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DifficultyTopic43 of 43
No.ProblemDifficultyFrequency
1Two Sum
Sliding Window
Easy
100.0%
23Merge k Sorted ListsHard
100.0%
2388Change Null Values in a Table to the Previous ValueMedium
87.5%
20Valid Parentheses
Stack/Queue
Easy
75.0%
121Best Time to Buy and Sell StockEasy
75.0%
5Longest Palindromic Substring
StringTree
Medium
75.0%
176Second Highest SalaryMedium
75.0%
3Longest Substring Without Repeating Characters
StringTree
Medium
75.0%
9Palindrome Number
StringMath
Easy
62.5%
570Managers with at Least 5 Direct ReportsMedium
62.5%
14Longest Common Prefix
DP
Easy
62.5%
2594Minimum Time to Repair CarsMedium
62.5%
11Container With Most WaterMedium
62.5%
56Merge IntervalsMedium
62.5%
53Maximum Subarray
Array
Medium
62.5%
387First Unique Character in a String
String
Easy
62.5%
177Nth Highest SalaryMedium
62.5%
49Group Anagrams
String
Medium
62.5%
153SumMedium
62.5%
26Remove Duplicates from Sorted Array
Array
Easy
62.5%
67Add BinaryEasy
62.5%
70Climbing StairsEasy
62.5%
125Valid Palindrome
String
Easy
62.5%
72Edit Distance
DP
Medium
50.0%
322Coin Change
DP
Medium
50.0%
197Rising TemperatureEasy
50.0%
485Max Consecutive OnesEasy
50.0%
215Kth Largest Element in an Array
ArrayHeap
Medium
50.0%
183Customers Who Never OrderEasy
50.0%
13Roman to Integer
Math
Easy
50.0%
493Reverse PairsHard
50.0%
128Longest Consecutive SequenceMedium
50.0%
3703Remove K-Balanced Substrings
StringTree
Medium
50.0%
410Split Array Largest Sum
Array
Hard
50.0%
581Shortest Unsorted Continuous Subarray
Array
Medium
50.0%
189Rotate Array
Array
Medium
50.0%
242Valid Anagram
String
Easy
50.0%
402Remove K Digits
Math
Medium
50.0%
1047Remove All Adjacent Duplicates In String
String
Easy
50.0%
560Subarray Sum Equals K
Array
Medium
50.0%
31Next PermutationMedium
50.0%
345Reverse Vowels of a String
String
Easy
50.0%
313Super Ugly Number
Math
Medium
50.0%