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Meta Master DSA Sheet

This compilation contains exclusive, previously asked data structure and algorithm questions from real Meta interviews. Focus on these core problem patterns to confidently tackle even the hardest interview challenges.

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Minimum Genetic Mutation
Maximum Count of Positive Integer and Negative Integer
Asteroid Collision3 Months
Minimum Bit Flips to Convert Number
Find the Integer Added to Array II
Customer Who Visited but Did Not Make Any Transactions6 Months
Jump Game II6 Months
Rotating the Box
Majority Element II
Find the Closest Palindrome
Maximize Area of Square Hole in Grid6 Months
Walking Robot Simulation
Maximum Alternating Subsequence Sum
Longest Univalue Path
Valid Parentheses30 Days
Min Stack3 Months
Find Followers Count
Fruits Into Baskets II6 Months
Longest Subarray of 1's After Deleting One Element
Invalid Tweets
Vowel Spellchecker
Find Resultant Array After Removing Anagrams
Bitwise XOR of All Pairings
User Activity for the Past 30 Days II
Special Array I
Find Closest Number to Zero
K Inverse Pairs Array
Smallest Range Covering Elements from K Lists
Second Highest Salary6 Months
Grumpy Bookstore Owner6 Months
Monthly Transactions I
Convert Sorted List to Binary Search Tree
Delete Characters to Make Fancy String
Tree Node3 Months
Inorder Successor in BST
Avoid Flood in The City
Shortest Cycle in a Graph
Minimum ASCII Delete Sum for Two Strings3 Months
Kth Smallest Element in a Sorted Matrix30 Days
Open the Lock6 Months
Snapshot Array
Validate IP Address6 Months
Find the Length of the Longest Common Prefix
Design HashMap3 Months
Permutation Sequence
Meeting Rooms II30 Days
Shortest Subarray With OR at Least K II
Number of Connected Components in an Undirected Graph
Destination City
Longest Nice Subarray
Best Meeting Point
Max Stack
User Activity for the Past 30 Days I6 Months
Count Unguarded Cells in the Grid6 Months
Minimum Moves to Reach Target Score
Using a Robot to Print the Lexicographically Smallest String
Special Array II
Furthest Building You Can Reach
Best Sightseeing Pair
Print Binary Tree
Reverse Linked List3 Months
Design Tic-Tac-Toe6 Months
Max Difference You Can Get From Changing an Integer
Sort Matrix by Diagonals
Find a Peak Element II
Course Schedule II30 Days
Minimum Height Trees
Dota2 Senate
Subarray Product Less Than K3 Months
Word Ladder II6 Months
N-Queens II
Knight Probability in Chessboard
Insert Delete GetRandom O(1) - Duplicates allowed
Minimum Penalty for a Shop
Unique Binary Search Trees3 Months
Zigzag Conversion3 Months
Shortest Distance from All Buildings6 Months
Minimum Deletions to Make String Balanced30 Days
Brick Wall
Investments in 2016
Count the Number of Infection Sequences6 Months
Count Equal and Divisible Pairs in an Array
Pacific Atlantic Water Flow6 Months
Letter Case Permutation6 Months
Find Common Characters
Top K Frequent Words6 Months
Alternating Groups I
Linked List in Binary Tree
Spiral Matrix3 Months
Graph Valid Tree
Count the Number of Arrays with K Matching Adjacent Elements
Design Skiplist
Nth Highest Salary
Partition Array Into Two Arrays to Minimize Sum Difference
Longest Harmonious Subsequence
Power of Four
Find K Closest Elements6 Months
Movie Rating3 Months
Remove Sub-Folders from the Filesystem
Alien Dictionary3 Months
Count Subarrays With Score Less Than K
All Nodes Distance K in Binary Tree30 Days
Copy List with Random Pointer3 Months
Count the Number of Powerful Integers
Merge Intervals30 Days
Minimum Distance Between BST Nodes
Group Shifted Strings3 Months
Clone Graph3 Months
Maximum Height by Stacking Cuboids6 Months
Time Based Key-Value Store6 Months
Find Original Array From Doubled Array
Minimum Cost For Tickets6 Months
Baseball Game
Longest Palindromic Substring30 Days
Substring with Concatenation of All Words6 Months
Generate Parentheses30 Days
Two City Scheduling
Search Suggestions System
Find Numbers with Even Number of Digits6 Months
Minimum Number of Days to Make m Bouquets
Next Permutation3 Months
Split Array Largest Sum6 Months
Serialize and Deserialize Binary Tree6 Months
Longest String Chain
Pow(x, n)3 Months
K Closest Points to Origin30 Days
Peeking Iterator
Battleships in a Board30 Days
Longest Substring Without Repeating Characters3 Months
Painting the Walls
Maximum Product of Two Elements in an Array
Diameter of Binary Tree30 Days
Count the Hidden Sequences
Product of Array Except Self30 Days
Minimum Cost of Buying Candies With Discount
Koko Eating Bananas3 Months
Subtract the Product and Sum of Digits of an Integer
Maximum Product Subarray3 Months
Block Placement Queries
Next Greater Numerically Balanced Number6 Months
Design HashSet
Encode and Decode Strings
Finding Pairs With a Certain Sum6 Months
Number of Days Between Two Dates
Maximum Sum Circular Subarray
Capital Gain/Loss
Divide Intervals Into Minimum Number of Groups
3Sum With Multiplicity
Climbing Stairs3 Months
Transpose Matrix6 Months
The Number of Employees Which Report to Each Employee
Verifying an Alien Dictionary
Distribute Candies Among Children II
Managers with at Least 5 Direct Reports
Two Sum IV - Input is a BST
Car Pooling6 Months
Binary Tree Paths6 Months
Kth Smallest Element in a BST6 Months
Trapping Rain Water30 Days
Event Emitter
Path Sum III
Palindrome Pairs
Maximum Depth of Binary Tree6 Months
Minimum Knight Moves6 Months
Minimum Window Substring30 Days
Minimum Difference Between Highest and Lowest of K Scores
Swim in Rising Water30 Days
Max Chunks To Make Sorted
Task Scheduler
Analyze User Website Visit Pattern
Shortest Way to Form String
Decoded String at Index
Basic Calculator II3 Months
Average Time of Process per Machine6 Months
Basic Calculator III
My Calendar I
Rabbits in Forest6 Months
Rotate Image3 Months
Find Winner on a Tic Tac Toe Game
Exchange Seats
Find All Numbers Disappeared in an Array3 Months
Number of Visible People in a Queue
Middle of the Linked List3 Months
Valid Sudoku6 Months
Count Sub Islands
Longest Repeating Character Replacement3 Months
Maximum Profit in Job Scheduling
Minimum Number of K Consecutive Bit Flips
House Robber III
Number of 1 Bits6 Months
Permutation in String6 Months
Find All Anagrams in a String3 Months
Reverse Bits6 Months
Merge Two Binary Trees6 Months
Palindrome Partitioning II
Capacity To Ship Packages Within D Days6 Months
Random Pick with Weight30 Days
Sqrt(x)3 Months
Find the Prefix Common Array of Two Arrays
Group the People Given the Group Size They Belong To
Valid Palindrome II30 Days
Queue Reconstruction by Height
Maximum Number of Tasks You Can Assign
Wildcard Matching
Find Words That Can Be Formed by Characters
Divisor Game
Minimum Area Rectangle
IPO
Two Furthest Houses With Different Colors
Stock Price Fluctuation
First Unique Number
Maximum Sum BST in Binary Tree
One Edit Distance
Largest Number
Regular Expression Matching6 Months
Count Ways To Build Good Strings
Unique Paths II
Calculate Amount Paid in Taxes
Game of Life6 Months
Maximum Width Ramp
Reverse Nodes in Even Length Groups
Number of Ways to Form a Target String Given a Dictionary
Longest Increasing Path in a Matrix3 Months
Daily Temperatures3 Months
Remove Boxes
Students and Examinations6 Months
Longest Strictly Increasing or Strictly Decreasing Subarray
Convert Binary Number in a Linked List to Integer
First Missing Positive30 Days
Remove All Occurrences of a Substring6 Months
Maximum Swap3 Months
Count Elements With Maximum Frequency6 Months
Valid Word
Making A Large Island3 Months
Longest Common Subsequence6 Months
Populating Next Right Pointers in Each Node II3 Months
Add Binary30 Days
Web Crawler Multithreaded
Binary Tree Cameras
Bitwise ORs of Subarrays
Power Grid Maintenance6 Months
All O`one Data Structure
Two Sum II - Input Array Is Sorted6 Months
Number of Islands30 Days
Web Crawler
Walls and Gates6 Months
Word Search II6 Months
Burst Balloons
Range Sum Query 2D - Immutable
Closest Prime Numbers in Range
LRU Cache3 Months
Maximal Square
String Compression30 Days
Design Snake Game
Interval List Intersections3 Months
Trapping Rain Water II6 Months
Isomorphic Strings30 Days
Find All Possible Recipes from Given Supplies
Count Binary Substrings3 Months
Partition to K Equal Sum Subsets
Permutations30 Days
Partition Array Into Three Parts With Equal Sum
Linked List Cycle II
Merge Sorted Array30 Days
Restaurant Growth
Pascal's Triangle3 Months
Maximum Total Damage With Spell Casting
Single Number III
Count and Say
Sliding Window Median3 Months
Matrix Similarity After Cyclic Shifts
Find and Replace Pattern
Longest Common Prefix30 Days
Design In-Memory File System
Valid Perfect Square
Minimum Cost Path with Edge Reversals
Logger Rate Limiter
Insert Interval30 Days
Detect Cycles in 2D Grid
Check if a Parentheses String Can Be Valid
Maximum Sum of Distinct Subarrays With Length K
Valid Number3 Months
Find the Smallest Divisor Given a Threshold
Beautiful Towers I
Longest Arithmetic Subsequence
Shortest Bridge6 Months
Largest Plus Sign
Palindromic Substrings30 Days
Exclusive Time of Functions30 Days
Max Sum of a Pair With Equal Sum of Digits
Successful Pairs of Spells and Potions6 Months
Minimum Number of Refueling Stops
Find the Index of the First Occurrence in a String6 Months
Snakes and Ladders
Last Person to Fit in the Bus
Heaters
Product of the Last K Numbers6 Months
Leftmost Column with at Least a One
Angle Between Hands of a Clock
Maximum Earnings From Taxi
Non-overlapping Intervals6 Months
Basic Calculator3 Months
Single Element in a Sorted Array3 Months
LFU Cache
Rotting Oranges3 Months
Satisfiability of Equality Equations
Two Sum30 Days
Move Zeroes30 Days
Guess the Word3 Months
Height Checker
Combination Sum3 Months
Roman to Integer3 Months
Search in Rotated Sorted Array3 Months
Longest Valid Parentheses3 Months
Design Circular Queue
Backspace String Compare
Collect Coins in a Tree
Remove K Digits6 Months
Bus Routes
Set Matrix Zeroes3 Months
Restore IP Addresses
Shortest Path in Binary Matrix3 Months
Find Minimum Time to Reach Last Room I
Container With Most Water3 Months
Fair Candy Swap3 Months
Toeplitz Matrix3 Months
Insert Delete GetRandom O(1)6 Months
Lemonade Change
Max Points on a Line
Course Schedule3 Months
Search a 2D Matrix II
Rectangle Overlap
Minimize the Maximum Difference of Pairs
Divide Nodes Into the Maximum Number of Groups
Split a String in Balanced Strings3 Months
Shifting Letters II
Cherry Pickup
The Skyline Problem6 Months
Maximum Subarray3 Months
Design Parking System
Count Subarrays With Fixed Bounds
Fraction Addition and Subtraction
Path With Minimum Effort6 Months
Department Highest Salary
Average Waiting Time
Squares of a Sorted Array6 Months
Word Ladder6 Months
Count Square Submatrices with All Ones
Contains Duplicate3 Months
Edit Distance
Count Complete Subarrays in an Array
Kth Largest Element in a Stream6 Months
Decode String6 Months
Minimum Absolute Difference Between Elements With Constraint6 Months
Bulls and Cows
Reverse Words in a String30 Days
Intersection of Two Linked Lists3 Months
Split Message Based on Limit
Loud and Rich
Shuffle an Array
Minimum Time to Collect All Apples in a Tree6 Months
Implement Stack using Queues6 Months
Average Selling Price6 Months
Merge k Sorted Lists30 Days
Reorder List6 Months
Find the Duplicate Number3 Months
Greatest Common Divisor of Strings6 Months
Encode and Decode TinyURL
Find Users With Valid E-Mails
Decode Ways II
Sum of Nodes with Even-Valued Grandparent
Convert Binary Search Tree to Sorted Doubly Linked List30 Days
Remove Max Number of Edges to Keep Graph Fully Traversable
Grid Teleportation Traversal
Final Prices With a Special Discount in a Shop
Integer to Roman3 Months
Replace Elements with Greatest Element on Right Side
Contiguous Array3 Months
Remove Invalid Parentheses3 Months
Partition Equal Subset Sum3 Months
Best Time to Buy and Sell Stock II6 Months
Score of Parentheses
Construct Binary Tree from Inorder and Postorder Traversal
Divide Array Into Arrays With Max Difference
Find Duplicate Subtrees
Implement Trie (Prefix Tree)
Word Break II
Course Schedule IV
Rotate Array6 Months
Make Sum Divisible by P
Zigzag Grid Traversal With Skip
Sum of Subarray Minimums
Construct Binary Tree from String6 Months
Online Stock Span
The Maze II6 Months
Binary Tree Right Side View3 Months
Find All Duplicates in an Array
Combine Two Tables6 Months
Diagonal Traverse II6 Months
Make The String Great
Palindrome Permutation
Monotonic Array6 Months
Missing Ranges6 Months
Number of Recent Calls3 Months
The Maze
Pairs of Songs With Total Durations Divisible by 60
Minimum Cost Path with Teleportations3 Months
Concatenation of Array30 Days
Top K Frequent Elements30 Days
Merge Two Sorted Lists30 Days
Image Smoother
HTML Entity Parser
Reconstruct Itinerary
Minimum Time to Complete Trips
Race Car
Flatten Deeply Nested Array
Leaf-Similar Trees
Median of Two Sorted Arrays30 Days
Multiply Strings
Count Square Sum Triples6 Months
Linked List Random Node
Intersection of Multiple Arrays
Palindrome Number30 Days
Diagonal Traverse3 Months
Largest Rectangle in Histogram6 Months
Permutations II
Add Two Numbers3 Months
Rectangle Area
Parallel Courses
Sum of Square Numbers
Longest Substring with At Most K Distinct Characters
Find Duplicate File in System6 Months
Subsets II6 Months
Remove All Adjacent Duplicates in String II6 Months
Number of Digit One
Number of Matching Subsequences
Dungeon Game6 Months
Subarrays with K Different Integers
Island Perimeter
Flood Fill3 Months
Moving Average from Data Stream30 Days
Regions Cut By Slashes
Minimum Remove to Make Valid Parentheses30 Days
Immediate Food Delivery II
Construct K Palindrome Strings
Palindrome Partitioning3 Months
Check If Array Pairs Are Divisible by k
Triangle6 Months
Find Minimum Time to Finish All Jobs
Subarray Sum Equals K30 Days
Minimum Score Triangulation of Polygon6 Months
Reverse Nodes in k-Group6 Months
Recyclable and Low Fat Products3 Months
Remove Zero Sum Consecutive Nodes from Linked List
Sum of Two Integers
N-Queens3 Months
Maximum Number of Occurrences of a Substring
Decode the Message
Delete Node in a BST6 Months
Number of Students Unable to Eat Lunch
Longest Substring with At Most Two Distinct Characters
Shortest Palindrome
Maximum Units on a Truck
Minimum Operations to Reduce X to Zero
Validate Stack Sequences3 Months
Word Search3 Months
Maximal Rectangle3 Months
Symmetric Tree6 Months
All Ancestors of a Node in a Directed Acyclic Graph
Evaluate Division
Consecutive Numbers
Decode Ways3 Months
Design Hit Counter3 Months
Fibonacci Number3 Months
UTF-8 Validation
Same Tree30 Days
Gas Station6 Months
Trips and Users
Binary Tree Maximum Path Sum6 Months
Delete Nodes And Return Forest
Valid Anagram3 Months
Minimum Operations to Exceed Threshold Value II
Valid Palindrome30 Days
Minimum Operations to Make Binary Array Elements Equal to One I
Find the Town Judge
Letter Combinations of a Phone Number30 Days
Largest Local Values in a Matrix
Majority Element3 Months
Minimum Absolute Difference3 Months
3Sum30 Days
Lowest Common Ancestor of a Binary Tree30 Days
All Paths From Source to Target
3Sum Closest6 Months
Best Time to Buy and Sell Stock30 Days
Design Add and Search Words Data Structure
Minimum Path Sum
Reverse String3 Months
Simplify Path30 Days
Shortest Common Supersequence
Remove Linked List Elements
Candy Crush
Jump Game30 Days
Maximum Score From Removing Substrings
Find the Number of Ways to Place People II
Sort Colors6 Months
Group Anagrams3 Months
Shortest Path with Alternating Colors
Max Consecutive Ones III30 Days
Network Delay Time
Find the City With the Smallest Number of Neighbors at a Threshold Distance
Add to Array-Form of Integer
Odd Even Linked List6 Months
Sum of Unique Elements
Interleaving String
Missing Number6 Months
Implement Queue using Stacks
Continuous Subarray Sum3 Months
Maximum Product of Three Numbers
Tallest Billboard
Longest Increasing Subsequence3 Months
Number of Islands II
Binary Tree Zigzag Level Order Traversal
Validate Binary Search Tree6 Months
Add Digits3 Months
Remove Duplicates from Sorted Array3 Months
How Many Numbers Are Smaller Than the Current Number
Most Profitable Path in a Tree
Car Fleet6 Months
Delete and Earn
Remove Nth Node From End of List3 Months
Count Nodes Equal to Average of Subtree6 Months
Arranging Coins6 Months
Find Peak Element30 Days
Count the Number of Good Subarrays
Relative Sort Array
Fraction to Recurring Decimal6 Months
Number of Ways to Split Array
Intersection of Two Arrays3 Months
Best Time to Buy and Sell Stock using Strategy6 Months
Convert a Number to Hexadecimal6 Months
Missing Element in Sorted Array6 Months
Fruit Into Baskets
House Robber II6 Months
Patching Array6 Months
Reverse Only Letters
Minimum Number of Removals to Make Mountain Array
Sort Array by Increasing Frequency
Is Subsequence6 Months
N-Repeated Element in Size 2N Array
Maximum Population Year
Best Time to Buy and Sell Stock with Transaction Fee
Count Number of Nice Subarrays
Unique Paths III6 Months
Path Sum II6 Months
Number of Provinces3 Months
Reverse Vowels of a String3 Months
Remove Element6 Months
Expression Add Operators3 Months
Kth Largest Element in an Array30 Days
Cutting Ribbons
3Sum Smaller
Find Customer Referee
Find First and Last Position of Element in Sorted Array30 Days
Minimum Falling Path Sum
Count Good Numbers6 Months
Count Pairs Whose Sum is Less than Target
Prefix and Suffix Search
Debounce
Coin Change30 Days
Word Subsets
Ugly Number II
Count Nice Pairs in an Array
Nearest Exit from Entrance in Maze
Next Greater Element III
Maximum Number of Events That Can Be Attended
Paint Fence
Stickers to Spell Word
Product Sales Analysis I
Count Servers that Communicate
01 Matrix3 Months
Word Pattern6 Months
Add Bold Tag in String
Max Area of Island3 Months
Function Composition
Cheapest Flights Within K Stops
Reverse Pairs6 Months
Next Greater Element II
Decrypt String from Alphabet to Integer Mapping
Diameter of N-Ary Tree
Distinct Subsequences
Sliding Puzzle
Single Number II3 Months
Flip String to Monotone Increasing
Rotate String6 Months
Search Insert Position3 Months
Add Two Numbers II6 Months
Minimum Insertion Steps to Make a String Palindrome
Shuffle the Array
Reverse Linked List II30 Days
Sum of Digits of String After Convert
Number of Submatrices That Sum to Target
Best Time to Buy and Sell Stock III30 Days
Count Odd Numbers in an Interval Range
Is Graph Bipartite?
Number of Distinct Islands
Lowest Common Ancestor of Deepest Leaves6 Months
Fizz Buzz3 Months
Populating Next Right Pointers in Each Node3 Months
Minimum Fuel Cost to Report to the Capital
Find Score of an Array After Marking All Elements
Shortest Unsorted Continuous Subarray
Binary Tree Longest Consecutive Sequence6 Months
Cinema Seat Allocation
Delete Node in a Linked List3 Months
Flatten Binary Tree to Linked List
Plus One3 Months
Create a DataFrame from List
Sort List6 Months
Number of Closed Islands
First Unique Character in a String6 Months
Project Employees I
4Sum3 Months
Rotated Digits
Remove Duplicate Letters
Min Cost to Connect All Points
Can Place Flowers6 Months
Shortest Path in a Hidden Grid
Duplicate Emails3 Months
Range Sum of BST3 Months
132 Pattern
Reverse Words in a String III
Long Pressed Name
Search in Rotated Sorted Array II
Intersection of Two Arrays II6 Months
Excel Sheet Column Title
Spiral Matrix II6 Months
Power of Two3 Months
Dot Product of Two Sparse Vectors30 Days
Reverse Integer30 Days
Meeting Rooms III6 Months
Tree Diameter
Find the Winner of the Circular Game
Check If Two String Arrays are Equivalent
Substrings of Size Three with Distinct Characters
Champagne Tower
Integer to English Words
Longest Duplicate Substring
Water Bottles6 Months
Time Needed to Buy Tickets
Word Break3 Months
Merge Strings Alternately3 Months
Minimum Size Subarray Sum
Minimum Time Difference
Smallest Subtree with all the Deepest Nodes3 Months
Sudoku Solver6 Months
Find Minimum in Rotated Sorted Array6 Months
Longest Consecutive Sequence3 Months
Remove All Adjacent Duplicates In String3 Months
Path with Maximum Gold
Happy Number6 Months
Divide Two Integers6 Months
Maximum Points You Can Obtain from Cards6 Months
Minimum Number of Swaps to Make the String Balanced
Number of Longest Increasing Subsequence
Boundary of Binary Tree3 Months
House Robber6 Months
Find Missing and Repeated Values
Design File System
Find the Highest Altitude
Contains Duplicate II30 Days
Sum Root to Leaf Numbers30 Days
Vertical Order Traversal of a Binary Tree30 Days
Restore the Array From Adjacent Pairs3 Months
Next Greater Element I30 Days
Find K Pairs with Smallest Sums
Sliding Window Maximum3 Months
Subsets3 Months
Length of Last Word3 Months
Design Linked List
Reorganize String
Combinations30 Days
Check if Array Is Sorted and Rotated30 Days
Lowest Common Ancestor of a Binary Search Tree6 Months
Non-decreasing Array
String to Integer (atoi)3 Months
Last Stone Weight
Sum of Beauty of All Substrings6 Months
K-diff Pairs in an Array
Department Top Three Salaries
Defanging an IP Address
Minimum Cost to Make at Least One Valid Path in a Grid
Maximum Product of Splitted Binary Tree3 Months
Find the Longest Substring Containing Vowels in Even Counts
Valid Word Abbreviation30 Days
Coin Change II3 Months
Unique Paths3 Months
Number of Substrings Containing All Three Characters
Combination Sum II3 Months
N-th Tribonacci Number3 Months
Target Sum6 Months
Find Center of Star Graph
Design Memory Allocator
Insert into a Binary Search Tree
Max Consecutive Ones3 Months
Sort an Array
Valid Arrangement of Pairs
Jewels and Stones
Rising Temperature6 Months
Assign Cookies
Delete the Middle Node of a Linked List
Step-By-Step Directions From a Binary Tree Node to Another
Find Missing Observations
Remove Digit From Number to Maximize Result
Product of Two Run-Length Encoded Arrays3 Months
Palindrome Linked List3 Months
Summary Ranges
Sentence Similarity III
Length of Longest Subarray With at Most K Frequency
Strong Password Checker
Candy3 Months
Number of Good Pairs
The k-th Lexicographical String of All Happy Strings of Length n
Balanced Binary Tree30 Days
Article Views I6 Months
Text Justification6 Months
Cousins in Binary Tree
Find Lucky Integer in an Array6 Months
Add Two Integers
Reorder Routes to Make All Paths Lead to the City Zero
Longest Mountain in Array
Ugly Number
Convert Sorted Array to Binary Search Tree6 Months
Delete Duplicate Emails6 Months
Find N Unique Integers Sum up to Zero
Keys and Rooms
Find Bottom Left Tree Value
Random Pick Index6 Months
Find Median from Data Stream6 Months
Divide Array Into Equal Pairs
Count Good Nodes in Binary Tree
Employee Bonus3 Months
Best Time to Buy and Sell Stock IV
Sort Characters By Frequency6 Months
Height of Binary Tree After Subtree Removal Queries
Longest Palindromic Subsequence
Longest Continuous Increasing Subsequence
Add Strings3 Months
Scramble String
Game Play Analysis IV6 Months
Sum of Left Leaves
Construct Binary Search Tree from Preorder Traversal
Friend Requests I: Overall Acceptance Rate
Flipping an Image3 Months
Find in Mountain Array
Most Stones Removed with Same Row or Column
Parsing A Boolean Expression
Reported Posts
Project Employees II
Find the Kth Smallest Sum of a Matrix With Sorted Rows
Put Marbles in Bags
Repeated Substring Pattern
Meeting Rooms
Maximum Matrix Sum3 Months
Integer Break6 Months
Wiggle Sort II
Binary Tree Level Order Traversal3 Months
Kth Smallest Number in Multiplication Table
Maximum Binary Tree II
Find the Most Common Response
Apples & Oranges
Remove Duplicates from Sorted List3 Months
Percentage of Users Attended a Contest6 Months
Maximum Binary Tree6 Months
Max Number of K-Sum Pairs
Number Of Corner Rectangles
Min Cost Climbing Stairs6 Months
Shifting Letters
Find Common Elements Between Two Arrays
Continuous Subarrays
Nth Digit
Unique Number of Occurrences3 Months
Replace Employee ID With The Unique Identifier
Closest Binary Search Tree Value3 Months
Primary Department for Each Employee
Maximum Gap6 Months
Invert Binary Tree
Minimum Deletions for At Most K Distinct Characters
Combination Sum IV
Create Hello World Function6 Months
Faulty Sensor
Number of Comments per Post
Product Price at a Given Date6 Months
Count of Smaller Numbers After Self
Russian Doll Envelopes
Kids With the Greatest Number of Candies6 Months
Bitwise OR of Even Numbers in an Array
Count the Number of Fair Pairs
Ads Performance
Possible Bipartition
Reported Posts II
Moving Stones Until Consecutive
Customers Who Never Order
Boats to Save People6 Months
Accounts Merge6 Months
Find if Path Exists in Graph
Valid Triangle Number6 Months
Project Employees III
Maximum Compatibility Score Sum
Employees Earning More Than Their Managers30 Days
The kth Factor of n
Count Primes6 Months
Kth Missing Positive Number6 Months
Remove Duplicates from Sorted List II
Design Search Autocomplete System
Maximum Candies Allocated to K Children6 Months
Longest Balanced Substring II3 Months
Smallest Integer Divisible by K6 Months
Bulb Switcher6 Months
Find Pivot Index6 Months
Find the Original Typed String I
Counting Bits6 Months
Subarray Sums Divisible by K
Simple Bank System30 Days
Number of Operations to Make Network Connected
Split Linked List in Parts
Subtree of Another Tree
Largest Divisible Subset3 Months
Search in a Binary Search Tree
Surrounded Regions6 Months
Return Length of Arguments Passed
Remove Outermost Parentheses
Peak Index in a Mountain Array6 Months
Swap Nodes in Pairs3 Months
Find the Difference
Max Pair Sum in an Array
Longest Subsequence Repeated k Times
2 Keys Keyboard
Design an Ordered Stream
Maximum Number of Darts Inside of a Circular Dartboard
Minimum Path Cost in a Hidden Grid
Customers Who Bought Products A and B but Not C
Read N Characters Given read4 II - Call Multiple Times
Repeated DNA Sequences6 Months
Count the Number of Substrings With Dominant Ones
Maximum Average Subarray I3 Months
Repeated String Match
Shortest Subarray with Sum at Least K
Custom Sort String3 Months
Meeting Scheduler
Strong Friendship3 Months
Moving Stones Until Consecutive II
Page Recommendations II
24 Game
Maximum Nesting Depth of the Parentheses6 Months
Partition List
Find the Lexicographically Largest String From the Box I
Complete Binary Tree Inserter
Maximum Performance of a Team
Report Contiguous Dates
Get Highest Answer Rate Question
House Robber IV
Factorial Trailing Zeroes
Construct String With Repeat Limit
Count Nodes Equal to Sum of Descendants
Design Ride Sharing System
Steps to Make Array Non-decreasing
Minimum Cost to Reach Destination in Time
Identify the Largest Outlier in an Array
Merge Two 2D Arrays by Summing Values
Smallest Missing Integer Greater Than Sequential Prefix Sum
Perfect Number
Finding the Topic of Each Post
Lexicographical Numbers
Guess Number Higher or Lower
Classes With at Least 5 Students
Sign of the Product of an Array
Unique Length-3 Palindromic Subsequences
Minimum Number of Changes to Make Binary String Beautiful
Largest BST Subtree6 Months
Friend Requests II: Who Has the Most Friends6 Months
Find Words Containing Character
Max Dot Product of Two Subsequences3 Months
Page Recommendations
Binary Tree Inorder Traversal6 Months
Maximum Difference Between Even and Odd Frequency II
Contains Duplicate III
Spiral Matrix III
Find the Maximum Length of Valid Subsequence II
Recover Binary Search Tree
Two Best Non-Overlapping Events3 Months
Minimum Pair Removal to Sort Array I30 Days
Swapping Nodes in a Linked List6 Months
Valid Mountain Array3 Months
Binary Tree Vertical Order Traversal30 Days
Not Boring Movies3 Months
Binary Search Tree Iterator3 Months
Minimum Number of Operations to Move All Balls to Each Box
Element Appearing More Than 25% In Sorted Array
Valid Palindrome III3 Months
Number of Valid Words in a Sentence
Magnetic Force Between Two Balls
Maximum Frequency Stack
Minimum Add to Make Parentheses Valid3 Months
Strobogrammatic Number6 Months
Sum of Subarray Ranges
Minesweeper3 Months
Letter Tile Possibilities
Human Traffic of Stadium6 Months
Frequency of the Most Frequent Element6 Months
Search a 2D Matrix3 Months
Count Complete Tree Nodes
Employee Free Time
Nim Game
Paint House II
Linked List Cycle6 Months
Minimum Difference in Sums After Removal of Elements
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Linked List Components
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Longest Palindrome
Super Pow
Find the Difference of Two Arrays
Cherry Pickup II6 Months
Confirmation Rate3 Months
Evaluate Reverse Polish Notation3 Months
Shortest Subarray to be Removed to Make Array Sorted
Ones and Zeroes
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Find the Minimum and Maximum Number of Nodes Between Critical Points
Redundant Connection
Ransom Note6 Months
Remove Duplicates from Sorted Array II
Find Eventual Safe States
Path Sum
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Binary Subarrays With Sum3 Months
Binary Search3 Months
Nested List Weight Sum30 Days
First Bad Version30 Days
Maximum Number of Points From Grid Queries
Threshold Majority Queries
Lowest Common Ancestor of a Binary Tree II
Reordered Power of 2
Intersection of Three Sorted Arrays
Maximum Manhattan Distance After K Changes
Construct String from Binary Tree
Maximum Difference Between Even and Odd Frequency I
Minimum Number of Increments on Subarrays to Form a Target Array
Can I Win
Count Negative Numbers in a Sorted Matrix6 Months
Range Sum Query - Immutable3 Months
Partition Labels6 Months
Minimum Cost to Cut a Stick
Valid Parenthesis String3 Months
Path with Maximum Probability
Insert into a Sorted Circular Linked List6 Months
Big Countries6 Months
Binary Tree Preorder Traversal
Count Hills and Valleys in an Array
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Flatten Nested List Iterator6 Months
Find a Corresponding Node of a Binary Tree in a Clone of That Tree6 Months
Strobogrammatic Number II6 Months
To Be Or Not To Be
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Minimum Insertions to Balance a Parentheses String
Sparse Matrix Multiplication3 Months
Find the Celebrity
Rotate List6 Months
Groups of Special-Equivalent Strings
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Maximum Unique Subarray Sum After Deletion
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Most Profit Assigning Work
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Design Twitter
Shortest Path in a Grid with Obstacles Elimination6 Months
Binary Search Tree Iterator II
Set Mismatch6 Months
Calculate Money in Leetcode Bank
Richest Customer Wealth
Maximum Average Pass Ratio
H-Index
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Rearranging Fruits
Counter
Single-Threaded CPU
Single Number3 Months
Longest Substring with At Least K Repeating Characters
Stone Game II
Balance a Binary Search Tree30 Days
Game Play Analysis I
Design a Text Editor6 Months
Count of Range Sum3 Months
Words Within Two Edits of Dictionary
Pascal's Triangle II
Task Scheduler II
Strange Printer
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H-Index II
Score of a String
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Construct Binary Tree from Preorder and Inorder Traversal3 Months
Rank Scores6 Months
Buildings With an Ocean View3 Months
Third Maximum Number6 Months
Binary Tree Level Order Traversal II
Hand of Straights
Matchsticks to Square
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Max Consecutive Ones II
Robot Room Cleaner3 Months
Three Consecutive Odds6 Months
Find the XOR of Numbers Which Appear Twice6 Months
Minimum Falling Path Sum II
Find the Maximum Length of Valid Subsequence I
Set Intersection Size At Least Two6 Months
Push Dominoes
Construct the Lexicographically Largest Valid Sequence
Sum of Root To Leaf Binary Numbers
Count Symmetric Integers6 Months
Minimum Addition to Make Integer Beautiful
Maximum Difference by Remapping a Digit
Nth Magical Number6 Months
Valid Phone Numbers
Reach a Number
Minimum Absolute Difference in BST
Array Prototype Last6 Months
Fix Names in a Table
Compute Decimal Representation6 Months
Greatest Sum Divisible by Three6 Months
Delete Columns to Make Sorted6 Months
Sort the People
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Find the Maximum Sum of Node Values
Add Two Promises
Super Ugly Number
Defuse the Bomb6 Months
Keep Multiplying Found Values by Two6 Months
Minimum Array End
Find the Shortest Superstring
Minimum Length of String After Deleting Similar Ends6 Months
X of a Kind in a Deck of Cards
Ugly Number III
Maximum Sum of 3 Non-Overlapping Subarrays
Complex Number Multiplication
Apply Operations to an Array
Sort Vowels in a String
Minimum Time to Repair Cars
Count Subarrays Where Max Element Appears at Least K Times
Employees Whose Manager Left the Company
Maximum Absolute Sum of Any Subarray3 Months
Adding Spaces to a String
Remove Nodes From Linked List
Most Common Word
Take Gifts From the Richest Pile
Binary Tree Postorder Traversal
Reorder Data in Log Files
Transpose File
Detect Squares
Mini Parser
Rank Transform of an Array6 Months
The K Weakest Rows in a Matrix
Find the Minimum Amount of Time to Brew Potions6 Months
Trionic Array I3 Months
Vowels Game in a String
Binary Tree Pruning
Find Largest Value in Each Tree Row
Find X-Sum of All K-Long Subarrays I
Crawler Log Folder
Maximum XOR of Two Numbers in an Array
Counting Words With a Given Prefix
Egg Drop With 2 Eggs and N Floors
Check If All 1's Are at Least Length K Places Away
Find Most Frequent Vowel and Consonant6 Months
Minimum Removals to Balance Array30 Days
Design Circular Deque
Number of Subsequences That Satisfy the Given Sum Condition
Last Stone Weight II6 Months
Number of Laser Beams in a Bank
Check If a String Contains All Binary Codes of Size K
Divisible and Non-divisible Sums Difference
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Read N Characters Given Read4
Check if an Original String Exists Given Two Encoded Strings
Longest Palindrome by Concatenating Two Letter Words
Minimum Score After Removals on a Tree
Array Partition
Count Number of Rectangles Containing Each Point
String Matching in an Array
Maximum Value of an Ordered Triplet I
Eliminate Maximum Number of Monsters
Longest Repeating Substring
Sum of Absolute Differences in a Sorted Array
Remove Covered Intervals
Jump Game IV
Check if Two Chessboard Squares Have the Same Color
Construct Smallest Number From DI String
Find Minimum in Rotated Sorted Array II
Smallest Range II
Apply Operations to Make All Array Elements Equal to Zero
Number of Distinct Islands II
Number of Ways to Paint N × 3 Grid3 Months
Special Array With X Elements Greater Than or Equal X
Reverse String II
Minimum Cost to Hire K Workers
Number of Wonderful Substrings
Distant Barcodes6 Months
Number of Even and Odd Bits
Find the Peaks
Maximum Matching of Players With Trainers
Maximum Number of Fish in a Grid
4Sum II
Find Smallest Letter Greater Than Target3 Months
Longest Happy Prefix
Minimum Domino Rotations For Equal Row
Shortest Path Visiting All Nodes
Minimum Time Visiting All Points3 Months
Maximum Erasure Value
Count Special Triplets6 Months
Insert Greatest Common Divisors in Linked List
Maximum Difference Between Node and Ancestor
Maximum Running Time of N Computers3 Months
Minimum Number of Operations to Make Array XOR Equal to K
Customers Who Bought All Products
Clear Digits
Find All K-Distant Indices in an Array
Extra Characters in a String
Valid Palindrome IV
RLE Iterator
Average of Levels in Binary Tree
Reshape the Matrix
Find the Original Typed String II
Jump Game VI
Count Subarrays of Length Three With a Condition
Minimum Operations to Convert All Elements to Zero
Sort Array By Parity3 Months
Check Completeness of a Binary Tree6 Months
Total Hamming Distance6 Months
Number of Common Factors
Build Array from Permutation
Water Bottles II
Maximum Difference Between Increasing Elements
Lowest Common Ancestor of a Binary Tree IV
Convert the Temperature
Check if One String Swap Can Make Strings Equal
Count Partitions With Max-Min Difference at Most K3 Months
Separate Squares I6 Months
Sales Person
Check Knight Tour Configuration
Convert BST to Greater Tree
Convert 1D Array Into 2D Array
Length of the Longest Valid Substring
Minimum Number of Operations to Make Array Empty
Reformat Department Table
Stone Game
Minimum Swaps To Make Sequences Increasing
Number of Pairs Satisfying Inequality
Minimum Number of Vertices to Reach All Nodes6 Months
Find the Number of Ways to Place People I
Check if Number is a Sum of Powers of Three
Check If Digits Are Equal in String After Operations I6 Months
Sum of Total Strength of Wizards
The Earliest and Latest Rounds Where Players Compete
Final Value of Variable After Performing Operations
Triangle Judgement6 Months
Maximum Length of a Concatenated String with Unique Characters3 Months
Minimum Limit of Balls in a Bag
Add One Row to Tree
Complement of Base 10 Integer
Reduce Array Size to The Half
Find Root of N-Ary Tree
Self Dividing Numbers
Maximum Sum of Subsequence With Non-adjacent Elements
Minimum Sum of Four Digit Number After Splitting Digits
Largest Perimeter Triangle6 Months
Prime Palindrome
Root Equals Sum of Children6 Months
Concatenated Divisibility
Seat Reservation Manager
Movement of Robots
New 21 Game
Bitwise AND of Numbers Range
Maximum Level Sum of a Binary Tree
Nested List Weight Sum II
Tuple with Same Product
Perfect Rectangle
Construct Binary Tree from Preorder and Postorder Traversal
Maximum Difference Between Adjacent Elements in a Circular Array
Product Sales Analysis III
Find Building Where Alice and Bob Can Meet
Rank Transform of a Matrix
Shortest Distance in a Plane
Additive Number
To Lower Case
Fizz Buzz Multithreaded
Special Positions in a Binary Matrix
Smallest Subarrays With Maximum Bitwise OR
Count Number of Balanced Permutations
Longest Square Streak in an Array
Longest Palindrome After Substring Concatenation I
Count Total Number of Colored Cells
Painting a Grid With Three Different Colors
Maximum Twin Sum of a Linked List
Find the Number of Good Pairs II
Zero Array Transformation II
Number of Arithmetic Triplets
Generate Random Point in a Circle
Determine Whether Matrix Can Be Obtained By Rotation
Validate Binary Tree Nodes
Base 7
Four Divisors6 Months
Maximum Area of Longest Diagonal Rectangle
Minimum Consecutive Cards to Pick Up
Find Unique Binary String
Stream of Characters
Maximum 69 Number
Find Mode in Binary Search Tree
Find All Groups of Farmland
Split and Merge Array Transformation
Count Almost Equal Pairs I
Longest Subsequence With Limited Sum
Insertion Sort List6 Months
Best Time to Buy and Sell Stock V6 Months
Display the First Three Rows
Last Day Where You Can Still Cross6 Months
Minimum Cost Walk in Weighted Graph
Find the Pivot Integer
Partition Array into Two Equal Product Subsets
Smallest Number in Infinite Set
Find Maximal Uncovered Ranges
Largest Prime from Consecutive Prime Sum
Count Number of Trapezoids I
Apply Operations to Maximize Score
Find Sum of Array Product of Magical Sequences
Minimum Adjacent Swaps to Reach the Kth Smallest Number
Find the Largest Area of Square Inside Two Rectangles3 Months
Detect Capital
Length of Longest Fibonacci Subsequence
Sequential Digits
Minimum Operations to Make Array Elements Zero
Sum of k-Mirror Numbers
Sellers With No Sales
Maximum Number of Operations to Move Ones to the End6 Months
Minimum Number of Operations to Make Elements in Array Distinct
Tenth Line6 Months
Count of Interesting Subarrays
Largest Odd Number in String
Increment Submatrices by One6 Months
Longest Arithmetic Subsequence of Given Difference
Maximum Profit from Trading Stocks with Discounts
Minimum Recolors to Get K Consecutive Black Blocks
Count Number of Teams
Maximum Product of Three Elements After One Replacement
Count Largest Group
Make Array Elements Equal to Zero6 Months
Find Kth Bit in Nth Binary String
Unique Binary Search Trees II
Second Minimum Node In a Binary Tree
Range Module
Partition Array for Maximum Sum
K-th Symbol in Grammar
Domino and Tromino Tiling
Number of Dice Rolls With Target Sum
Hamming Distance
Number Complement
Unique Word Abbreviation
A Number After a Double Reversal
Timeout Cancellation
Minimum Number of Seconds to Make Mountain Height Zero
Find Closest Person
Longest Subarray With Maximum Bitwise AND
Minimum Operations to Make the Integer Zero6 Months
Implement Magic Dictionary
Number of Sub-arrays With Odd Sum
Arithmetic Slices II - Subsequence
Maximum Score Words Formed by Letters
Group Sold Products By The Date
Total Characters in String After Transformations II
Distribute Candies
Consecutive Characters
Apply Transform Over Each Element in Array
Sum of All Subset XOR Totals
Take K of Each Character From Left and Right
Find the K-th Character in String Game I6 Months
Reach End of Array With Max Score
Corporate Flight Bookings
Split a String Into the Max Number of Unique Substrings
Can Make Arithmetic Progression From Sequence3 Months
The Two Sneaky Numbers of Digitville
Zero Array Transformation III
Knight Dialer
Clone Binary Tree With Random Pointer
Construct the Minimum Bitwise Array II30 Days
Minimum Operations to Make Array Sum Divisible by K
Minimum Number of Moves to Seat Everyone
Stone Game III
Count the Number of Computer Unlocking Permutations6 Months
Beautiful Array
Queries Quality and Percentage
Find Books with No Available Copies6 Months
Rearrange Products Table
Minimize Maximum Pair Sum in Array6 Months
Goat Latin30 Days
Minimum Number Game
Number of Senior Citizens
Shortest Path to Get Food
Redundant Connection II
Longest Uncommon Subsequence I
Even Odd Tree
Number of Ways to Arrive at Destination
Friends Of Appropriate Ages3 Months
Longest Even Odd Subarray With Threshold
Ways to Express an Integer as Sum of Powers
Trionic Array II30 Days
Recover a Tree From Preorder Traversal
Delete Nodes From Linked List Present in Array6 Months
Total Distance Traveled
Number of Zero-Filled Subarrays
Reshape Data: Pivot
Make Two Arrays Equal by Reversing Subarrays
Solving Questions With Brainpower
Resulting String After Adjacent Removals
Transformed Array
Largest Color Value in a Directed Graph
Find Champion II
Find the Count of Good Integers
All Elements in Two Binary Search Trees
Flatten a Multilevel Doubly Linked List6 Months
Spiral Matrix IV
Mice and Cheese
Sleep
Count Alternating Subarrays
Longest Unequal Adjacent Groups Subsequence II
Find the Power of K-Size Subarrays I
Length of the Longest Subsequence That Sums to Target
Maximum Odd Binary Number
The Score of Students Solving Math Expression
Minimum Number of Pushes to Type Word II
Count Number of Trapezoids II3 Months
Rearrange Array Elements by Sign
Binary Tree Tilt
Minimum Operations to Make a Uni-Value Grid
Count Special Quadruplets
Minimum Moves to Equal Array Elements
Count Submatrices With All Ones
Maximum Vacation Days
Equal Row and Column Pairs
Longest Absolute File Path
Maximum Frequency of an Element After Performing Operations I6 Months
Smallest Value of the Rearranged Number
Transform Array to All Equal Elements
Check if the Sentence Is Pangram6 Months
Unpopular Books6 Months
Binary Watch
Lexicographically Smallest Equivalent String
Maximum Number of Distinct Elements After Operations
Final Array State After K Multiplication Operations II
Palindrome Permutation II
Sort Items by Groups Respecting Dependencies
Word Frequency
Similar String Groups
Count of Matches in Tournament
Find Longest Special Substring That Occurs Thrice I
Maximize the Confusion of an Exam
Find if Array Can Be Sorted
Move Pieces to Obtain a String
Minimum Average Difference
Finding 3-Digit Even Numbers
Divide an Array Into Subarrays With Minimum Cost I
Check If N and Its Double Exist
Swap Sex of Employees
Minimum Window Subsequence
Find the Punishment Number of an Integer
Count Number of Maximum Bitwise-OR Subsets
Count Prefix and Suffix Pairs I
Reschedule Meetings for Maximum Free Time I
Longest Balanced Substring I30 Days
Maximum Subarray Sum With Length Divisible by K6 Months