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DifficultyTopic46 of 46
No.ProblemDifficultyFrequency
1Two Sum
Sliding Window
Easy
100.0%
3Longest Substring Without Repeating Characters
StringTree
Medium
100.0%
2033Minimum Operations to Make a Uni-Value GridMedium
100.0%
5Longest Palindromic Substring
StringTree
Medium
87.5%
20Valid Parentheses
Stack/Queue
Easy
87.5%
14Longest Common Prefix
DP
Easy
87.5%
283Move ZeroesEasy
87.5%
49Group Anagrams
String
Medium
75.0%
88Merge Sorted Array
Array
Easy
75.0%
121Best Time to Buy and Sell StockEasy
75.0%
242Valid Anagram
String
Easy
75.0%
189Rotate Array
Array
Medium
75.0%
153SumMedium
62.5%
42Trapping Rain WaterHard
62.5%
198House RobberMedium
62.5%
416Partition Equal Subset Sum
DP
Medium
62.5%
128Longest Consecutive SequenceMedium
62.5%
443String Compression
String
Medium
62.5%
344Reverse String
String
Easy
62.5%
387First Unique Character in a String
String
Easy
62.5%
56Merge IntervalsMedium
62.5%
22Generate ParenthesesMedium
62.5%
345Reverse Vowels of a String
String
Easy
62.5%
2Add Two Numbers
Math
Medium
50.0%
9Palindrome Number
StringMath
Easy
50.0%
1026Maximum Difference Between Node and Ancestor
Linked List
Medium
50.0%
7Reverse Integer
Math
Medium
50.0%
167Two Sum II - Input Array Is Sorted
ArraySliding Window
Medium
50.0%
50Pow(x, n)
Math
Medium
50.0%
182Duplicate EmailsEasy
50.0%
1907Count Salary CategoriesMedium
50.0%
43Multiply Strings
String
Medium
50.0%
53Maximum Subarray
Array
Medium
50.0%
151Reverse Words in a String
String
Medium
50.0%
62Unique PathsMedium
50.0%
72Edit Distance
DP
Medium
50.0%
13Roman to Integer
Math
Easy
50.0%
2620CounterEasy
50.0%
206Reverse Linked List
Linked List
Easy
50.0%
451Sort Characters By FrequencyMedium
50.0%
347Top K Frequent Elements
Heap
Medium
50.0%
215Kth Largest Element in an Array
ArrayHeap
Medium
50.0%
41First Missing PositiveHard
50.0%
4Median of Two Sorted Arrays
ArrayHeap
Hard
50.0%
21Merge Two Sorted ListsEasy
50.0%
146LRU CacheMedium
50.0%