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DifficultyTopic261 of 261
No.ProblemDifficultyFrequency
42Trapping Rain WaterHard
100.0%
4Median of Two Sorted Arrays
ArrayHeap
Hard
75.0%
166Fraction to Recurring DecimalMedium
75.0%
387First Unique Character in a String
String
Easy
75.0%
1086High FiveEasy
75.0%
3Longest Substring Without Repeating Characters
StringTree
Medium
62.5%
11Container With Most WaterMedium
62.5%
33Search in Rotated Sorted Array
ArrayBinary Search
Medium
62.5%
49Group Anagrams
String
Medium
62.5%
56Merge IntervalsMedium
62.5%
64Minimum Path SumMedium
62.5%
91Decode WaysMedium
62.5%
146LRU CacheMedium
62.5%
200Number of Islands
GraphMath
Medium
62.5%
443String Compression
String
Medium
62.5%
1041Robot Bounded In CircleMedium
62.5%
1823Find the Winner of the Circular GameMedium
62.5%
1Two Sum
Sliding Window
Easy
50.0%
53Maximum Subarray
Array
Medium
50.0%
118Pascal's TriangleEasy
50.0%
121Best Time to Buy and Sell StockEasy
50.0%
122Best Time to Buy and Sell Stock IIMedium
50.0%
2087Minimum Cost Homecoming of a Robot in a GridMedium
50.0%
153Find Minimum in Rotated Sorted Array
ArrayBinary Search
Medium
50.0%
2097Valid Arrangement of PairsHard
50.0%
215Kth Largest Element in an Array
ArrayHeap
Medium
50.0%
2154Keep Multiplying Found Values by TwoEasy
50.0%
2266Count Number of Texts
Math
Medium
50.0%
2300Successful Pairs of Spells and PotionsMedium
50.0%
347Top K Frequent Elements
Heap
Medium
50.0%
2420Find All Good IndicesMedium
50.0%
2438Range Product Queries of Powers
Math
Medium
50.0%
2446Determine if Two Events Have ConflictEasy
50.0%
2484Count Palindromic Subsequences
String
Hard
50.0%
2550Count Collisions of Monkeys on a PolygonMedium
50.0%
657Robot Return to OriginEasy
50.0%
688Knight Probability in ChessboardMedium
50.0%
706Design HashMapEasy
50.0%
862Shortest Subarray with Sum at Least K
Array
Hard
50.0%
931Minimum Falling Path SumMedium
50.0%
1010Pairs of Songs With Total Durations Divisible by 60Medium
50.0%
1109Corporate Flight BookingsMedium
50.0%
1116Print Zero Even OddMedium
50.0%
3001Minimum Moves to Capture The QueenMedium
50.0%
1209Remove All Adjacent Duplicates in String II
String
Medium
50.0%
2191Sort the Jumbled Numbers
Math
Medium
50.0%
1427Perform String Shifts
String
Easy
50.0%
3168Minimum Number of Chairs in a Waiting Room
Math
Easy
50.0%
3167Better Compression of String
String
Medium
50.0%
1750Minimum Length of String After Deleting Similar Ends
String
Medium
50.0%
1771Maximize Palindrome Length From Subsequences
String
Hard
50.0%
465Optimal Account BalancingHard
50.0%
3437Permutations IIIMedium
50.0%
3494Find the Minimum Amount of Time to Brew PotionsMedium
50.0%
1094Car PoolingMedium
50.0%
516Longest Palindromic Subsequence
String
Medium
50.0%
2Add Two Numbers
Math
Medium
37.5%
5Longest Palindromic Substring
StringTree
Medium
37.5%
8String to Integer (atoi)
StringMath
Medium
37.5%
13Roman to Integer
Math
Easy
37.5%
153SumMedium
37.5%
20Valid Parentheses
Stack/Queue
Easy
37.5%
50Pow(x, n)
Math
Medium
37.5%
51N-QueensHard
37.5%
54Spiral Matrix
Array
Medium
37.5%
55Jump GameMedium
37.5%
62Unique PathsMedium
37.5%
69Sqrt(x)
Math
Easy
37.5%
70Climbing StairsEasy
37.5%
73Set Matrix Zeroes
Array
Medium
37.5%
135CandyHard
37.5%
141Linked List Cycle
GraphLinked List
Easy
37.5%
152Maximum Product Subarray
Array
Medium
37.5%
162Find Peak Element
Binary Search
Medium
37.5%
198House RobberMedium
37.5%
209Minimum Size Subarray Sum
Array
Medium
37.5%
218The Skyline ProblemHard
37.5%
238Product of Array Except Self
Array
Medium
37.5%
239Sliding Window Maximum
Sliding Window
Hard
37.5%
295Find Median from Data Stream
Heap
Hard
37.5%
74Search a 2D Matrix
Array
Medium
37.5%
394Decode String
String
Medium
37.5%
2375Construct Smallest Number From DI String
StringMath
Medium
37.5%
560Subarray Sum Equals K
Array
Medium
37.5%
647Palindromic Substrings
StringTree
Medium
37.5%
735Asteroid CollisionMedium
37.5%
739Daily TemperaturesMedium
37.5%
844Backspace String Compare
String
Easy
37.5%
994Rotting OrangesMedium
37.5%
1011Capacity To Ship Packages Within D DaysMedium
37.5%
1413Minimum Value to Get Positive Step by Step SumEasy
37.5%
1832Check if the Sentence Is PangramEasy
37.5%
424Longest Repeating Character ReplacementMedium
37.5%
273Integer to English Words
Math
Hard
37.5%
23Merge k Sorted ListsHard
37.5%
641Design Circular DequeMedium
37.5%
1235Maximum Profit in Job SchedulingHard
37.5%
206Reverse Linked List
Linked List
Easy
37.5%
22Generate ParenthesesMedium
37.5%
752Open the LockMedium
37.5%
457Circular Array Loop
Array
Medium
37.5%
128Longest Consecutive SequenceMedium
37.5%
1446Consecutive CharactersEasy
37.5%
414Third Maximum Number
Math
Easy
37.5%
283Move ZeroesEasy
37.5%
968Binary Tree Cameras
Tree
Hard
37.5%
322Coin Change
DP
Medium
37.5%
3371Identify the Largest Outlier in an Array
Array
Medium
37.5%
695Max Area of Island
Graph
Medium
37.5%
210Course Schedule IIMedium
37.5%
1343Number of Sub-arrays of Size K and Average Greater than or Equal to Threshold
ArrayMath
Medium
37.5%
240Search a 2D Matrix II
Array
Medium
37.5%
85Maximal RectangleHard
37.5%
354Russian Doll EnvelopesHard
37.5%
1478Allocate MailboxesHard
37.5%
611Valid Triangle Number
Math
Medium
37.5%
621Task SchedulerMedium
37.5%
1219Path with Maximum GoldMedium
37.5%
25Reverse Nodes in k-Group
Linked List
Hard
37.5%
875Koko Eating BananasMedium
37.5%
84Largest Rectangle in HistogramHard
37.5%
3649Number of Perfect Pairs
Math
Medium
37.5%
88Merge Sorted Array
Array
Easy
37.5%
134Gas StationMedium
37.5%
76Minimum Window Substring
StringTreeSliding Window
Hard
37.5%
3885Design Event ManagerMedium
37.5%
1665Minimum Initial Energy to Finish TasksHard
37.5%
12Integer to Roman
Math
Medium
25.0%
17Letter Combinations of a Phone Number
Math
Medium
25.0%
21Merge Two Sorted ListsEasy
25.0%
31Next PermutationMedium
25.0%
41First Missing PositiveHard
25.0%
45Jump Game IIMedium
25.0%
48Rotate ImageMedium
25.0%
79Word SearchMedium
25.0%
119Pascal's Triangle IIEasy
25.0%
143Reorder ListMedium
25.0%
160Intersection of Two Linked Lists
Linked List
Easy
25.0%
188Best Time to Buy and Sell Stock IVHard
25.0%
221Maximal SquareMedium
25.0%
268Missing Number
Math
Easy
25.0%
287Find the Duplicate Number
Math
Medium
25.0%
300Longest Increasing Subsequence
String
Medium
25.0%
326Power of Three
Math
Easy
25.0%
340Longest Substring with At Most K Distinct Characters
StringTree
Medium
25.0%
344Reverse String
String
Easy
25.0%
452Minimum Number of Arrows to Burst Balloons
Math
Medium
25.0%
496Next Greater Element IEasy
25.0%
2719Count of Integers
Math
Hard
25.0%
767Reorganize String
String
Medium
25.0%
780Reaching PointsHard
25.0%
1395Count Number of Teams
Math
Medium
25.0%
1396Design Underground SystemMedium
25.0%
205Isomorphic Strings
String
Easy
25.0%
564Find the Closest Palindrome
String
Hard
25.0%
37Sudoku SolverHard
25.0%
1004Max Consecutive Ones IIIMedium
25.0%
98Validate Binary Search Tree
TreeBinary Search
Medium
25.0%
264Ugly Number II
Math
Medium
25.0%
540Single Element in a Sorted Array
Array
Medium
25.0%
412Fizz BuzzEasy
25.0%
93Restore IP AddressesMedium
25.0%
325Maximum Size Subarray Sum Equals k
Array
Medium
25.0%
124Binary Tree Maximum Path Sum
Tree
Hard
25.0%
909Snakes and LaddersMedium
25.0%
78SubsetsMedium
25.0%
171Excel Sheet Column Number
Math
Easy
25.0%
918Maximum Sum Circular Subarray
Array
Medium
25.0%
460LFU CacheHard
25.0%
289Game of LifeMedium
25.0%
59Spiral Matrix II
Array
Medium
25.0%
336Palindrome Pairs
String
Hard
25.0%
456132 PatternMedium
25.0%
1838Frequency of the Most Frequent ElementMedium
25.0%
2043Simple Bank SystemMedium
25.0%
227Basic Calculator IIMedium
25.0%
1910Remove All Occurrences of a Substring
StringTree
Medium
25.0%
112Path SumEasy
25.0%
1448Count Good Nodes in Binary Tree
TreeLinked List
Medium
25.0%
653Two Sum IV - Input is a BST
TreeSliding Window
Easy
25.0%
503Next Greater Element IIMedium
25.0%
779K-th Symbol in GrammarMedium
25.0%
208Implement Trie (Prefix Tree)
Tree
Medium
25.0%
2402Meeting Rooms IIIHard
25.0%
622Design Circular Queue
Stack/Queue
Medium
25.0%
2734Lexicographically Smallest String After Substring Operation
StringTreeGraph
Medium
25.0%
277Find the CelebrityMedium
25.0%
120TriangleMedium
25.0%
1091Shortest Path in Binary Matrix
Array
Medium
25.0%
815Bus RoutesHard
25.0%
225Implement Stack using Queues
Stack/Queue
Easy
25.0%
150Evaluate Reverse Polish NotationMedium
25.0%
101Symmetric Tree
Tree
Easy
25.0%
34Find First and Last Position of Element in Sorted Array
Array
Medium
25.0%
102Binary Tree Level Order Traversal
Tree
Medium
25.0%
435Non-overlapping IntervalsMedium
25.0%
68Text JustificationHard
25.0%
416Partition Equal Subset Sum
DP
Medium
25.0%
312Burst BalloonsHard
25.0%
873Length of Longest Fibonacci Subsequence
StringDP
Medium
25.0%
123Best Time to Buy and Sell Stock IIIHard
25.0%
204Count Primes
Math
Medium
25.0%
979Distribute Coins in Binary Tree
Tree
Medium
25.0%
1262Greatest Sum Divisible by ThreeMedium
25.0%
127Word LadderHard
25.0%
2007Find Original Array From Doubled Array
Array
Medium
25.0%
1552Magnetic Force Between Two BallsMedium
25.0%
724Find Pivot IndexEasy
25.0%
1574Shortest Subarray to be Removed to Make Array Sorted
Array
Medium
25.0%
741Cherry PickupHard
25.0%
1146Snapshot Array
Array
Medium
25.0%
643Maximum Average Subarray I
Array
Easy
25.0%
47Permutations IIMedium
25.0%
169Majority ElementEasy
25.0%
279Perfect SquaresMedium
25.0%
1044Longest Duplicate Substring
StringTree
Hard
25.0%
703Kth Largest Element in a Stream
Heap
Easy
25.0%
2385Amount of Time for Binary Tree to Be Infected
Tree
Medium
25.0%
103Binary Tree Zigzag Level Order Traversal
Tree
Medium
25.0%
231Power of Two
Math
Easy
25.0%
980Unique Paths IIIHard
25.0%
2095Delete the Middle Node of a Linked List
Linked List
Medium
25.0%
1106Parsing A Boolean ExpressionHard
25.0%
2714Find Shortest Path with K HopsHard
25.0%
36Valid SudokuMedium
25.0%
1245Tree Diameter
Tree
Medium
25.0%
75Sort ColorsMedium
25.0%
1247Minimum Swaps to Make Strings Equal
String
Medium
25.0%
328Odd Even Linked List
Linked List
Medium
25.0%
399Evaluate DivisionMedium
25.0%
2093Minimum Cost to Reach City With DiscountsMedium
25.0%
1834Single-Threaded CPUMedium
25.0%
46PermutationsMedium
25.0%
1522Diameter of N-Ary Tree
Tree
Medium
25.0%
2193Minimum Number of Moves to Make Palindrome
StringMath
Hard
25.0%
973K Closest Points to OriginMedium
25.0%
945Minimum Increment to Make Array Unique
Array
Medium
25.0%
853Car FleetMedium
25.0%
1277Count Square Submatrices with All OnesMedium
25.0%
151Reverse Words in a String
String
Medium
25.0%
26Remove Duplicates from Sorted Array
Array
Easy
25.0%
1371Find the Longest Substring Containing Vowels in Even Counts
StringTree
Medium
25.0%
1312Minimum Insertion Steps to Make a String Palindrome
String
Hard
25.0%
934Shortest BridgeMedium
25.0%
1472Design Browser HistoryMedium
25.0%
236Lowest Common Ancestor of a Binary Tree
Tree
Medium
25.0%
678Valid Parenthesis String
String
Medium
25.0%
242Valid Anagram
String
Easy
25.0%
692Top K Frequent Words
Heap
Medium
25.0%
392Is Subsequence
String
Easy
25.0%
721Accounts MergeMedium
25.0%
179Largest Number
Math
Medium
25.0%
1483Kth Ancestor of a Tree Node
TreeLinked List
Hard
25.0%
410Split Array Largest Sum
Array
Hard
25.0%
1353Maximum Number of Events That Can Be Attended
Math
Medium
25.0%
1535Find the Winner of an Array Game
Array
Medium
25.0%
207Course ScheduleMedium
25.0%
713Subarray Product Less Than K
Array
Medium
25.0%
154Find Minimum in Rotated Sorted Array II
ArrayBinary Search
Hard
25.0%
738Monotone Increasing Digits
Math
Medium
25.0%
24Swap Nodes in Pairs
Linked List
Medium
25.0%