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DifficultyTopic27 of 27
No.ProblemDifficultyFrequency
1Two Sum
Sliding Window
Easy
100.0%
3Longest Substring Without Repeating Characters
StringTree
Medium
100.0%
14Longest Common Prefix
DP
Easy
100.0%
49Group Anagrams
String
Medium
100.0%
56Merge IntervalsMedium
100.0%
126Word Ladder IIHard
100.0%
127Word LadderHard
100.0%
151Reverse Words in a String
String
Medium
100.0%
1126Active BusinessesMedium
100.0%
206Reverse Linked List
Linked List
Easy
100.0%
207Course ScheduleMedium
100.0%
218The Skyline ProblemHard
100.0%
242Valid Anagram
String
Easy
100.0%
347Top K Frequent Elements
Heap
Medium
100.0%
380Insert Delete GetRandom O(1)Medium
100.0%
381Insert Delete GetRandom O(1) - Duplicates allowedHard
100.0%
394Decode String
String
Medium
100.0%
1333Filter Restaurants by Vegan-Friendly, Price and DistanceMedium
100.0%
443String Compression
String
Medium
100.0%
1436Destination CityEasy
100.0%
1455Check If a Word Occurs As a Prefix of Any Word in a SentenceEasy
100.0%
564Find the Closest Palindrome
String
Hard
100.0%
599Minimum Index Sum of Two ListsEasy
100.0%
692Top K Frequent Words
Heap
Medium
100.0%
784Letter Case PermutationMedium
100.0%
2038Remove Colored Pieces if Both Neighbors are the Same ColorMedium
100.0%
2904Shortest and Lexicographically Smallest Beautiful String
StringGraph
Medium
50.0%