1 Zigzag Conversion String
Medium 100
0.5% 2 Minimum Absolute Difference Array Sorting
Easy 93
0.8% 3 Longest Increasing Subsequence Array Binary Search Dynamic Programming
Medium 88
0.6% 4 LRU Cache Hash Table Linked List Design Doubly-Linked List
Medium 83
0.5% 5 Count Vowel Strings in Ranges Array String Prefix Sum
Medium 83
0.7% 6 Find Words That Can Be Formed by Characters Array Hash Table String Counting
Easy 81
0.7% 7 Time Needed to Rearrange a Binary String String Dynamic Programming Simulation
Medium 79
0.5% 8 Maximum Number of Integers to Choose From a Range I Array Hash Table Binary Search Greedy Sorting
Medium 79
0.7% 9 Maximum Frequency Score of a Subarray Array Hash Table Math Stack Sliding Window
Hard 79
0.4% 10 Meeting Scheduler Array Two Pointers Sorting
Medium 79
0.6% 11 Minimum Non-Zero Product of the Array Elements Math Greedy Recursion
Medium 77
0.4% 12 Word Search Array String Backtracking Depth-First Search Matrix
Medium 77
0.5% 13 Smallest Greater Multiple Made of Two Digits Math Enumeration
Medium 77
0.5% 14 Number of Valid Move Combinations On Chessboard Array String Backtracking Simulation
Hard 77
0.5% 15 Number of Islands Array Depth-First Search Breadth-First Search Union-Find Matrix
Medium 77
0.6% 16 Count Array Pairs Divisible by K Array Hash Table Math Counting Number Theory
Hard 77
0.3% 17 Count the Number of Vowel Strings in Range Array String Counting
Easy 77
0.7% 18 Maximum Number of Integers to Choose From a Range II Array Binary Search Greedy Sorting
Medium 77
0.3% 19 Paint House III Array Dynamic Programming
Hard 77
0.6% 20 Maximum Sum Obtained of Any Permutation Array Greedy Sorting Prefix Sum
Medium 77
0.4% 21 Pythagorean Distance Nodes in a Tree Tree Breadth-First Search
Medium 77
0.6% 22 Product of Array Except Self Array Prefix Sum
Medium 74
0.7% 23 Maximal Square Array Dynamic Programming Matrix
Medium 74
0.5% 24 Coin Change Array Dynamic Programming Breadth-First Search
Medium 72
0.5% 25 Two Sum Array Hash Table
Easy 69
0.6% 26 Group Anagrams Array Hash Table String Sorting
Medium 69
0.7% 27 Merge Intervals Array Sorting
Medium 69
0.5% 28 Longest Substring Without Repeating Characters Hash Table String Sliding Window
Medium 65
0.4% 29 Search in Rotated Sorted Array Array Binary Search
Medium 65
0.5% 30 Best Time to Buy and Sell Stock Array Dynamic Programming
Easy 65
0.6% 31 Find the Smallest Divisor Given a Threshold Array Binary Search
Medium 65
0.7% 32 Find Median from Data Stream Two Pointers Design Sorting Heap (Priority Queue) Data Stream
Hard 65
0.5% 33 Last Stone Weight Array Heap (Priority Queue)
Easy 65
0.7% 34 Pairs of Songs With Total Durations Divisible by 60 Array Hash Table Counting
Medium 61
0.5% 35 House Robber Array Dynamic Programming
Medium 61
0.5% 36 Maximum Subarray Array Divide and Conquer Dynamic Programming
Medium 61
0.5% 37 Maximum Number of Events That Can Be Attended Array Greedy Sorting Heap (Priority Queue)
Medium 61
0.4% 38 Asteroid Collision Array Stack Simulation
Medium 61
0.5% 39 Top K Frequent Elements Array Hash Table Divide and Conquer Sorting Heap (Priority Queue) Bucket Sort Counting Quickselect
Medium 56
0.7% 40 Subarray Sum Equals K Array Hash Table Prefix Sum
Medium 56
0.5% 41 Random Pick with Weight Array Math Binary Search Prefix Sum Randomized
Medium 56
0.5% 42 Palindromic Substrings Two Pointers String Dynamic Programming
Medium 56
0.7% 43 Longest Consecutive Sequence Array Hash Table Union-Find
Medium 56
0.5% 44 Valid Sudoku Array Hash Table Matrix
Medium 56
0.6% 45 3Sum Smaller Array Two Pointers Binary Search Sorting
Medium 56
0.5% 46 Smallest String With Swaps Array Hash Table String Depth-First Search Breadth-First Search Union-Find Sorting
Medium 56
0.6% 47 Container With Most Water Array Two Pointers Greedy
Medium 49
0.6% 48 Valid Parentheses String Stack
Easy 49
0.4% 49 Trapping Rain Water Array Two Pointers Dynamic Programming Stack Monotonic Stack
Hard 49
0.7% 50 Count Vowel Substrings of a String Hash Table String
Easy 49
0.7% 51 Loud and Rich Array Depth-First Search Graph Theory Topological Sort
Medium 49
0.6% 52 Minimum Increment to Make Array Unique Array Greedy Sorting Counting
Medium 49
0.6% 53 Find Peak Element Array Binary Search
Medium 49
0.5% 54 Degree of an Array Array Hash Table
Easy 49
0.6% 55 Spiral Matrix Array Matrix Simulation
Medium 49
0.6% 56 Koko Eating Bananas Array Binary Search
Medium 49
0.5% 57 LFU Cache Hash Table Linked List Design Doubly-Linked List
Hard 49
0.5% 58 Reaching Points Math
Hard 49
0.3% 59 Subsets Array Backtracking Bit Manipulation
Medium 49
0.8% 60 Remove All Adjacent Duplicates in String II String Stack
Medium 49
0.6% 61 Top K Frequent Words Array Hash Table String Trie Sorting Heap (Priority Queue) Bucket Sort Counting
Medium 49
0.6% 62 Average Selling Price Database
Easy 49
0.4% 63 Median of Two Sorted Arrays Array Binary Search Divide and Conquer
Hard 40
0.5% 64 3Sum Array Two Pointers Sorting
Medium 40
0.4% 65 Find First and Last Position of Element in Sorted Array Array Binary Search
Medium 40
0.5% 66 Sort Colors Array Two Pointers Sorting
Medium 40
0.7% 67 Maximum Product Subarray Array Dynamic Programming
Medium 40
0.4% 68 Valid Anagram Hash Table String Sorting
Easy 40
0.7% 69 Minimum Replacements to Sort the Array Array Math Greedy
Hard 40
0.5% 70 Text Justification Array String Simulation
Hard 40
0.5% 71 Design Twitter Hash Table Linked List Design Heap (Priority Queue)
Medium 40
0.4% 72 Rotate Image Array Math Matrix
Medium 40
0.8% 73 Kth Largest Element in an Array Array Divide and Conquer Sorting Heap (Priority Queue) Quickselect
Medium 40
0.7% 74 Minimum Number of Removals to Make Mountain Array Array Binary Search Dynamic Programming Greedy
Hard 40
0.5% 75 Minimum Number of Swaps to Make the String Balanced Two Pointers String Stack Greedy
Medium 40
0.8% 76 Divide Players Into Teams of Equal Skill Array Hash Table Two Pointers Sorting
Medium 40
0.7% 77 First Missing Positive Array Hash Table
Hard 40
0.4% 78 Merge In Between Linked Lists Linked List
Medium 40
0.8% 79 Lexicographically Smallest Palindrome Two Pointers String Greedy
Easy 40
0.8% 80 Flatten Deeply Nested Array Medium 40
0.7% 81 Jump Game Array Dynamic Programming Greedy
Medium 40
0.4% 82 Happy Number Hash Table Math Two Pointers
Easy 40
0.6% 83 Course Schedule Depth-First Search Breadth-First Search Graph Theory Topological Sort
Medium 40
0.5% 84 Search a 2D Matrix II Array Binary Search Divide and Conquer Matrix
Medium 40
0.6% 85 Binary Tree Maximum Path Sum Dynamic Programming Tree Depth-First Search Binary Tree
Hard 40
0.4% 86 Move Zeroes Array Two Pointers
Easy 40
0.6% 87 Rotting Oranges Array Breadth-First Search Matrix
Medium 40
0.6% 88 Swap Nodes in Pairs Linked List Recursion
Medium 40
0.7% 89 Search Suggestions System Array String Binary Search Trie Sorting Heap (Priority Queue)
Medium 40
0.7% 90 Longest Substring Of All Vowels in Order String Sliding Window
Medium 40
0.5% 91 Serialize and Deserialize Binary Tree String Tree Depth-First Search Breadth-First Search Design Binary Tree
Hard 40
0.6% 92 Climbing Stairs Math Dynamic Programming Memoization
Easy 40
0.5% 93 Missing Element in Sorted Array Array Binary Search
Medium 40
0.6% 94 Fizz Buzz Math String Simulation
Easy 40
0.8% 95 Nearest Exit from Entrance in Maze Array Breadth-First Search Matrix
Medium 40
0.5% 96 Maximum Population Year Array Counting Prefix Sum
Easy 40
0.6% 97 Longest String Chain Array Hash Table Two Pointers String Dynamic Programming Sorting
Medium 40
0.6% 98 Minimum Edge Reversals So Every Node Is Reachable Dynamic Programming Depth-First Search Breadth-First Search Graph Theory
Hard 40
0.6% 99 Insert Interval Array
Medium 40
0.5% 100 Best Time to Buy and Sell Stock III Array Dynamic Programming
Hard 40
0.5% 101 Longest Palindromic Substring Two Pointers String Dynamic Programming
Medium 40
0.4% 102 First Unique Character in a String Hash Table String Queue Counting
Easy 40
0.7% 103 Combination Sum Array Backtracking
Medium 40
0.8% 104 Find the Index of the First Occurrence in a String Two Pointers String String Matching
Easy 40
0.5% 105 Non-overlapping Intervals Array Dynamic Programming Greedy Sorting
Medium 40
0.6%