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DifficultyTopic84 of 84
No.ProblemDifficultyFrequency
5Longest Palindromic Substring
StringTree
Medium
100.0%
198House RobberMedium
100.0%
2603Collect Coins in a Tree
Tree
Hard
100.0%
48Rotate ImageMedium
87.5%
212Word Search IIHard
87.5%
1380Lucky Numbers in a Matrix
ArrayMath
Easy
87.5%
54Spiral Matrix
Array
Medium
75.0%
2047Number of Valid Words in a Sentence
Math
Easy
75.0%
2081Sum of k-Mirror Numbers
Math
Hard
75.0%
412Fizz BuzzEasy
75.0%
2448Minimum Cost to Make Array Equal
Array
Hard
75.0%
2986Find Third TransactionMedium
75.0%
3508Implement RouterMedium
75.0%
3607Power Grid Maintenance
Math
Medium
75.0%
2Add Two Numbers
Math
Medium
62.5%
3Longest Substring Without Repeating Characters
StringTree
Medium
62.5%
20Valid Parentheses
Stack/Queue
Easy
62.5%
53Maximum Subarray
Array
Medium
62.5%
2016Maximum Difference Between Increasing ElementsEasy
62.5%
146LRU CacheMedium
62.5%
2067Number of Equal Count Substrings
StringTreeMath
Medium
62.5%
3047Find the Largest Area of Square Inside Two RectanglesMedium
62.5%
1784Check if Binary String Has at Most One Segment of Ones
String
Easy
62.5%
72Edit Distance
DP
Medium
62.5%
1443Minimum Time to Collect All Apples in a Tree
Tree
Medium
62.5%
498Diagonal TraverseMedium
62.5%
3648Minimum Sensors to Cover GridMedium
62.5%
1Two Sum
Sliding Window
Easy
50.0%
56Merge IntervalsMedium
50.0%
141Linked List Cycle
GraphLinked List
Easy
50.0%
149Max Points on a LineHard
50.0%
200Number of Islands
GraphMath
Medium
50.0%
202Happy Number
Math
Easy
50.0%
394Decode String
String
Medium
50.0%
26Remove Duplicates from Sorted Array
Array
Easy
50.0%
153SumMedium
37.5%
88Merge Sorted Array
Array
Easy
37.5%
121Best Time to Buy and Sell StockEasy
37.5%
206Reverse Linked List
Linked List
Easy
37.5%
283Move ZeroesEasy
37.5%
380Insert Delete GetRandom O(1)Medium
37.5%
647Palindromic Substrings
StringTree
Medium
37.5%
909Snakes and LaddersMedium
37.5%
1606Find Servers That Handled Most Number of Requests
Math
Hard
37.5%
2719Count of Integers
Math
Hard
37.5%
136Single Number
Math
Easy
37.5%
49Group Anagrams
String
Medium
37.5%
55Jump GameMedium
37.5%
151Reverse Words in a String
String
Medium
37.5%
128Longest Consecutive SequenceMedium
37.5%
125Valid Palindrome
String
Easy
37.5%
17Letter Combinations of a Phone Number
Math
Medium
37.5%
253Meeting Rooms IIMedium
37.5%
567Permutation in String
String
Medium
37.5%
230Kth Smallest Element in a BST
Tree
Medium
37.5%
560Subarray Sum Equals K
Array
Medium
37.5%
46PermutationsMedium
37.5%
605Can Place FlowersEasy
37.5%
197Rising TemperatureEasy
37.5%
239Sliding Window Maximum
Sliding Window
Hard
37.5%
653Two Sum IV - Input is a BST
TreeSliding Window
Easy
37.5%
25Reverse Nodes in k-Group
Linked List
Hard
37.5%
81Search in Rotated Sorted Array II
ArrayBinary Search
Medium
37.5%
33Search in Rotated Sorted Array
ArrayBinary Search
Medium
37.5%
75Sort ColorsMedium
37.5%
50Pow(x, n)
Math
Medium
37.5%
1290Convert Binary Number in a Linked List to Integer
Linked ListMath
Easy
37.5%
287Find the Duplicate Number
Math
Medium
37.5%
273Integer to English Words
Math
Hard
37.5%
486Predict the WinnerMedium
37.5%
642Design Search Autocomplete SystemHard
37.5%
236Lowest Common Ancestor of a Binary Tree
Tree
Medium
37.5%
79Word SearchMedium
37.5%
76Minimum Window Substring
StringTreeSliding Window
Hard
37.5%
1143Longest Common Subsequence
StringDP
Medium
37.5%
84Largest Rectangle in HistogramHard
37.5%
1047Remove All Adjacent Duplicates In String
String
Easy
37.5%
809Expressive WordsMedium
37.5%
207Course ScheduleMedium
37.5%
312Burst BalloonsHard
37.5%
1293Shortest Path in a Grid with Obstacles Elimination
Tree
Hard
37.5%
9Palindrome Number
StringMath
Easy
37.5%
525Contiguous Array
Array
Medium
37.5%
11Container With Most WaterMedium
37.5%