1 Largest Number Array String Greedy Sorting
Medium 100
0.4% 2 Move Zeroes Array Two Pointers
Easy 85
0.6% 3 Reverse Nodes in Even Length Groups Linked List
Medium 85
0.6% 4 Maximum Twin Sum of a Linked List Linked List Two Pointers Stack
Medium 82
0.8% 5 Spiral Matrix Array Matrix Simulation
Medium 77
0.6% 6 Reverse Odd Levels of Binary Tree Tree Depth-First Search Breadth-First Search Binary Tree
Medium 72
0.9% 7 Find Bottom Left Tree Value Tree Depth-First Search Breadth-First Search Binary Tree
Medium 72
0.7% 8 Count Good Nodes in Binary Tree Tree Depth-First Search Breadth-First Search Binary Tree
Medium 72
0.7% 9 Delete Leaves With a Given Value Tree Depth-First Search Binary Tree
Medium 72
0.8% 10 Merge Nodes in Between Zeros Linked List Simulation
Medium 65
0.9% 11 Minimum Swaps to Group All 1's Together II Array Sliding Window
Medium 65
0.7% 12 Count Pairs Whose Sum is Less than Target Array Two Pointers Binary Search Sorting
Easy 65
0.9% 13 Reverse Nodes in k-Group Linked List Recursion
Hard 65
0.7% 14 Remove K Digits String Stack Greedy Monotonic Stack
Medium 65
0.4% 15 Daily Temperatures Array Stack Monotonic Stack
Medium 65
0.7% 16 Maximum Difference Between Node and Ancestor Tree Depth-First Search Binary Tree
Medium 65
0.8% 17 Group Anagrams Array Hash Table String Sorting
Medium 65
0.7% 18 Invert Binary Tree Tree Depth-First Search Breadth-First Search Binary Tree
Easy 65
0.8% 19 Koko Eating Bananas Array Binary Search
Medium 65
0.5% 20 Merge Two Binary Trees Tree Depth-First Search Breadth-First Search Binary Tree
Easy 65
0.8% 21 Sum of Nodes with Even-Valued Grandparent Tree Depth-First Search Breadth-First Search Binary Tree
Medium 65
0.9% 22 Merge Two Sorted Lists Linked List Recursion
Easy 65
0.7% 23 Odd Even Linked List Linked List
Medium 65
0.6% 24 Rotate List Linked List Two Pointers
Medium 65
0.4% 25 Find the Substring With Maximum Cost Array Hash Table String Dynamic Programming
Medium 56
0.6% 26 Flatten Binary Tree to Linked List Linked List Stack Tree Depth-First Search Binary Tree
Medium 56
0.7% 27 Remove Nth Node From End of List Linked List Two Pointers
Medium 56
0.5% 28 Palindrome Partitioning II String Dynamic Programming
Hard 56
0.4% 29 Search in Rotated Sorted Array Array Binary Search
Medium 56
0.5% 30 Find Largest Value in Each Tree Row Tree Depth-First Search Breadth-First Search Binary Tree
Medium 56
0.7% 31 Largest Rectangle in Histogram Array Stack Monotonic Stack
Hard 56
0.5% 32 Island Perimeter Array Depth-First Search Breadth-First Search Matrix
Easy 56
0.7% 33 Climbing Stairs Math Dynamic Programming Memoization
Easy 56
0.5% 34 Unique Email Addresses Array Hash Table String
Easy 56
0.7% 35 Binary Tree Level Order Traversal Tree Breadth-First Search Binary Tree
Medium 56
0.7%