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DifficultyTopic240 of 240
No.ProblemDifficultyFrequency
2993Friday Purchases IMedium
100.0%
1Two Sum
Sliding Window
Easy
87.5%
5Longest Palindromic Substring
StringTree
Medium
75.0%
9Palindrome Number
StringMath
Easy
75.0%
53Maximum Subarray
Array
Medium
75.0%
283Move ZeroesEasy
75.0%
3Longest Substring Without Repeating Characters
StringTree
Medium
62.5%
7Reverse Integer
Math
Medium
62.5%
11Container With Most WaterMedium
62.5%
14Longest Common Prefix
DP
Easy
62.5%
153SumMedium
62.5%
26Remove Duplicates from Sorted Array
Array
Easy
62.5%
28Find the Index of the First Occurrence in a String
String
Easy
62.5%
20Valid Parentheses
Stack/Queue
Easy
62.5%
55Jump GameMedium
62.5%
75Sort ColorsMedium
62.5%
121Best Time to Buy and Sell StockEasy
62.5%
136Single Number
Math
Easy
62.5%
169Majority ElementEasy
62.5%
176Second Highest SalaryMedium
62.5%
189Rotate Array
Array
Medium
62.5%
217Contains DuplicateEasy
62.5%
242Valid Anagram
String
Easy
62.5%
344Reverse String
String
Easy
62.5%
2423Remove Letter To Equalize FrequencyEasy
62.5%
2520Count the Digits That Divide a Number
Math
Easy
62.5%
560Subarray Sum Equals K
Array
Medium
62.5%
509Fibonacci Number
DPMath
Easy
62.5%
1800Maximum Ascending Subarray Sum
Array
Easy
62.5%
4Median of Two Sorted Arrays
ArrayHeap
Hard
62.5%
2Add Two Numbers
Math
Medium
50.0%
13Roman to Integer
Math
Easy
50.0%
184SumMedium
50.0%
34Find First and Last Position of Element in Sorted Array
Array
Medium
50.0%
42Trapping Rain WaterHard
50.0%
50Pow(x, n)
Math
Medium
50.0%
54Spiral Matrix
Array
Medium
50.0%
58Length of Last WordEasy
50.0%
62Unique PathsMedium
50.0%
66Plus OneEasy
50.0%
70Climbing StairsEasy
50.0%
69Sqrt(x)
Math
Easy
50.0%
88Merge Sorted Array
Array
Easy
50.0%
152Maximum Product Subarray
Array
Medium
50.0%
268Missing Number
Math
Easy
50.0%
67Add BinaryEasy
50.0%
387First Unique Character in a String
String
Easy
50.0%
2481Minimum Cuts to Divide a CircleEasy
50.0%
540Single Element in a Sorted Array
Array
Medium
50.0%
766Toeplitz Matrix
Array
Easy
50.0%
898Bitwise ORs of Subarrays
Array
Medium
50.0%
3065Minimum Operations to Exceed Threshold Value IEasy
50.0%
3066Minimum Operations to Exceed Threshold Value IIMedium
50.0%
1745Palindrome Partitioning IV
StringDP
Hard
50.0%
1752Check if Array Is Sorted and Rotated
ArrayBinary Search
Easy
50.0%
912Sort an Array
Array
Medium
50.0%
125Valid Palindrome
String
Easy
50.0%
35Search Insert Position
Binary Search
Easy
50.0%
805Split Array With Same Average
Array
Hard
50.0%
49Group Anagrams
String
Medium
50.0%
219Contains Duplicate IIEasy
50.0%
3417Zigzag Grid Traversal With SkipEasy
50.0%
182Duplicate EmailsEasy
50.0%
1125Smallest Sufficient TeamHard
50.0%
56Merge IntervalsMedium
50.0%
643Maximum Average Subarray I
Array
Easy
50.0%
312Burst BalloonsHard
50.0%
33Search in Rotated Sorted Array
ArrayBinary Search
Medium
50.0%
621Task SchedulerMedium
50.0%
181Employees Earning More Than Their ManagersEasy
50.0%
12Integer to Roman
Math
Medium
50.0%
21Merge Two Sorted ListsEasy
37.5%
22Generate ParenthesesMedium
37.5%
31Next PermutationMedium
37.5%
73Set Matrix Zeroes
Array
Medium
37.5%
78SubsetsMedium
37.5%
118Pascal's TriangleEasy
37.5%
122Best Time to Buy and Sell Stock IIMedium
37.5%
128Longest Consecutive SequenceMedium
37.5%
151Reverse Words in a String
String
Medium
37.5%
179Largest Number
Math
Medium
37.5%
202Happy Number
Math
Easy
37.5%
204Count Primes
Math
Medium
37.5%
206Reverse Linked List
Linked List
Easy
37.5%
239Sliding Window Maximum
Sliding Window
Hard
37.5%
412Fizz BuzzEasy
37.5%
532K-diff Pairs in an Array
Array
Medium
37.5%
584Find Customer RefereeEasy
37.5%
852Peak Index in a Mountain Array
ArrayBinary Search
Medium
37.5%
1148Article Views IEasy
37.5%
543Diameter of Binary Tree
Tree
Easy
37.5%
287Find the Duplicate Number
Math
Medium
37.5%
1757Recyclable and Low Fat ProductsEasy
37.5%
85Maximal RectangleHard
37.5%
485Max Consecutive OnesEasy
37.5%
416Partition Equal Subset Sum
DP
Medium
37.5%
1075Project Employees IEasy
37.5%
2006Count Number of Pairs With Absolute Difference K
Math
Easy
37.5%
51N-QueensHard
37.5%
45Jump Game IIMedium
37.5%
124Binary Tree Maximum Path Sum
Tree
Hard
37.5%
23Merge k Sorted ListsHard
37.5%
1480Running Sum of 1d Array
Array
Easy
37.5%
19Remove Nth Node From End of List
Linked List
Medium
37.5%
198House RobberMedium
37.5%
956Tallest BillboardHard
37.5%
263Ugly Number
Math
Easy
37.5%
628Maximum Product of Three Numbers
Math
Easy
37.5%
567Permutation in String
String
Medium
37.5%
155Min Stack
Stack/Queue
Medium
37.5%
875Koko Eating BananasMedium
37.5%
876Middle of the Linked List
Linked List
Easy
37.5%
48Rotate ImageMedium
37.5%
462Minimum Moves to Equal Array Elements II
Array
Medium
37.5%
297Serialize and Deserialize Binary Tree
Tree
Hard
37.5%
146LRU CacheMedium
37.5%
2095Delete the Middle Node of a Linked List
Linked List
Medium
37.5%
414Third Maximum Number
Math
Easy
37.5%
41First Missing PositiveHard
37.5%
2099Find Subsequence of Length K With the Largest Sum
String
Easy
37.5%
81Search in Rotated Sorted Array II
ArrayBinary Search
Medium
37.5%
1068Product Sales Analysis IEasy
37.5%
90Subsets IIMedium
37.5%
1493Longest Subarray of 1's After Deleting One Element
Array
Medium
37.5%
1518Water BottlesEasy
37.5%
17Letter Combinations of a Phone Number
Math
Medium
37.5%
496Next Greater Element IEasy
37.5%
455Assign CookiesEasy
37.5%
153Find Minimum in Rotated Sorted Array
ArrayBinary Search
Medium
37.5%
977Squares of a Sorted Array
Array
Easy
37.5%
27Remove ElementEasy
37.5%
8String to Integer (atoi)
StringMath
Medium
37.5%
516Longest Palindromic Subsequence
String
Medium
37.5%
167Two Sum II - Input Array Is Sorted
ArraySliding Window
Medium
37.5%
435Non-overlapping IntervalsMedium
37.5%
303Range Sum Query - ImmutableEasy
37.5%
83Remove Duplicates from Sorted ListEasy
37.5%
238Product of Array Except Self
Array
Medium
37.5%
46PermutationsMedium
37.5%
74Search a 2D Matrix
Array
Medium
37.5%
1581Customer Who Visited but Did Not Make Any TransactionsEasy
37.5%
300Longest Increasing Subsequence
String
Medium
37.5%
443String Compression
String
Medium
37.5%
3689Maximum Total Subarray Value I
Array
Medium
37.5%
234Palindrome Linked List
StringLinked List
Easy
37.5%
180Consecutive Numbers
Math
Medium
37.5%
84Largest Rectangle in HistogramHard
37.5%
1331Rank Transform of an Array
Array
Easy
37.5%
80Remove Duplicates from Sorted Array II
Array
Medium
25.0%
231Power of Two
Math
Easy
25.0%
577Employee BonusEasy
25.0%
704Binary Search
Binary Search
Easy
25.0%
1492The kth Factor of nMedium
25.0%
273Integer to English Words
Math
Hard
25.0%
1025Divisor GameEasy
25.0%
1512Number of Good Pairs
Math
Easy
25.0%
670Maximum SwapMedium
25.0%
229Majority Element IIMedium
25.0%
3163String Compression III
String
Medium
25.0%
2461Maximum Sum of Distinct Subarrays With Length K
Array
Medium
25.0%
141Linked List Cycle
GraphLinked List
Easy
25.0%
1368Minimum Cost to Make at Least One Valid Path in a GridHard
25.0%
1378Replace Employee ID With The Unique IdentifierEasy
25.0%
1497Check If Array Pairs Are Divisible by k
Array
Medium
25.0%
2563Count the Number of Fair Pairs
Math
Medium
25.0%
2703Return Length of Arguments PassedEasy
25.0%
1910Remove All Occurrences of a Substring
StringTree
Medium
25.0%
459Repeated Substring Pattern
StringTree
Easy
25.0%
3330Find the Original Typed String I
String
Easy
25.0%
164Maximum GapMedium
25.0%
1751Maximum Number of Events That Can Be Attended II
Math
Hard
25.0%
328Odd Even Linked List
Linked List
Medium
25.0%
109Convert Sorted List to Binary Search Tree
TreeBinary Search
Medium
25.0%
713Subarray Product Less Than K
Array
Medium
25.0%
3136Valid WordEasy
25.0%
1614Maximum Nesting Depth of the ParenthesesEasy
25.0%
142Linked List Cycle II
GraphLinked List
Medium
25.0%
495Teemo AttackingEasy
25.0%
979Distribute Coins in Binary Tree
Tree
Medium
25.0%
209Minimum Size Subarray Sum
Array
Medium
25.0%
94Binary Tree Inorder Traversal
Tree
Easy
25.0%
1015Smallest Integer Divisible by K
Math
Medium
25.0%
184Department Highest SalaryMedium
25.0%
1365How Many Numbers Are Smaller Than the Current Number
Math
Easy
25.0%
143Reorder ListMedium
25.0%
319Bulb SwitcherMedium
25.0%
10Regular Expression MatchingHard
25.0%
570Managers with at Least 5 Direct ReportsMedium
25.0%
350Intersection of Two Arrays II
Array
Easy
25.0%
994Rotting OrangesMedium
25.0%
3714Longest Balanced Substring II
StringTree
Medium
25.0%
38Count and SayMedium
25.0%
739Daily TemperaturesMedium
25.0%
405Convert a Number to Hexadecimal
Math
Easy
25.0%
523Continuous Subarray Sum
Array
Medium
25.0%
1143Longest Common Subsequence
StringDP
Medium
25.0%
566Reshape the Matrix
Array
Easy
25.0%
6Zigzag ConversionMedium
25.0%
409Longest Palindrome
String
Easy
25.0%
1823Find the Winner of the Circular GameMedium
25.0%
160Intersection of Two Linked Lists
Linked List
Easy
25.0%
127Word LadderHard
25.0%
1021Remove Outermost ParenthesesEasy
25.0%
746Min Cost Climbing StairsEasy
25.0%
2667Create Hello World FunctionEasy
25.0%
796Rotate String
String
Easy
25.0%
744Find Smallest Letter Greater Than TargetEasy
25.0%
1295Find Numbers with Even Number of Digits
Math
Easy
25.0%
163Sum ClosestMedium
25.0%
724Find Pivot IndexEasy
25.0%
347Top K Frequent Elements
Heap
Medium
25.0%
111Minimum Depth of Binary Tree
Tree
Easy
25.0%
57Insert IntervalMedium
25.0%
905Sort Array By Parity
Array
Easy
25.0%
1281Subtract the Product and Sum of Digits of an Integer
Math
Easy
25.0%
196Delete Duplicate EmailsEasy
25.0%
59Spiral Matrix II
Array
Medium
25.0%
100Same Tree
Tree
Easy
25.0%
448Find All Numbers Disappeared in an Array
ArrayMath
Easy
25.0%
525Contiguous Array
Array
Medium
25.0%
104Maximum Depth of Binary Tree
Tree
Easy
25.0%
1833Maximum Ice Cream BarsMedium
25.0%
930Binary Subarrays With Sum
Array
Medium
25.0%
175Combine Two TablesEasy
25.0%
230Kth Smallest Element in a BST
Tree
Medium
25.0%
394Decode String
String
Medium
25.0%
203Remove Linked List Elements
Linked List
Easy
25.0%
1402Reducing DishesHard
25.0%
692Top K Frequent Words
Heap
Medium
25.0%
1523Count Odd Numbers in an Interval Range
Math
Easy
25.0%
383Ransom NoteEasy
25.0%
904Fruit Into BasketsMedium
25.0%
200Number of Islands
GraphMath
Medium
25.0%
1679Max Number of K-Sum Pairs
Math
Medium
25.0%
177Nth Highest SalaryMedium
25.0%
987Vertical Order Traversal of a Binary Tree
Tree
Hard
25.0%
860Lemonade ChangeEasy
25.0%
442Find All Duplicates in an Array
Array
Medium
25.0%
1456Maximum Number of Vowels in a Substring of Given Length
StringTreeMath
Medium
25.0%
735Asteroid CollisionMedium
25.0%