1 LRU Cache Hash Table Linked List Design Doubly-Linked List
Medium 100
0.5% 2 Find the Longest Equal Subarray Array Hash Table Binary Search Sliding Window
Medium 93
0.4% 3 Logger Rate Limiter Hash Table Design Data Stream
Easy 81
0.8% 4 String Compression Two Pointers String
Medium 77
0.6% 5 Longest Substring Without Repeating Characters Hash Table String Sliding Window
Medium 73
0.4% 6 Group Anagrams Array Hash Table String Sorting
Medium 68
0.7% 7 Binary Tree Level Order Traversal Tree Breadth-First Search Binary Tree
Medium 68
0.7% 8 Min Stack Stack Design
Medium 68
0.6% 9 Design HashMap Array Hash Table Linked List Design Hash Function
Easy 68
0.7% 10 Search in Rotated Sorted Array Array Binary Search
Medium 68
0.5% 11 Minimum Number of Food Buckets to Feed the Hamsters String Dynamic Programming Greedy
Medium 68
0.5% 12 Decode String String Stack Recursion
Medium 68
0.6% 13 Add Two Numbers Linked List Math Recursion
Medium 68
0.5% 14 Median of Two Sorted Arrays Array Binary Search Divide and Conquer
Hard 61
0.5% 15 Integer to Roman Hash Table Math String
Medium 61
0.7% 16 Top K Frequent Words Array Hash Table String Trie Sorting Heap (Priority Queue) Bucket Sort Counting
Medium 61
0.6% 17 Insert Delete GetRandom O(1) Array Hash Table Math Design Randomized
Medium 61
0.6% 18 Restore IP Addresses String Backtracking
Medium 61
0.6% 19 Longest Common Prefix Array String Trie
Easy 61
0.5% 20 Linked List Cycle Hash Table Linked List Two Pointers
Easy 61
0.5% 21 Subarray Sum Equals K Array Hash Table Prefix Sum
Medium 61
0.5% 22 Merge Sorted Array Array Two Pointers Sorting
Easy 61
0.6% 23 Merge Intervals Array Sorting
Medium 61
0.5% 24 Meeting Rooms Array Sorting
Easy 52
0.6% 25 Word Break Array Hash Table String Dynamic Programming Trie Memoization
Medium 52
0.5% 26 Two Sum Array Hash Table
Easy 52
0.6% 27 Merge Two Sorted Lists Linked List Recursion
Easy 52
0.7% 28 Sliding Window Maximum Array Queue Sliding Window Heap (Priority Queue) Monotonic Queue
Hard 52
0.5% 29 Basic Calculator Math String Stack Recursion
Hard 52
0.5% 30 Invert Binary Tree Tree Depth-First Search Breadth-First Search Binary Tree
Easy 52
0.8% 31 Valid Parentheses String Stack
Easy 52
0.4% 32 Basic Calculator II Math String Stack
Medium 52
0.5% 33 Multiply Strings Math String Simulation
Medium 52
0.4% 34 Path Sum Tree Depth-First Search Breadth-First Search Binary Tree
Easy 52
0.6% 35 Path Sum II Backtracking Tree Depth-First Search Binary Tree
Medium 52
0.6% 36 Advantage Shuffle Array Two Pointers Greedy Sorting
Medium 52
0.5% 37 Reconstruct Itinerary Array String Depth-First Search Graph Theory Sorting Heap (Priority Queue) Eulerian Circuit
Hard 52
0.4% 38 Reverse Linked List II Linked List
Medium 52
0.5% 39 Koko Eating Bananas Array Binary Search
Medium 52
0.5% 40 Maximum Length of a Concatenated String with Unique Characters Array String Backtracking Bit Manipulation
Medium 52
0.5% 41 Longest Palindromic Substring Two Pointers String Dynamic Programming
Medium 52
0.4% 42 Binary Tree Zigzag Level Order Traversal Tree Breadth-First Search Binary Tree
Medium 52
0.6% 43 Design Twitter Hash Table Linked List Design Heap (Priority Queue)
Medium 52
0.4% 44 Maximum Profit in Job Scheduling Array Binary Search Dynamic Programming Sorting
Hard 52
0.5% 45 Remove Zero Sum Consecutive Nodes from Linked List Hash Table Linked List
Medium 52
0.5% 46 Diameter of Binary Tree Tree Depth-First Search Binary Tree
Easy 52
0.7%