Skip to main content
DifficultyTopic169 of 169
No.ProblemDifficultyFrequency
54Spiral Matrix
Array
Medium
100.0%
394Decode String
String
Medium
100.0%
1Two Sum
Sliding Window
Easy
87.5%
3Longest Substring Without Repeating Characters
StringTree
Medium
87.5%
5Longest Palindromic Substring
StringTree
Medium
87.5%
20Valid Parentheses
Stack/Queue
Easy
87.5%
42Trapping Rain WaterHard
87.5%
49Group Anagrams
String
Medium
87.5%
56Merge IntervalsMedium
87.5%
70Climbing StairsEasy
87.5%
121Best Time to Buy and Sell StockEasy
87.5%
6Zigzag ConversionMedium
75.0%
11Container With Most WaterMedium
75.0%
10Regular Expression MatchingHard
75.0%
22Generate ParenthesesMedium
75.0%
44Wildcard MatchingHard
75.0%
48Rotate ImageMedium
75.0%
165Compare Version Numbers
Math
Medium
75.0%
200Number of Islands
GraphMath
Medium
75.0%
2164Sort Even and Odd Indices IndependentlyEasy
75.0%
1275Find Winner on a Tic Tac Toe GameEasy
75.0%
1910Remove All Occurrences of a Substring
StringTree
Medium
75.0%
179Largest Number
Math
Medium
75.0%
69Sqrt(x)
Math
Easy
75.0%
739Daily TemperaturesMedium
75.0%
3827Count Monobit Integers
Math
Easy
75.0%
13Roman to Integer
Math
Easy
62.5%
14Longest Common Prefix
DP
Easy
62.5%
17Letter Combinations of a Phone Number
Math
Medium
62.5%
153SumMedium
62.5%
33Search in Rotated Sorted Array
ArrayBinary Search
Medium
62.5%
36Valid SudokuMedium
62.5%
53Maximum Subarray
Array
Medium
62.5%
55Jump GameMedium
62.5%
72Edit Distance
DP
Medium
62.5%
88Merge Sorted Array
Array
Easy
62.5%
238Product of Array Except Self
Array
Medium
62.5%
283Move ZeroesEasy
62.5%
435Non-overlapping IntervalsMedium
62.5%
735Asteroid CollisionMedium
62.5%
227Basic Calculator IIMedium
62.5%
32Longest Valid Parentheses
Stack/Queue
Hard
62.5%
994Rotting OrangesMedium
62.5%
560Subarray Sum Equals K
Array
Medium
62.5%
2Add Two Numbers
Math
Medium
62.5%
45Jump Game IIMedium
62.5%
463Island Perimeter
Graph
Easy
62.5%
540Single Element in a Sorted Array
Array
Medium
62.5%
3853Merge Close CharactersMedium
62.5%
1344Angle Between Hands of a ClockMedium
62.5%
9Palindrome Number
StringMath
Easy
50.0%
163Sum ClosestMedium
50.0%
26Remove Duplicates from Sorted Array
Array
Easy
50.0%
28Find the Index of the First Occurrence in a String
String
Easy
50.0%
4Median of Two Sorted Arrays
ArrayHeap
Hard
50.0%
38Count and SayMedium
50.0%
51N-QueensHard
50.0%
79Word SearchMedium
50.0%
91Decode WaysMedium
50.0%
151Reverse Words in a String
String
Medium
50.0%
171Excel Sheet Column Number
Math
Easy
50.0%
189Rotate Array
Array
Medium
50.0%
205Isomorphic Strings
String
Easy
50.0%
1299Replace Elements with Greatest Element on Right SideEasy
50.0%
416Partition Equal Subset Sum
DP
Medium
50.0%
498Diagonal TraverseMedium
50.0%
212Word Search IIHard
50.0%
37Sudoku SolverHard
50.0%
217Contains DuplicateEasy
50.0%
85Maximal RectangleHard
50.0%
166Fraction to Recurring DecimalMedium
50.0%
451Sort Characters By FrequencyMedium
50.0%
118Pascal's TriangleEasy
50.0%
169Majority ElementEasy
50.0%
125Valid Palindrome
String
Easy
50.0%
43Multiply Strings
String
Medium
50.0%
949Largest Time for Given Digits
Math
Medium
50.0%
73Set Matrix Zeroes
Array
Medium
50.0%
859Buddy Strings
String
Easy
50.0%
21Merge Two Sorted ListsEasy
50.0%
174Dungeon GameHard
50.0%
76Minimum Window Substring
StringTreeSliding Window
Hard
50.0%
215Kth Largest Element in an Array
ArrayHeap
Medium
50.0%
64Minimum Path SumMedium
50.0%
1636Sort Array by Increasing Frequency
Array
Easy
50.0%
316Remove Duplicate LettersMedium
50.0%
452Minimum Number of Arrows to Burst Balloons
Math
Medium
50.0%
347Top K Frequent Elements
Heap
Medium
50.0%
134Gas StationMedium
50.0%
1732Find the Highest AltitudeEasy
50.0%
904Fruit Into BasketsMedium
50.0%
695Max Area of Island
Graph
Medium
50.0%
168Excel Sheet Column TitleEasy
50.0%
242Valid Anagram
String
Easy
50.0%
1689Partitioning Into Minimum Number Of Deci-Binary Numbers
DPMath
Medium
50.0%
860Lemonade ChangeEasy
50.0%
12Integer to Roman
Math
Medium
37.5%
35Search Insert Position
Binary Search
Easy
37.5%
39Combination SumMedium
37.5%
59Spiral Matrix II
Array
Medium
37.5%
78SubsetsMedium
37.5%
93Restore IP AddressesMedium
37.5%
122Best Time to Buy and Sell Stock IIMedium
37.5%
128Longest Consecutive SequenceMedium
37.5%
139Word BreakMedium
37.5%
198House RobberMedium
37.5%
202Happy Number
Math
Easy
37.5%
273Integer to English Words
Math
Hard
37.5%
287Find the Duplicate Number
Math
Medium
37.5%
290Word PatternEasy
37.5%
322Coin Change
DP
Medium
37.5%
345Reverse Vowels of a String
String
Easy
37.5%
1768Merge Strings Alternately
String
Easy
37.5%
1823Find the Winner of the Circular GameMedium
37.5%
84Largest Rectangle in HistogramHard
37.5%
539Minimum Time DifferenceMedium
37.5%
829Consecutive Numbers Sum
Math
Hard
37.5%
8String to Integer (atoi)
StringMath
Medium
37.5%
518Coin Change II
DP
Medium
37.5%
488Zuma GameHard
37.5%
443String Compression
String
Medium
37.5%
916Word SubsetsMedium
37.5%
97Interleaving String
String
Medium
37.5%
2305Fair Distribution of CookiesMedium
37.5%
2133Check if Every Row and Column Contains All Numbers
Math
Easy
37.5%
1512Number of Good Pairs
Math
Easy
37.5%
349Intersection of Two Arrays
Array
Easy
37.5%
1353Maximum Number of Events That Can Be Attended
Math
Medium
37.5%
328Odd Even Linked List
Linked List
Medium
37.5%
1781Sum of Beauty of All Substrings
StringTree
Medium
37.5%
1963Minimum Number of Swaps to Make the String Balanced
StringMath
Medium
37.5%
796Rotate String
String
Easy
37.5%
54201 Matrix
Array
Medium
37.5%
767Reorganize String
String
Medium
37.5%
184SumMedium
37.5%
1108Defanging an IP AddressEasy
37.5%
494Target SumMedium
37.5%
516Longest Palindromic Subsequence
String
Medium
37.5%
925Long Pressed NameEasy
37.5%
420Strong Password CheckerHard
37.5%
149Max Points on a LineHard
37.5%
167Two Sum II - Input Array Is Sorted
ArraySliding Window
Medium
37.5%
503Next Greater Element IIMedium
37.5%
279Perfect SquaresMedium
37.5%
213House Robber IIMedium
37.5%
219Contains Duplicate IIEasy
37.5%
1394Find Lucky Integer in an Array
ArrayMath
Easy
37.5%
40Combination Sum IIMedium
37.5%
387First Unique Character in a String
String
Easy
37.5%
961N-Repeated Element in Size 2N Array
Array
Easy
37.5%
392Is Subsequence
String
Easy
37.5%
239Sliding Window Maximum
Sliding Window
Hard
37.5%
455Assign CookiesEasy
37.5%
2965Find Missing and Repeated ValuesEasy
37.5%
557Reverse Words in a String III
String
Easy
37.5%
115Distinct Subsequences
String
Hard
37.5%
62Unique PathsMedium
37.5%
146LRU CacheMedium
37.5%
747Largest Number At Least Twice of Others
Math
Easy
37.5%
66Plus OneEasy
37.5%
268Missing Number
Math
Easy
37.5%
34Find First and Last Position of Element in Sorted Array
Array
Medium
37.5%
402Remove K Digits
Math
Medium
37.5%
2114Maximum Number of Words Found in Sentences
Math
Easy
37.5%
207Course ScheduleMedium
37.5%
1185Day of the WeekEasy
37.5%
41First Missing PositiveHard
37.5%
875Koko Eating BananasMedium
37.5%
263Ugly Number
Math
Easy
37.5%