LeetCode

Schedule

题目解法分类

ID

Topics

• Two Sum Easy
• Add Two Numbers Medium
• Longest Substring Without Repeating Characters Medium
• Median of Two Sorted Arrays Hard
• Longest Palindromic Substring Medium
• Zigzag Conversion Medium
• Reverse Integer Medium
• String to Integer (atoi) Medium
• Palindrome Number Easy
• Regular Expression Matching Hard
• Container With Most Water Medium
• Integer to Roman Medium
• Roman to Integer Easy
• Longest Common Prefix Easy
• 3Sum Medium
• 3Sum Closest Medium
• Letter Combinations of a Phone Number Medium
• 4Sum Medium
• Remove Nth Node From End of List Medium
• Valid Parentheses Easy
• Merge Two Sorted Lists Easy
• Generate Parentheses Medium
• Merge k Sorted Lists Hard
• Swap Nodes in Pairs Medium
• Reverse Nodes in k-Group Hard
• Remove Duplicates from Sorted Array Easy
• Remove Element Easy
• Find the Index of the First Occurrence in a String Easy
• Divide Two Integers Medium
• Substring with Concatenation of All Words Hard
• Next Permutation Medium
• Longest Valid Parentheses Hard
• Search in Rotated Sorted Array Medium
• Find First and Last Position of Element in Sorted Array Medium
• Search Insert Position Easy
• Valid Sudoku Medium
• Sudoku Solver Hard
• Count and Say Medium
• Combination Sum Medium
• Combination Sum II Medium
• First Missing Positive Hard
• Trapping Rain Water Hard
• Multiply Strings Medium
• Wildcard Matching Hard
• Jump Game II Medium
• Permutations Medium
• Permutations II Medium
• Rotate Image Medium
• Group Anagrams Medium
• Pow(x, n) Medium
• N-Queens Hard
• N-Queens II Hard
• Maximum Subarray Medium
• Spiral Matrix Medium
• Jump Game Medium
• Merge Intervals Medium
• Insert Interval Medium
• Length of Last Word Easy
• Spiral Matrix II Medium
• Permutation Sequence Hard
• Rotate List Medium
• Unique Paths Medium
• Unique Paths II Medium
• Minimum Path Sum Medium
• Valid Number Hard
• Plus One Easy
• Add Binary Easy
• Text Justification Hard
• Sqrt(x) Easy
• Climbing Stairs Easy
• Simplify Path Medium
• Edit Distance Medium
• Set Matrix Zeroes Medium
• Search a 2D Matrix Medium
• Sort Colors Medium
• Minimum Window Substring Hard
• Combinations Medium
• Subsets Medium
• Word Search Medium
• Remove Duplicates from Sorted Array II Medium
• Search in Rotated Sorted Array II Medium
• Remove Duplicates from Sorted List II Medium
• Remove Duplicates from Sorted List Easy
• Largest Rectangle in Histogram Hard
• Maximal Rectangle Hard
• Partition List Medium
• Scramble String Hard
• Merge Sorted Array Easy
• Gray Code Medium
• Subsets II Medium
• Decode Ways Medium
• Reverse Linked List II Medium
• Restore IP Addresses Medium
• Binary Tree Inorder Traversal Easy
• Unique Binary Search Trees II Medium
• Unique Binary Search Trees Medium
• Interleaving String Medium
• Validate Binary Search Tree Medium
• Recover Binary Search Tree Medium
• Same Tree Easy
• Symmetric Tree Easy
• Binary Tree Level Order Traversal Medium
• Binary Tree Zigzag Level Order Traversal Medium
• Maximum Depth of Binary Tree Easy
• Construct Binary Tree from Preorder and Inorder Traversal Medium
• Construct Binary Tree from Inorder and Postorder Traversal Medium
• Binary Tree Level Order Traversal II Medium
• Convert Sorted Array to Binary Search Tree Easy
• Convert Sorted List to Binary Search Tree Medium
• Balanced Binary Tree Easy
• Minimum Depth of Binary Tree Easy
• Path Sum Easy
• Path Sum II Medium
• Flatten Binary Tree to Linked List Medium
• Distinct Subsequences Hard
• Populating Next Right Pointers in Each Node Medium
• Populating Next Right Pointers in Each Node II Medium
• Pascal's Triangle Easy
• Pascal's Triangle II Easy
• Triangle Medium
• Best Time to Buy and Sell Stock Easy
• Best Time to Buy and Sell Stock II Medium
• Best Time to Buy and Sell Stock III Hard
• Binary Tree Maximum Path Sum Hard
• Valid Palindrome Easy
• Word Ladder II Hard
• Word Ladder Hard
• Longest Consecutive Sequence Medium
• Sum Root to Leaf Numbers Medium
• Surrounded Regions Medium
• Palindrome Partitioning Medium
• Palindrome Partitioning II Hard
• Clone Graph Medium
• Gas Station Medium
• Candy Hard
• Single Number Easy
• Single Number II Medium
• Copy List with Random Pointer Medium
• Word Break Medium
• Word Break II Hard
• Linked List Cycle Easy
• Linked List Cycle II Medium
• Reorder List Medium
• Binary Tree Preorder Traversal Easy
• Binary Tree Postorder Traversal Easy
• LRU Cache Medium
• Insertion Sort List Medium
• Sort List Medium
• Max Points on a Line Hard
• Evaluate Reverse Polish Notation Medium
• Reverse Words in a String Medium
• Maximum Product Subarray Medium
• Find Minimum in Rotated Sorted Array Medium
• Find Minimum in Rotated Sorted Array II Hard
• Min Stack Medium
• Binary Tree Upside Down Medium
• Read N Characters Given Read4 Easy
• Read N Characters Given read4 II - Call Multiple Times Hard
• Longest Substring with At Most Two Distinct Characters Medium
• Intersection of Two Linked Lists Easy
• One Edit Distance Medium
• Find Peak Element Medium
• Missing Ranges Easy
• Maximum Gap Hard
• Compare Version Numbers Medium
• Fraction to Recurring Decimal Medium
• Two Sum II - Input Array Is Sorted Medium
• Excel Sheet Column Title Easy
• Majority Element Easy
• Two Sum III - Data structure design Easy
• Excel Sheet Column Number Easy
• Factorial Trailing Zeroes Medium
• Binary Search Tree Iterator Medium
• Dungeon Game Hard
• Combine Two Tables Easy
• Second Highest Salary Medium
• Nth Highest Salary Medium
• Rank Scores Medium
• Largest Number Medium
• Consecutive Numbers Medium
• Employees Earning More Than Their Managers Easy
• Duplicate Emails Easy
• Customers Who Never Order Easy
• Department Highest Salary Medium
• Department Top Three Salaries Hard
• Reverse Words in a String II Medium
• Repeated DNA Sequences Medium
• Best Time to Buy and Sell Stock IV Hard
• Rotate Array Medium
• Reverse Bits Easy
• Number of 1 Bits Easy
• Word Frequency Medium
• Valid Phone Numbers Easy
• Transpose File Medium
• Tenth Line Easy
• Delete Duplicate Emails Easy
• Rising Temperature Easy
• House Robber Medium
• Binary Tree Right Side View Medium
• Number of Islands Medium
• Bitwise AND of Numbers Range Medium
• Happy Number Easy
• Remove Linked List Elements Easy
• Count Primes Medium
• Isomorphic Strings Easy
• Reverse Linked List Easy
• Course Schedule Medium
• Implement Trie (Prefix Tree) Medium
• Minimum Size Subarray Sum Medium
• Course Schedule II Medium
• Design Add and Search Words Data Structure Medium
• Word Search II Hard
• House Robber II Medium
• Shortest Palindrome Hard
• Kth Largest Element in an Array Medium
• Combination Sum III Medium
• Contains Duplicate Easy
• The Skyline Problem Hard
• Contains Duplicate II Easy
• Contains Duplicate III Hard
• Maximal Square Medium
• Count Complete Tree Nodes Medium
• Rectangle Area Medium
• Basic Calculator Hard
• Implement Stack using Queues Easy
• Invert Binary Tree Easy
• Basic Calculator II Medium
• Summary Ranges Easy
• Majority Element II Medium
• Kth Smallest Element in a BST Medium
• Power of Two Easy
• Implement Queue using Stacks Easy
• Number of Digit One Hard
• Palindrome Linked List Easy
• Lowest Common Ancestor of a Binary Search Tree Medium
• Lowest Common Ancestor of a Binary Tree Medium
• Delete Node in a Linked List Medium
• Product of Array Except Self Medium
• Sliding Window Maximum Hard
• Search a 2D Matrix II Medium
• Different Ways to Add Parentheses Medium
• Valid Anagram Easy
• Shortest Word Distance Easy
• Shortest Word Distance II Medium
• Shortest Word Distance III Medium
• Strobogrammatic Number Easy
• Strobogrammatic Number II Medium
• Strobogrammatic Number III Hard
• Group Shifted Strings Medium
• Count Univalue Subtrees Medium
• Flatten 2D Vector Medium
• Meeting Rooms Easy
• Meeting Rooms II Medium
• Factor Combinations Medium
• Verify Preorder Sequence in Binary Search Tree Medium
• Paint House Medium
• Binary Tree Paths Easy
• Add Digits Easy
• 3Sum Smaller Medium
• Single Number III Medium
• Graph Valid Tree Medium
• Trips and Users Hard
• Ugly Number Easy
• Ugly Number II Medium
• Paint House II Hard
• Palindrome Permutation Easy
• Palindrome Permutation II Medium
• Missing Number Easy
• Alien Dictionary Hard
• Closest Binary Search Tree Value Easy
• Encode and Decode Strings Medium
• Closest Binary Search Tree Value II Hard
• Integer to English Words Hard
• H-Index Medium
• H-Index II Medium
• Paint Fence Medium
• Find the Celebrity Medium
• First Bad Version Easy
• Perfect Squares Medium
• Wiggle Sort Medium
• Zigzag Iterator Medium
• Expression Add Operators Hard
• Move Zeroes Easy
• Peeking Iterator Medium
• Inorder Successor in BST Medium
• Walls and Gates Medium
• Find the Duplicate Number Medium
• Unique Word Abbreviation Medium
• Game of Life Medium
• Word Pattern Easy
• Word Pattern II Medium
• Nim Game Easy
• Flip Game Easy
• Flip Game II Medium
• Find Median from Data Stream Hard
• Best Meeting Point Hard
• Serialize and Deserialize Binary Tree Hard
• Binary Tree Longest Consecutive Sequence Medium
• Bulls and Cows Medium
• Longest Increasing Subsequence Medium
• Remove Invalid Parentheses Hard
• Smallest Rectangle Enclosing Black Pixels Hard
• Range Sum Query - Immutable Easy
• Range Sum Query 2D - Immutable Medium
• Number of Islands II Hard
• Additive Number Medium
• Range Sum Query - Mutable Medium
• Range Sum Query 2D - Mutable Hard
• Best Time to Buy and Sell Stock with Cooldown Medium
• Minimum Height Trees Medium
• Sparse Matrix Multiplication Medium
• Burst Balloons Hard
• Super Ugly Number Medium
• Binary Tree Vertical Order Traversal Medium
• Count of Smaller Numbers After Self Hard
• Remove Duplicate Letters Medium
• Shortest Distance from All Buildings Hard
• Maximum Product of Word Lengths Medium
• Bulb Switcher Medium
• Generalized Abbreviation Medium
• Create Maximum Number Hard
• Coin Change Medium
• Number of Connected Components in an Undirected Graph Medium
• Wiggle Sort II Medium
• Maximum Size Subarray Sum Equals k Medium
• Power of Three Easy
• Count of Range Sum Hard
• Odd Even Linked List Medium
• Longest Increasing Path in a Matrix Hard
• Patching Array Hard
• Verify Preorder Serialization of a Binary Tree Medium
• Reconstruct Itinerary Hard
• Largest BST Subtree Medium
• Increasing Triplet Subsequence Medium
• Self Crossing Hard
• Palindrome Pairs Hard
• House Robber III Medium
• Counting Bits Easy
• Nested List Weight Sum Medium
• Longest Substring with At Most K Distinct Characters Medium
• Flatten Nested List Iterator Medium
• Power of Four Easy
• Integer Break Medium
• Reverse String Easy
• Reverse Vowels of a String Easy
• Moving Average from Data Stream Easy
• Top K Frequent Elements Medium
• Design Tic-Tac-Toe Medium
• Intersection of Two Arrays Easy
• Intersection of Two Arrays II Easy
• Android Unlock Patterns Medium
• Data Stream as Disjoint Intervals Hard
• Design Snake Game Medium
• Russian Doll Envelopes Hard
• Design Twitter Medium
• Line Reflection Medium
• Count Numbers with Unique Digits Medium
• Rearrange String k Distance Apart Hard
• Logger Rate Limiter Easy
• Sort Transformed Array Medium
• Bomb Enemy Medium
• Design Hit Counter Medium
• Max Sum of Rectangle No Larger Than K Hard
• Nested List Weight Sum II Medium
• Water and Jug Problem Medium
• Find Leaves of Binary Tree Medium
• Valid Perfect Square Easy
• Largest Divisible Subset Medium
• Plus One Linked List Medium
• Range Addition Medium
• Sum of Two Integers Medium
• Super Pow Medium
• Find K Pairs with Smallest Sums Medium
• Guess Number Higher or Lower Easy
• Guess Number Higher or Lower II Medium
• Wiggle Subsequence Medium
• Combination Sum IV Medium
• Kth Smallest Element in a Sorted Matrix Medium
• Design Phone Directory Medium
• Insert Delete GetRandom O(1) Medium
• Insert Delete GetRandom O(1) - Duplicates allowed Hard
• Linked List Random Node Medium
• Ransom Note Easy
• Shuffle an Array Medium
• Mini Parser Medium
• Lexicographical Numbers Medium
• First Unique Character in a String Easy
• Longest Absolute File Path Medium
• Find the Difference Easy
• Elimination Game Medium
• Perfect Rectangle Hard
• Is Subsequence Easy
• UTF-8 Validation Medium
• Decode String Medium
• Longest Substring with At Least K Repeating Characters Medium
• Rotate Function Medium
• Integer Replacement Medium
• Random Pick Index Medium
• Evaluate Division Medium
• Nth Digit Medium
• Binary Watch Easy
• Remove K Digits Medium
• Frog Jump Hard
• Sum of Left Leaves Easy
• Convert a Number to Hexadecimal Easy
• Queue Reconstruction by Height Medium
• Trapping Rain Water II Hard
• Valid Word Abbreviation Easy
• Longest Palindrome Easy
• Fizz Buzz Easy
• Arithmetic Slices Medium
• Third Maximum Number Easy
• Add Strings Easy
• Partition Equal Subset Sum Medium
• Pacific Atlantic Water Flow Medium
• Sentence Screen Fitting Medium
• Battleships in a Board Medium
• Maximum XOR of Two Numbers in an Array Medium
• Valid Word Square Easy
• Reconstruct Original Digits from English Medium
• Longest Repeating Character Replacement Medium
• Convert Binary Search Tree to Sorted Doubly Linked List Medium
• Construct Quad Tree Medium
• N-ary Tree Level Order Traversal Medium
• Flatten a Multilevel Doubly Linked List Medium
• Minimum Genetic Mutation Medium
• Number of Segments in a String Easy
• Non-overlapping Intervals Medium
• Find Right Interval Medium
• Path Sum III Medium
• Find All Anagrams in a String Medium
• Ternary Expression Parser Medium
• Arranging Coins Easy
• Find All Duplicates in an Array Medium
• String Compression Medium
• Sequence Reconstruction Medium
• Add Two Numbers II Medium
• Number of Boomerangs Medium
• Find All Numbers Disappeared in an Array Easy
• Serialize and Deserialize BST Medium
• Delete Node in a BST Medium
• Sort Characters By Frequency Medium
• Minimum Number of Arrows to Burst Balloons Medium
• Minimum Moves to Equal Array Elements Medium
• 4Sum II Medium
• Assign Cookies Easy
• 132 Pattern Medium
• Circular Array Loop Medium
• Repeated Substring Pattern Easy
• Hamming Distance Easy
• Minimum Moves to Equal Array Elements II Medium
• Island Perimeter Easy
• Can I Win Medium
• Unique Substrings in Wraparound String Medium
• Validate IP Address Medium
• Convex Polygon Medium
• Implement Rand10() Using Rand7() Medium
• Matchsticks to Square Medium
• Ones and Zeroes Medium
• Heaters Medium
• Number Complement Easy
• Total Hamming Distance Medium
• Generate Random Point in a Circle Medium
• Magical String Medium
• License Key Formatting Easy
• Find Permutation Medium
• Max Consecutive Ones Easy
• Predict the Winner Medium
• Max Consecutive Ones II Medium
• The Maze Medium
• Non-decreasing Subsequences Medium
• Construct the Rectangle Easy
• Target Sum Medium
• Teemo Attacking Easy
• Next Greater Element I Easy
• Random Point in Non-overlapping Rectangles Medium
• Diagonal Traverse Medium
• Keyboard Row Easy
• Find Mode in Binary Search Tree Easy
• Next Greater Element II Medium
• Base 7 Easy
• The Maze II Medium
• Relative Ranks Easy
• Perfect Number Easy
• Most Frequent Subtree Sum Medium
• Fibonacci Number Easy
• Inorder Successor in BST II Medium
• Game Play Analysis I Easy
• Game Play Analysis II Easy
• Find Bottom Left Tree Value Medium
• Find Largest Value in Each Tree Row Medium
• Longest Palindromic Subsequence Medium
• Coin Change II Medium
• Random Flip Matrix Medium
• Detect Capital Easy
• Longest Uncommon Subsequence I Easy
• Longest Uncommon Subsequence II Medium
• Continuous Subarray Sum Medium
• Longest Word in Dictionary through Deleting Medium
• Contiguous Array Medium
• Beautiful Arrangement Medium
• Random Pick with Weight Medium
• Minesweeper Medium
• Minimum Absolute Difference in BST Easy
• Lonely Pixel I Medium
• K-diff Pairs in an Array Medium
• Lonely Pixel II Medium
• Game Play Analysis III Medium
• Encode and Decode TinyURL Medium
• Construct Binary Tree from String Medium
• Complex Number Multiplication Medium
• Convert BST to Greater Tree Medium
• Minimum Time Difference Medium
• Single Element in a Sorted Array Medium
• Reverse String II Easy
• 01 Matrix Medium
• Diameter of Binary Tree Easy
• Output Contest Matches Medium
• Boundary of Binary Tree Medium
• Number of Provinces Medium
• Binary Tree Longest Consecutive Sequence II Medium
• Student Attendance Record I Easy
• Optimal Division Medium
• Brick Wall Medium
• Split Concatenated Strings Medium
• Next Greater Element III Medium
• Reverse Words in a String III Easy
• Logical OR of Two Binary Grids Represented as Quad-Trees Medium
• Maximum Depth of N-ary Tree Easy
• Subarray Sum Equals K Medium
• Array Partition Easy
• Longest Line of Consecutive One in Matrix Medium
• Binary Tree Tilt Easy
• Array Nesting Medium
• Reshape the Matrix Easy
• Permutation in String Medium
• Median Employee Salary Hard
• Managers with at Least 5 Direct Reports Medium
• Find Median Given Frequency of Numbers Hard
• Subtree of Another Tree Easy
• Squirrel Simulation Medium
• Winning Candidate Medium
• Distribute Candies Easy
• Out of Boundary Paths Medium
• Employee Bonus Easy
• Get Highest Answer Rate Question Medium
• Find Cumulative Salary of an Employee Hard
• Count Student Number in Departments Medium
• Shortest Unsorted Continuous Subarray Medium
• Kill Process Medium
• Delete Operation for Two Strings Medium
• Find Customer Referee Easy
• Investments in 2016 Medium
• Customer Placing the Largest Number of Orders Easy
• N-ary Tree Preorder Traversal Easy
• N-ary Tree Postorder Traversal Easy
• Fraction Addition and Subtraction Medium
• Valid Square Medium
• Longest Harmonious Subsequence Easy
• Big Countries Easy
• Classes More Than 5 Students Easy
• Friend Requests I: Overall Acceptance Rate Easy
• Range Addition II Easy
• Minimum Index Sum of Two Lists Easy
• Human Traffic of Stadium Hard
• Friend Requests II: Who Has the Most Friends Medium
• Consecutive Available Seats Easy
• Design Compressed String Iterator Easy
• Can Place Flowers Easy
• Construct String from Binary Tree Easy
• Sales Person Easy
• Tree Node Medium
• Find Duplicate File in System Medium
• Triangle Judgement Easy
• Valid Triangle Number Medium
• Shortest Distance in a Plane Medium
• Shortest Distance in a Line Easy
• Second Degree Follower Medium
• Average Salary: Departments VS Company Hard
• Add Bold Tag in String Medium
• Merge Two Binary Trees Easy
• Students Report By Geography Hard
• Biggest Single Number Easy
• Not Boring Movies Easy
• Task Scheduler Medium
• Design Circular Queue Medium
• Add One Row to Tree Medium
• Maximum Distance in Arrays Medium
• Minimum Factorization Medium
• Exchange Seats Medium
• Swap Salary Easy
• Maximum Product of Three Numbers Easy
• Sum of Square Numbers Medium
• Find the Derangement of An Array Medium
• Design Log Storage System Medium
• Exclusive Time of Functions Medium
• Average of Levels in Binary Tree Easy
• Shopping Offers Medium
• Solve the Equation Medium
• Design Circular Deque Medium
• Maximum Average Subarray I Easy
• Set Mismatch Easy
• Maximum Length of Pair Chain Medium
• Palindromic Substrings Medium
• Replace Words Medium
• Dota2 Senate Medium
• 2 Keys Keyboard Medium
• 4 Keys Keyboard Medium
• Find Duplicate Subtrees Medium
• Two Sum IV - Input is a BST Easy
• Maximum Binary Tree Medium
• Print Binary Tree Medium
• Robot Return to Origin Easy
• Find K Closest Elements Medium
• Split Array into Consecutive Subsequences Medium
• Image Smoother Easy
• Maximum Width of Binary Tree Medium
• Equal Tree Partition Medium
• Non-decreasing Array Medium
• Path Sum IV Medium
• Beautiful Arrangement II Medium
• Trim a Binary Search Tree Medium
• Maximum Swap Medium
• Second Minimum Node In a Binary Tree Easy
• Bulb Switcher II Medium
• Number of Longest Increasing Subsequence Medium
• Longest Continuous Increasing Subsequence Easy
• Implement Magic Dictionary Medium
• Map Sum Pairs Medium
• Valid Parenthesis String Medium
• Valid Palindrome II Easy
• Next Closest Time Medium
• Baseball Game Easy
• Redundant Connection Medium
• Repeated String Match Medium
• Longest Univalue Path Medium
• Knight Probability in Chessboard Medium
• Employee Importance Medium
• Stickers to Spell Word Hard
• Top K Frequent Words Medium
• Binary Number with Alternating Bits Easy
• Number of Distinct Islands Medium
• Max Area of Island Medium
• Count Binary Substrings Easy
• Degree of an Array Easy
• Partition to K Equal Sum Subsets Medium
• Falling Squares Hard
• Search in a Binary Search Tree Easy
• Insert into a Binary Search Tree Medium
• Search in a Sorted Array of Unknown Size Medium
• Kth Largest Element in a Stream Easy
• Binary Search Easy
• Design HashSet Easy
• Design HashMap Easy
• Design Linked List Medium
• Insert into a Sorted Circular Linked List Medium
• To Lower Case Easy
• Random Pick with Blacklist Hard
• Number of Distinct Islands II Hard
• Minimum ASCII Delete Sum for Two Strings Medium
• Subarray Product Less Than K Medium
• Best Time to Buy and Sell Stock with Transaction Fee Medium
• Range Module Hard
• Max Stack Hard
• 1-bit and 2-bit Characters Easy
• Maximum Length of Repeated Subarray Medium
• Longest Word in Dictionary Medium
• Accounts Merge Medium
• Remove Comments Medium
• Candy Crush Medium
• Find Pivot Index Easy
• Split Linked List in Parts Medium
• Self Dividing Numbers Easy
• My Calendar I Medium
• My Calendar II Medium
• Flood Fill Easy
• Sentence Similarity Easy
• Asteroid Collision Medium
• Sentence Similarity II Medium
• Monotone Increasing Digits Medium
• Daily Temperatures Medium
• Delete and Earn Medium
• Closest Leaf in a Binary Tree Medium
• Network Delay Time Medium
• Find Smallest Letter Greater Than Target Easy
• Min Cost Climbing Stairs Easy
• Largest Number At Least Twice of Others Easy
• Shortest Completing Word Easy
• Number Of Corner Rectangles Medium
• IP to CIDR Medium
• Open the Lock Medium
• Reach a Number Medium
• Pour Water Medium
• Pyramid Transition Matrix Medium
• Bold Words in String Medium
• Find Anagram Mappings Easy
• Prime Number of Set Bits in Binary Representation Easy
• Partition Labels Medium
• Largest Plus Sign Medium
• Toeplitz Matrix Easy
• Reorganize String Medium
• Max Chunks To Make Sorted Medium
• Jewels and Stones Easy
• Sliding Puzzle Hard
• Global and Local Inversions Medium
• Split BST Medium
• Swap Adjacent in LR String Medium
• K-th Symbol in Grammar Medium
• Rabbits in Forest Medium
• Minimum Distance Between BST Nodes Easy
• Letter Case Permutation Medium
• Is Graph Bipartite? Medium
• K-th Smallest Prime Fraction Medium
• Cheapest Flights Within K Stops Medium
• Rotated Digits Medium
• Escape The Ghosts Medium
• Domino and Tromino Tiling Medium
• Custom Sort String Medium
• Number of Matching Subsequences Medium
• Valid Tic-Tac-Toe State Medium
• Number of Subarrays with Bounded Maximum Medium
• Rotate String Easy
• All Paths From Source to Target Medium
• Champagne Tower Medium
• Similar RGB Color Easy
• Minimum Swaps To Make Sequences Increasing Hard
• Most Common Word * Easy
• Shortest Distance to a Character Easy
• Friends Of Appropriate Ages Medium
• Making A Large Island Hard
• Flipping an Image Easy
• Find And Replace in String Medium
• Rectangle Overlap Easy
• Guess the Word Hard
• Backspace String Compare Easy
• Longest Mountain in Array Medium
• Maximize Distance to Closest Person Medium
• Peak Index in a Mountain Array Medium
• Car Fleet Medium
• Exam Room Medium
• Score of Parentheses * Medium
• Shortest Subarray with Sum at Least K Hard
• All Nodes Distance K in Binary Tree ** Medium
• Transpose Matrix Easy
• Leaf-Similar Trees Easy
• Middle of the Linked List Easy
• Boats to Save People Medium
• Spiral Matrix III Medium
• Possible Bipartition Medium
• Fair Candy Swap Easy
• Find and Replace Pattern Medium
• Online Stock Span Medium
• Minimum Add to Make Parentheses Valid Medium
• Range Sum of BST Easy
• Verifying an Alien Dictionary Easy
• K Closest Points to Origin Medium
• Subarray Sums Divisible by K Medium
• Interval List Intersections Medium
• Vertical Order Traversal of a Binary Tree Hard
• Cousins in Binary Tree Easy
• Grid Illumination Hard
• Find Common Characters Easy
• Max Consecutive Ones III * Medium
• Clumsy Factorial Medium
• Construct Binary Search Tree from Preorder Traversal Medium
• Complement of Base 10 Integer Easy
• Partition Array Into Three Parts With Equal Sum Easy
• Next Greater Node In Linked List Medium
• Number of Enclaves Medium
• Longest Arithmetic Subsequence Medium
• Maximum Sum of Two Non-Overlapping Subarrays Medium
• Binary Search Tree to Greater Sum Tree Medium
• Customers Who Bought All Products Medium
• Remove All Adjacent Duplicates In String Easy
• Actors and Directors Who Cooperated At Least Three Times Easy
• Previous Permutation With One Swap Medium
• Product Sales Analysis I Easy
• Product Sales Analysis II Easy
• Product Sales Analysis III Medium
• Project Employees I Easy
• Project Employees II Easy
• Project Employees III Medium
• Smallest Subsequence of Distinct Characters Medium
• Sales Analysis I Easy
• Sales Analysis II Easy
• Sales Analysis III Easy
• Duplicate Zeros Easy
• Shortest Path in Binary Matrix Medium
• Game Play Analysis V Hard
• Unpopular Books Medium
• The Earliest Moment When Everyone Become Friends Medium
• New Users Daily Count Medium
• Delete Nodes And Return Forest Medium
• Highest Grade For Each Student Medium
• Reported Posts Easy
• Print in Order Easy
• Print FooBar Alternately Medium
• Print Zero Even Odd Medium
• Building H2O Medium
• Active Businesses Medium
• User Purchase Platform Hard
• Reported Posts II Medium
• Parallel Courses Medium
• User Activity for the Past 30 Days I Easy
• User Activity for the Past 30 Days II Easy
• Longest Common Subsequence Medium
• Article Views I Easy
• Article Views II Medium
• Market Analysis I Medium
• Market Analysis II Hard
• Product Price at a Given Date Medium
• Immediate Food Delivery I Easy
• Immediate Food Delivery II Medium
• Reformat Department Table Easy
• Design Bounded Blocking Queue Medium
• Monthly Transactions I Medium
• Tournament Winners Hard
• Fizz Buzz Multithreaded Medium
• Ugly Number III Medium
• Smallest String With Swaps Medium
• Last Person to Fit in the Bus Medium
• Monthly Transactions II Medium
• Design Skiplist Medium
• Queries Quality and Percentage Easy
• Team Scores in Football Tournament Medium
• Valid Palindrome III Hard
• Report Contiguous Dates Hard
• The Dining Philosophers Medium
• Number of Comments per Post Easy
• Web Crawler Multithreaded Medium
• Minimum Remove to Make Valid Parentheses Medium
• Average Selling Price Easy
• Number of Closed Islands Medium
• Page Recommendations Medium
• All People Report to the Given Manager Medium
• Traffic Light Controlled Intersection Easy
• Students and Examinations Easy
• Find the Start and End Number of Continuous Ranges Medium
• Weather Type in Each Country Easy
• Number of Paths with Max Score Hard
• Find the Team Size Easy
• Find N Unique Integers Sum up to Zero Easy
• Running Total for Different Genders Medium
• Restaurant Growth Medium
• Ads Performance Easy
• List the Products Ordered in a Period Easy
• Number of Transactions per Visit Hard
• Movie Rating Medium
• Students With Invalid Departments Easy
• Activity Participants Medium
• Number of Trusted Contacts of a Customer Medium
• Get the Second Most Recent Activity Hard
• Replace Employee ID With The Unique Identifier Easy
• Total Sales Amount by Year Hard
• Capital Gain/Loss Medium
• Find Lucky Integer in an Array Easy
• Customers Who Bought Products A and B but Not C Medium
• Circle and Rectangle Overlapping Medium
• Top Travellers Easy
• Find the Quiet Students in All Exams Hard
• Reformat The String Easy
• NPV Queries Easy
• Diagonal Traverse II Medium
• Create a Session Bar Chart Easy
• Evaluate Boolean Expression Medium
• Apples & Oranges Medium
• Active Users Medium
• Rectangles Area Medium
• Calculate Salaries Medium
• Sales by Day of the Week Hard
• Group Sold Products By The Date Easy
• Friendly Movies Streamed Last Month Easy
• Countries You Can Safely Invest In Medium
• Customer Order Frequency Easy
• Find Users With Valid E-Mails Easy
• Patients With a Condition Easy
• String Compression II Hard
• The Most Recent Three Orders Medium
• Kth Missing Positive Number Easy
• Fix Product Name Format Easy
• The Most Recent Orders for Each Product Medium
• Bank Account Summary Medium
• Unique Orders and Customers Per Month Easy
• Dot Product of Two Sparse Vectors Medium
• Warehouse Manager Easy
• Customer Who Visited but Did Not Make Any Transactions Easy
• Bank Account Summary II Easy
• The Most Frequently Ordered Products for Each Customer Medium
• Maximum Number of Achievable Transfer Requests Hard
• Sellers With No Sales Easy
• Maximum Number of Visible Points Hard
• Find the Missing IDs Medium
• All Valid Triplets That Can Represent a Country Easy
• Percentage of Users Attended a Contest Easy
• Hopper Company Queries I Hard
• Hopper Company Queries II Hard
• Lowest Common Ancestor of a Binary Tree III Medium
• Hopper Company Queries III Hard
• Determine if Two Strings Are Close Medium
• Average Time of Process per Machine Easy
• Fix Names in a Table Easy
• Product's Worth Over Invoices Easy
• Invalid Tweets Easy
• Daily Leads and Partners Easy
• Number of Calls Between Two Persons Medium
• Average Waiting Time Medium
• Biggest Window Between Visits Medium
• Count Apples and Oranges Medium
• Swapping Nodes in a Linked List Medium
• Find Followers Count Easy
• The Number of Employees Which Report to Each Employee Easy
• Find Total Time Spent by Each Employee Easy
• Leetflex Banned Accounts Medium
• Recyclable and Low Fat Products Easy
• Buildings With an Ocean View Medium
• Form Array by Concatenating Subarrays of Another Array Medium
• Find the Subtasks That Did Not Execute Hard
• Merge Strings Alternately Easy
• Car Fleet II Hard
• Product's Price for Each Store Easy
• Find Nearest Point That Has the Same X or Y Coordinate Easy
• Grand Slam Titles Medium
• Primary Department for Each Employee Easy
• Rearrange Products Table Easy
• Number of Orders in the Backlog Medium
• Ad-Free Sessions Easy
• Find Interview Candidates Medium
• Find Customers With Positive Revenue this Year Easy
• Maximum Transaction Each Day Medium
• League Statistics Medium
• Suspicious Bank Accounts Medium
• Convert Date Format Easy
• Largest Color Value in a Directed Graph Hard
• Orders With Maximum Quantity Above Average Medium
• Product of Two Run-Length Encoded Arrays Medium
• Calculate Special Bonus Easy
• Group Employees of the Same Salary Medium
• The Latest Login in 2020 Easy
• Page Recommendations II Hard
• Find a Peak Element II Medium
• Count Salary Categories Medium
• Leetcodify Friends Recommendations Hard
• Leetcodify Similar Friends Hard
• Confirmation Rate Medium
• Users That Actively Request Confirmation Messages Easy
• Strong Friendship Medium
• All the Pairs With the Maximum Number of Common Followers Medium
• Employees With Missing Information Easy
• First and Last Call On the Same Day Hard
• Employees Whose Manager Left the Company Easy
• Find Cutoff Score for Each School Medium
• Count the Number of Experiments Medium
• The Number of Seniors and Juniors to Join the Company Hard
• The Number of Seniors and Juniors to Join the Company II Hard
• Number of Accounts That Did Not Stream Medium
• Low-Quality Problems Easy
• Accepted Candidates From the Interviews Medium
• The Category of Each Member in the Store Medium
• Account Balance Medium
• The Winner University Easy
• The Number of Rich Customers Easy
• Drop Type 1 Orders for Customers With Type 0 Orders Medium
• Detonate the Maximum Bombs Medium
• The Airport With the Most Traffic Medium
• Build the Equation Hard
• The Number of Passengers in Each Bus I Medium
• The Number of Passengers in Each Bus II Hard
• Order Two Columns Independently Medium
• Longest Winning Streak Hard
• The Change in Global Rankings Medium
• Finding the Topic of Each Post Hard
• The Number of Users That Are Eligible for Discount Easy
• Users With Two Purchases Within Seven Days Medium
• The Users That Are Eligible for Discount Easy
• Add Two Integers Easy
• Number of Times a Driver Was a Passenger Medium
• Dynamic Pivoting of a Table Hard
• Dynamic Unpivoting of a Table Hard
• Check if Number Has Equal Digit Count and Digit Value Easy
• Products With Three or More Orders in Two Consecutive Years Medium
• Tasks Count in the Weekend Medium
• Arrange Table by Gender Medium
• The First Day of the Maximum Recorded Degree in Each City Medium
• Product Sales Analysis IV Medium
• Product Sales Analysis V Easy
• The Latest Time to Catch a Bus Medium
• All the Matches of the League Easy
• Compute the Rank as a Percentage Medium
• Number of Unique Subjects Taught by Each Teacher Easy
• Generate the Invoice Hard
• Task Scheduler II Medium
• Calculate the Influence of Each Salesperson Medium
• Sort the Olympic Table Easy
• Change Null Values in a Table to the Previous Value Medium
• Employees With Deductions Medium
• Meeting Rooms III Hard
• Height of Binary Tree After Subtree Removal Queries Hard