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DifficultyTopic191 of 191
No.ProblemDifficultyFrequency
2571Minimum Operations to Reduce an Integer to 0
Math
Medium
100.0%
443String Compression
String
Medium
87.5%
460LFU CacheHard
75.0%
2957Remove Adjacent Almost-Equal CharactersMedium
75.0%
3398Smallest Substring With Identical Characters I
StringTree
Hard
75.0%
3399Smallest Substring With Identical Characters II
StringTree
Hard
75.0%
3488Closest Equal Element QueriesMedium
75.0%
2380Time Needed to Rearrange a Binary String
String
Medium
75.0%
3Longest Substring Without Repeating Characters
StringTree
Medium
62.5%
49Group Anagrams
String
Medium
62.5%
56Merge IntervalsMedium
62.5%
115Distinct Subsequences
String
Hard
62.5%
2068Check Whether Two Strings are Almost Equivalent
String
Easy
62.5%
146LRU CacheMedium
62.5%
200Number of Islands
GraphMath
Medium
62.5%
210Course Schedule IIMedium
62.5%
628Maximum Product of Three Numbers
Math
Easy
62.5%
647Palindromic Substrings
StringTree
Medium
62.5%
2563Count the Number of Fair Pairs
Math
Medium
62.5%
713Subarray Product Less Than K
Array
Medium
62.5%
895Maximum Frequency Stack
Stack/Queue
Hard
62.5%
2866Beautiful Towers IIMedium
62.5%
2865Beautiful Towers IMedium
62.5%
1150Check If a Number Is Majority Element in a Sorted Array
ArrayMath
Easy
62.5%
1051Height CheckerEasy
62.5%
2946Matrix Similarity After Cyclic Shifts
Array
Easy
62.5%
2992Number of Self-Divisible Permutations
Math
Medium
62.5%
3125Maximum Number That Makes Result of Bitwise AND Zero
Math
Medium
62.5%
3171Find Subarray With Bitwise OR Closest to K
Array
Hard
62.5%
3135Equalize Strings by Adding or Removing Characters at Ends
String
Medium
62.5%
3193Count the Number of Inversions
Math
Hard
62.5%
3197Find the Minimum Area to Cover All Ones IIHard
62.5%
3195Find the Minimum Area to Cover All Ones IMedium
62.5%
3200Maximum Height of a TriangleEasy
62.5%
1659Maximize Grid HappinessHard
62.5%
1701Average Waiting TimeMedium
62.5%
924Minimize Malware SpreadHard
62.5%
1297Maximum Number of Occurrences of a Substring
StringTreeMath
Medium
62.5%
1221Split a String in Balanced Strings
String
Easy
62.5%
3540Minimum Time to Visit All HousesMedium
62.5%
3607Power Grid Maintenance
Math
Medium
62.5%
3613Minimize Maximum Component CostMedium
62.5%
740Delete and EarnMedium
62.5%
3035Maximum Palindromes After Operations
String
Medium
62.5%
5Longest Palindromic Substring
StringTree
Medium
50.0%
42Trapping Rain WaterHard
50.0%
76Minimum Window Substring
StringTreeSliding Window
Hard
50.0%
124Binary Tree Maximum Path Sum
Tree
Hard
50.0%
121Best Time to Buy and Sell StockEasy
50.0%
155Min Stack
Stack/Queue
Medium
50.0%
215Kth Largest Element in an Array
ArrayHeap
Medium
50.0%
347Top K Frequent Elements
Heap
Medium
50.0%
735Asteroid CollisionMedium
50.0%
1326Minimum Number of Taps to Open to Water a Garden
Math
Hard
50.0%
2966Divide Array Into Arrays With Max Difference
Array
Medium
50.0%
233Number of Digit One
Math
Hard
50.0%
1Two Sum
Sliding Window
Easy
50.0%
1710Maximum Units on a TruckEasy
50.0%
3313Find the Last Marked Nodes in Tree
TreeLinked List
Hard
50.0%
2964Number of Divisible Triplet Sums
Math
Medium
50.0%
79Word SearchMedium
50.0%
532K-diff Pairs in an Array
Array
Medium
50.0%
25Reverse Nodes in k-Group
Linked List
Hard
50.0%
1200Minimum Absolute DifferenceEasy
50.0%
6Zigzag ConversionMedium
50.0%
863All Nodes Distance K in Binary Tree
TreeLinked List
Medium
50.0%
875Koko Eating BananasMedium
50.0%
1143Longest Common Subsequence
StringDP
Medium
50.0%
2488Count Subarrays With Median K
ArrayHeap
Hard
50.0%
3295Report Spam MessageMedium
50.0%
1209Remove All Adjacent Duplicates in String II
String
Medium
50.0%
3634Minimum Removals to Balance Array
Array
Medium
50.0%
11Container With Most WaterMedium
37.5%
153SumMedium
37.5%
20Valid Parentheses
Stack/Queue
Easy
37.5%
23Merge k Sorted ListsHard
37.5%
33Search in Rotated Sorted Array
ArrayBinary Search
Medium
37.5%
39Combination SumMedium
37.5%
41First Missing PositiveHard
37.5%
75Sort ColorsMedium
37.5%
98Validate Binary Search Tree
TreeBinary Search
Medium
37.5%
139Word BreakMedium
37.5%
221Maximal SquareMedium
37.5%
253Meeting Rooms IIMedium
37.5%
295Find Median from Data Stream
Heap
Hard
37.5%
322Coin Change
DP
Medium
37.5%
394Decode String
String
Medium
37.5%
994Rotting OrangesMedium
37.5%
1268Search Suggestions SystemMedium
37.5%
127Word LadderHard
37.5%
1315Sum of Nodes with Even-Valued Grandparent
DPLinked List
Medium
37.5%
1552Magnetic Force Between Two BallsMedium
37.5%
2231Largest Number After Digit Swaps by Parity
Math
Easy
37.5%
53Maximum Subarray
Array
Medium
37.5%
692Top K Frequent Words
Heap
Medium
37.5%
255Verify Preorder Sequence in Binary Search Tree
TreeBinary Search
Medium
37.5%
329Longest Increasing Path in a Matrix
Array
Hard
37.5%
366Find Leaves of Binary Tree
Tree
Medium
37.5%
134Gas StationMedium
37.5%
300Longest Increasing Subsequence
String
Medium
37.5%
239Sliding Window Maximum
Sliding Window
Hard
37.5%
767Reorganize String
String
Medium
37.5%
1944Number of Visible People in a Queue
Stack/QueueMath
Hard
37.5%
1004Max Consecutive Ones IIIMedium
37.5%
4Median of Two Sorted Arrays
ArrayHeap
Hard
37.5%
1335Minimum Difficulty of a Job ScheduleHard
37.5%
465Optimal Account BalancingHard
37.5%
21Merge Two Sorted ListsEasy
37.5%
894All Possible Full Binary Trees
Tree
Medium
37.5%
85Maximal RectangleHard
37.5%
545Boundary of Binary Tree
Tree
Medium
37.5%
2451Odd String Difference
String
Easy
37.5%
337House Robber IIIMedium
37.5%
992Subarrays with K Different Integers
ArrayMath
Hard
37.5%
743Network Delay Time
Graph
Medium
37.5%
332Reconstruct ItineraryHard
37.5%
268Missing Number
Math
Easy
37.5%
1219Path with Maximum GoldMedium
37.5%
355Design TwitterMedium
37.5%
1522Diameter of N-Ary Tree
Tree
Medium
37.5%
1438Longest Continuous Subarray With Absolute Diff Less Than or Equal to Limit
Array
Medium
37.5%
678Valid Parenthesis String
String
Medium
37.5%
207Course ScheduleMedium
37.5%
2603Collect Coins in a Tree
Tree
Hard
37.5%
22Generate ParenthesesMedium
37.5%
664Strange PrinterHard
37.5%
2366Minimum Replacements to Sort the Array
Array
Hard
37.5%
3893Maximum Team Size with Overlapping IntervalsMedium
37.5%
12Integer to Roman
Math
Medium
25.0%
13Roman to Integer
Math
Easy
25.0%
238Product of Array Except Self
Array
Medium
25.0%
696Count Binary Substrings
StringTree
Easy
25.0%
831Masking Personal InformationMedium
25.0%
152Maximum Product Subarray
Array
Medium
25.0%
2025Maximum Number of Ways to Partition an Array
ArrayDPMath
Hard
25.0%
2472Maximum Number of Non-overlapping Palindrome Substrings
StringTreeMath
Hard
25.0%
224Basic CalculatorHard
25.0%
973K Closest Points to OriginMedium
25.0%
636Exclusive Time of FunctionsMedium
25.0%
2515Shortest Distance to Target String in a Circular Array
ArrayString
Easy
25.0%
289Game of LifeMedium
25.0%
1046Last Stone WeightEasy
25.0%
437Path Sum IIIMedium
25.0%
135CandyHard
25.0%
2008Maximum Earnings From TaxiMedium
25.0%
1481Least Number of Unique Integers after K Removals
Math
Medium
25.0%
844Backspace String Compare
String
Easy
25.0%
353Design Snake GameMedium
25.0%
724Find Pivot IndexEasy
25.0%
535Encode and Decode TinyURLMedium
25.0%
125Valid Palindrome
String
Easy
25.0%
768Max Chunks To Make Sorted IIHard
25.0%
815Bus RoutesHard
25.0%
2345Finding the Number of Visible Mountains
Math
Medium
25.0%
1319Number of Operations to Make Network Connected
GraphMath
Medium
25.0%
703Kth Largest Element in a Stream
Heap
Easy
25.0%
652Find Duplicate Subtrees
Tree
Medium
25.0%
630Course Schedule IIIHard
25.0%
213House Robber IIMedium
25.0%
2065Maximum Path Quality of a Graph
Graph
Hard
25.0%
416Partition Equal Subset Sum
DP
Medium
25.0%
1245Tree Diameter
Tree
Medium
25.0%
2434Using a Robot to Print the Lexicographically Smallest String
StringGraph
Medium
25.0%
3170Lexicographically Minimum String After Removing Stars
StringGraph
Medium
25.0%
934Shortest BridgeMedium
25.0%
2062Count Vowel Substrings of a String
StringTree
Easy
25.0%
54Spiral Matrix
Array
Medium
25.0%
1839Longest Substring Of All Vowels in Order
StringTree
Medium
25.0%
287Find the Duplicate Number
Math
Medium
25.0%
3366Minimum Array Sum
Array
Medium
25.0%
105Construct Binary Tree from Preorder and Inorder Traversal
Tree
Medium
25.0%
312Burst BalloonsHard
25.0%
2534Time Taken to Cross the DoorHard
25.0%
658Find K Closest ElementsMedium
25.0%
518Coin Change II
DP
Medium
25.0%
451Sort Characters By FrequencyMedium
25.0%
981Time Based Key-Value StoreMedium
25.0%
987Vertical Order Traversal of a Binary Tree
Tree
Hard
25.0%
727Minimum Window Subsequence
StringSliding Window
Hard
25.0%
480Sliding Window Median
Sliding WindowHeap
Hard
25.0%
304Range Sum Query 2D - ImmutableMedium
25.0%
1962Remove Stones to Minimize the TotalMedium
25.0%
2035Partition Array Into Two Arrays to Minimize Sum Difference
ArrayDP
Hard
25.0%
2858Minimum Edge Reversals So Every Node Is Reachable
Linked List
Hard
25.0%
560Subarray Sum Equals K
Array
Medium
25.0%
84Largest Rectangle in HistogramHard
25.0%
778Swim in Rising WaterHard
25.0%
40Combination Sum IIMedium
25.0%
780Reaching PointsHard
25.0%
1344Angle Between Hands of a ClockMedium
25.0%
567Permutation in String
String
Medium
25.0%