1 Longest Subarray of 1's After Deleting One Element Array Dynamic Programming Sliding Window
Medium 100
0.7% 2 Summary Ranges Array
Easy 90
0.5% 3 Maximize Distance to Closest Person Array
Medium 89
0.5% 4 Longest Substring Without Repeating Characters Hash Table String Sliding Window
Medium 84
0.4% 5 Find K Closest Elements Array Two Pointers Binary Search Sliding Window Sorting Heap (Priority Queue)
Medium 83
0.5% 6 Subarray Sum Equals K Array Hash Table Prefix Sum
Medium 80
0.5% 7 String Compression Two Pointers String
Medium 79
0.6% 8 Merge Intervals Array Sorting
Medium 79
0.5% 9 Valid Palindrome II Two Pointers String Greedy
Easy 79
0.4% 10 Move Zeroes Array Two Pointers
Easy 76
0.6% 11 One Edit Distance Two Pointers String
Medium 73
0.3% 12 Isomorphic Strings Hash Table String
Easy 72
0.5% 13 Permutation in String Hash Table Two Pointers String Sliding Window
Medium 72
0.5% 14 Line Reflection Array Hash Table Math
Medium 71
0.4% 15 Two Sum Array Hash Table
Easy 70
0.6% 16 Longest Palindromic Substring Two Pointers String Dynamic Programming
Medium 70
0.4% 17 Valid Palindrome Two Pointers String
Easy 70
0.5% 18 Longest Strictly Increasing or Strictly Decreasing Subarray Array
Easy 70
0.6% 19 Find All Anagrams in a String Hash Table String Sliding Window
Medium 69
0.5% 20 Find the Prefix Common Array of Two Arrays Array Hash Table Bit Manipulation
Medium 68
0.9% 21 Number of Islands Array Depth-First Search Breadth-First Search Union-Find Matrix
Medium 67
0.6% 22 Insert Delete GetRandom O(1) Array Hash Table Math Design Randomized
Medium 67
0.6% 23 Group Anagrams Array Hash Table String Sorting
Medium 66
0.7% 24 Merge Sorted Array Array Two Pointers Sorting
Easy 65
0.6% 25 Interval List Intersections Array Two Pointers Sweep Line
Medium 63
0.7% 26 Trapping Rain Water Array Two Pointers Dynamic Programming Stack Monotonic Stack
Hard 62
0.7% 27 Squares of a Sorted Array Array Two Pointers Sorting
Easy 62
0.7% 28 Valid Parentheses String Stack
Easy 60
0.4% 29 Merge Two Sorted Lists Linked List Recursion
Easy 60
0.7% 30 Design an ATM Machine Array Greedy Design
Medium 60
0.5% 31 Is Subsequence Two Pointers String Dynamic Programming
Easy 60
0.5% 32 Find Duplicate Subtrees Hash Table Tree Depth-First Search Binary Tree
Medium 59
0.6% 33 Min Stack Stack Design
Medium 57
0.6% 34 Max Consecutive Ones III Array Binary Search Sliding Window Prefix Sum
Medium 55
0.7% 35 Binary Tree Right Side View Tree Depth-First Search Breadth-First Search Binary Tree
Medium 55
0.7% 36 Lowest Common Ancestor of a Binary Tree Tree Depth-First Search Binary Tree
Medium 55
0.7% 37 Product of Array Except Self Array Prefix Sum
Medium 55
0.7% 38 Median of Two Sorted Arrays Array Binary Search Divide and Conquer
Hard 53
0.5% 39 Container With Most Water Array Two Pointers Greedy
Medium 53
0.6% 40 Merge k Sorted Lists Linked List Divide and Conquer Heap (Priority Queue) Merge Sort
Hard 53
0.6% 41 Symmetric Tree Tree Depth-First Search Breadth-First Search Binary Tree
Easy 53
0.6% 42 LRU Cache Hash Table Linked List Design Doubly-Linked List
Medium 53
0.5% 43 Perfect Squares Math Dynamic Programming Breadth-First Search
Medium 53
0.6% 44 Reconstruct Itinerary Array String Depth-First Search Graph Theory Sorting Heap (Priority Queue) Eulerian Circuit
Hard 53
0.4% 45 Generate Parentheses String Dynamic Programming Backtracking
Medium 50
0.8% 46 Search in Rotated Sorted Array Array Binary Search
Medium 50
0.5% 47 Binary Tree Maximum Path Sum Dynamic Programming Tree Depth-First Search Binary Tree
Hard 50
0.4% 48 Longest Substring with At Most K Distinct Characters Hash Table String Sliding Window
Medium 50
0.5% 49 Design Hit Counter Array Binary Search Design Queue Data Stream
Medium 50
0.7% 50 Count Substrings Without Repeating Character Hash Table String Sliding Window
Medium 50
0.8% 51 Remove Element Array Two Pointers
Easy 47
0.6% 52 Number of Recent Calls Design Queue Data Stream
Easy 47
0.8% 53 Maximum Subarray Array Divide and Conquer Dynamic Programming
Medium 47
0.5% 54 Add Two Numbers Linked List Math Recursion
Medium 44
0.5% 55 Simplify Path String Stack
Medium 44
0.5% 56 Reverse Linked List Linked List Recursion
Easy 44
0.8% 57 Longest Repeating Character Replacement Hash Table String Sliding Window
Medium 44
0.6% 58 Destination City Array Hash Table String
Easy 44
0.8% 59 Can Place Flowers Array Greedy
Easy 44
0.3% 60 Basic Calculator II Math String Stack
Medium 44
0.5% 61 Remove Duplicates from Sorted Array Array Two Pointers
Easy 44
0.6% 62 Binary Tree Zigzag Level Order Traversal Tree Breadth-First Search Binary Tree
Medium 40
0.6% 63 Best Time to Buy and Sell Stock Array Dynamic Programming
Easy 40
0.6% 64 Longest Increasing Subsequence Array Binary Search Dynamic Programming
Medium 40
0.6% 65 Intersection of Two Arrays Array Hash Table Two Pointers Binary Search Sorting
Easy 40
0.8% 66 Max Consecutive Ones Array
Easy 40
0.7% 67 Product of Two Run-Length Encoded Arrays Array Two Pointers
Medium 40
0.6% 68 Longest Continuous Increasing Subsequence Array
Easy 40
0.5% 69 4Sum Array Two Pointers Sorting
Medium 40
0.4% 70 Minimum Window Substring Hash Table String Sliding Window
Hard 34
0.5% 71 Find Minimum in Rotated Sorted Array Array Binary Search
Medium 34
0.5% 72 Lowest Common Ancestor of a Binary Search Tree Tree Depth-First Search Binary Search Tree Binary Tree
Medium 34
0.7% 73 Intersection of Two Arrays II Array Hash Table Two Pointers Binary Search Sorting
Easy 34
0.6% 74 Continuous Subarray Sum Array Hash Table Math Prefix Sum
Medium 34
0.3% 75 Monotonic Array Array
Easy 34
0.6% 76 Range Sum of BST Tree Depth-First Search Binary Search Tree Binary Tree
Easy 34
0.9% 77 Letter Combinations of a Phone Number Hash Table String Backtracking
Medium 34
0.7% 78 Implement Queue using Stacks Stack Design Queue
Easy 34
0.7% 79 Design an Ordered Stream Array Hash Table Design Data Stream
Easy 34
0.8% 80 Remove Nth Node From End of List Linked List Two Pointers
Medium 34
0.5% 81 Binary Tree Level Order Traversal Tree Breadth-First Search Binary Tree
Medium 34
0.7% 82 Find Median from Data Stream Two Pointers Design Sorting Heap (Priority Queue) Data Stream
Hard 34
0.5% 83 Add Strings Math String Simulation
Easy 34
0.5% 84 Linked List Cycle Hash Table Linked List Two Pointers
Easy 34
0.5% 85 Matrix Diagonal Sum Array Matrix
Easy 34
0.8% 86 Sliding Window Maximum Array Queue Sliding Window Heap (Priority Queue) Monotonic Queue
Hard 34
0.5% 87 Allow One Function Call Easy 34
0.9% 88 Function Composition Easy 34
0.9% 89 Reverse Integer Math
Medium 27
0.3% 90 Validate Binary Search Tree Tree Depth-First Search Binary Search Tree Binary Tree
Medium 27
0.4% 91 Two Sum II - Input Array Is Sorted Array Two Pointers Binary Search
Medium 27
0.7% 92 Majority Element Array Hash Table Divide and Conquer Sorting Counting
Easy 27
0.7% 93 Palindrome Linked List Linked List Two Pointers Stack Recursion
Easy 27
0.6% 94 Valid Anagram Hash Table String Sorting
Easy 27
0.7% 95 First Unique Character in a String Hash Table String Queue Counting
Easy 27
0.7% 96 Longest Substring with At Least K Repeating Characters Hash Table String Divide and Conquer Sliding Window
Medium 27
0.5% 97 Jewels and Stones Hash Table String
Easy 27
0.9% 98 Text Justification Array String Simulation
Hard 27
0.5% 99 Coin Change Array Dynamic Programming Breadth-First Search
Medium 27
0.5% 100 Merge Two 2D Arrays by Summing Values Array Hash Table Two Pointers
Easy 27
0.8% 101 Implement Rand10() Using Rand7() Math Rejection Sampling Randomized Probability and Statistics
Medium 27
0.5% 102 Daily Temperatures Array Stack Monotonic Stack
Medium 27
0.7% 103 Swap Nodes in Pairs Linked List Recursion
Medium 27
0.7% 104 Lowest Common Ancestor of a Binary Tree III Hash Table Two Pointers Tree Binary Tree
Medium 27
0.8% 105 Create Hello World Function Easy 27
0.8% 106 Cinema Seat Allocation Array Hash Table Greedy Bit Manipulation
Medium 27
0.4% 107 Counter II Easy 27
0.8% 108 Search Insert Position Array Binary Search
Easy 27
0.5% 109 Path Crossing Hash Table String
Easy 27
0.6% 110 Rotting Oranges Array Breadth-First Search Matrix
Medium 27
0.6% 111 Employees Earning More Than Their Managers Database
Easy 27
0.7% 112 Maximum Average Subarray I Array Sliding Window
Easy 27
0.5% 113 Find the Difference of Two Arrays Array Hash Table
Easy 27
0.8% 114 Find Common Elements Between Two Arrays Array Hash Table
Easy 27
0.8% 115 Subarray Sums Divisible by K Array Hash Table Prefix Sum
Medium 27
0.6% 116 Minimum Size Subarray Sum Array Binary Search Sliding Window Prefix Sum
Medium 27
0.5% 117 Search a 2D Matrix Array Binary Search Matrix
Medium 27
0.5% 118 Longest Continuous Subarray With Absolute Diff Less Than or Equal to Limit Array Queue Sliding Window Heap (Priority Queue) Ordered Set Monotonic Queue
Medium 27
0.6% 119 Evaluate Reverse Polish Notation Array Math Stack
Medium 27
0.6% 120 Maximum Product of Two Elements in an Array Array Sorting Heap (Priority Queue)
Easy 27
0.8% 121 Spiral Matrix Array Matrix Simulation
Medium 27
0.6% 122 Zigzag Iterator Array Design Queue Iterator
Medium 27
0.7% 123 Binary Search Array Binary Search
Easy 27
0.6% 124 Meeting Scheduler Array Two Pointers Sorting
Medium 27
0.6% 125 Top K Frequent Elements Array Hash Table Divide and Conquer Sorting Heap (Priority Queue) Bucket Sort Counting Quickselect
Medium 27
0.7% 126 Palindrome Number Math
Easy 27
0.6% 127 Subarrays with K Different Integers Array Hash Table Sliding Window Counting
Hard 27
0.7% 128 Add Binary Math String Bit Manipulation Simulation
Easy 27
0.6%