Black Pixels
- Binary Tree Longest Consecutive Sequence
- Best Meeting Point
- Flip Game II
- Flip Game
- Word Pattern II
- Unique Word Abbreviation
- Walls and Gates
- Inorder Successor in BST
- Zigzag Iterator
- Wiggle Sort
- Find the Celebrity
- Paint Fence
- Closest Binary Search Tree Value II
- Encode and Decode Strings
- Closest Binary Search Tree Value
- Alien Dictionary
- Palindrome Permutation II
- Palindrome Permutation
- Paint House II
- Graph Valid Tree
- 3Sum Smaller
- Paint House
- Verify Preorder Sequence in Binary Search Tree
- Factor Combinations
- Meeting Rooms II
- Meeting Rooms
- Flatten 2D Vector
- Count Univalue Subtrees
- Group Shifted Strings
- Strobogrammatic Number III
- Strobogrammatic Number II
- Strobogrammatic Number
- Shortest Word Distance III
- Shortest Word Distance II
- Shortest Word Distance
- Reverse Words in a String II
- Two Sum III - Data structure design
- Missing Ranges
- One Edit Distance
- Longest Substring with At Most Two Distinct Characters
- Read N Characters Given Read4 II - Call multiple times
- Read N Characters Given Read4
- Binary Tree Upside Down

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