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DifficultyTopic20 of 20
No.ProblemDifficultyFrequency
1Two Sum
Sliding Window
Easy
100.0%
34Find First and Last Position of Element in Sorted Array
Array
Medium
100.0%
200Number of Islands
GraphMath
Medium
100.0%
5Longest Palindromic Substring
StringTree
Medium
87.5%
71Simplify PathMedium
87.5%
392Is Subsequence
String
Easy
87.5%
155Min Stack
Stack/Queue
Medium
87.5%
2694Event EmitterMedium
87.5%
33Search in Rotated Sorted Array
ArrayBinary Search
Medium
87.5%
394Decode String
String
Medium
87.5%
2605Form Smallest Number From Two Digit Arrays
ArrayMath
Easy
87.5%
1984Minimum Difference Between Highest and Lowest of K ScoresEasy
87.5%
2609Find the Longest Balanced Substring of a Binary String
StringTree
Easy
87.5%
19Remove Nth Node From End of List
Linked List
Medium
87.5%
3Longest Substring Without Repeating Characters
StringTree
Medium
75.0%
419Battleships in a BoardMedium
75.0%
448Find All Numbers Disappeared in an Array
ArrayMath
Easy
75.0%
125Valid Palindrome
String
Easy
75.0%
228Summary RangesEasy
75.0%
13Roman to Integer
Math
Easy
75.0%