1 Sort Integers by The Number of 1 Bits Array Bit Manipulation Sorting Counting
Easy 100
78.7% 2 Reaching Points Math
Hard 97
33.6% 3 Least Number of Unique Integers after K Removals Array Hash Table Greedy Sorting Counting
Medium 93
63.4% 4 Minimum Suffix Flips String Greedy
Medium 91
73.5% 5 Remove Colored Pieces if Both Neighbors are the Same Color Math String Greedy Game Theory
Medium 89
62.8% 6 Break a Palindrome String Greedy
Medium 86
51.5% 7 Minimum Absolute Difference Array Sorting
Easy 83
70.7% 8 Next Permutation Array Two Pointers
Medium 83
43.1% 9 Check Whether Two Strings are Almost Equivalent Hash Table String Counting
Easy 83
63.6% 10 Group Anagrams Array Hash Table String Sorting
Medium 78
70.9% 11 Best Time to Buy and Sell Stock Array Dynamic Programming
Easy 76
55.3% 12 Determine Color of a Chessboard Square Math String
Easy 74
79.3% 13 Minimum Swaps to Make Strings Equal Math String Greedy
Medium 74
64.7% 14 Numbers With Repeated Digits Math Dynamic Programming
Hard 74
43.5% 15 Merge Intervals Array Sorting
Medium 72
49.4% 16 Suspicious Bank Accounts Database
Medium 70
44.9% 17 Button with Longest Push Time Array
Easy 70
40.6% 18 Display Table of Food Orders in a Restaurant Array Hash Table String Sorting Ordered Set
Medium 70
75.7% 19 Check if Number Has Equal Digit Count and Digit Value Hash Table String Counting
Easy 70
72.4% 20 Maximum Number of Points From Grid Queries Array Two Pointers Breadth-First Search Union Find Sorting Heap (Priority Queue) Matrix
Hard 70
59.5% 21 Valid Parentheses String Stack
Easy 70
42.3% 22 Lexicographically Smallest String After Applying Operations String Depth-First Search Breadth-First Search Enumeration
Medium 70
65.3% 23 Rotate Image Array Math Matrix
Medium 70
77.9% 24 Lexicographically Smallest String After a Swap String Greedy
Easy 70
53.7% 25 Reverse Odd Levels of Binary Tree Tree Depth-First Search Breadth-First Search Binary Tree
Medium 70
86.6% 26 Find Resultant Array After Removing Anagrams Array Hash Table String Sorting
Easy 68
59.5% 27 Longest Palindromic Substring Two Pointers String Dynamic Programming
Medium 66
35.8% 28 Count Numbers with Unique Digits Math Dynamic Programming Backtracking
Medium 63
54.3% 29 Happy Number Hash Table Math Two Pointers
Easy 60
58.1% 30 Longest Substring Without Repeating Characters Hash Table String Sliding Window
Medium 60
36.9% 31 Climbing Stairs Math Dynamic Programming Memoization
Easy 56
53.5% 32 Maximum Product of Two Elements in an Array Array Sorting Heap (Priority Queue)
Easy 56
83.2% 33 Minimum Operations to Make All Array Elements Equal Array Binary Search Sorting Prefix Sum
Medium 51
36.9% 34 Subarray Sum Equals K Array Hash Table Prefix Sum
Medium 51
45.5% 35 Maximum Units on a Truck Array Greedy Sorting
Easy 51
74.3% 36 Two Sum Array Hash Table
Easy 51
55.8% 37 Fizz Buzz Math String Simulation
Easy 51
74.4% 38 Intersection of Two Arrays Array Hash Table Two Pointers Binary Search Sorting
Easy 51
76.5% 39 Generate Parentheses String Dynamic Programming Backtracking
Medium 51
77.1% 40 Maximum Subarray Array Divide and Conquer Dynamic Programming
Medium 51
52.1% 41 Best Time to Buy and Sell Stock II Array Dynamic Programming Greedy
Medium 51
69.5% 42 Rearrange Array to Maximize Prefix Score Array Greedy Sorting Prefix Sum
Medium 51
41.5% 43 Coin Change Array Dynamic Programming Breadth-First Search
Medium 45
46.5% 44 Non-overlapping Intervals Array Dynamic Programming Greedy Sorting
Medium 45
55.5% 45 Fibonacci Number Math Dynamic Programming Recursion Memoization
Easy 45
72.9% 46 Minimum Cost to Connect Sticks Array Greedy Heap (Priority Queue)
Medium 45
71.2% 47 Pascal's Triangle Array Dynamic Programming
Easy 45
77.0% 48 Minimum Cost to Make Array Equal Array Binary Search Greedy Sorting Prefix Sum
Hard 45
46.3% 49 LRU Cache Hash Table Linked List Design Doubly-Linked List
Medium 45
45.2% 50 Daily Temperatures Array Stack Monotonic Stack
Medium 45
67.4% 51 Binary Tree Right Side View Tree Depth-First Search Breadth-First Search Binary Tree
Medium 45
67.0% 52 Reverse Linked List Linked List Recursion
Easy 45
79.2% 53 Two Sum II - Input Array Is Sorted Array Two Pointers Binary Search
Medium 36
63.4% 54 Set Matrix Zeroes Array Hash Table Matrix
Medium 36
60.7% 55 Find Occurrences of an Element in an Array Array Hash Table
Medium 36
72.6% 56 Letter Combinations of a Phone Number Hash Table String Backtracking
Medium 36
63.9% 57 Palindrome Number Math
Easy 36
59.2% 58 Kth Largest Element in an Array Array Divide and Conquer Sorting Heap (Priority Queue) Quickselect
Medium 36
68.0% 59 Top K Frequent Elements Array Hash Table Divide and Conquer Sorting Heap (Priority Queue) Bucket Sort Counting Quickselect
Medium 36
64.6% 60 Average Time of Process per Machine Database
Easy 36
68.6% 61 Container With Most Water Array Two Pointers Greedy
Medium 36
57.8% 62 Permutations Array Backtracking
Medium 36
80.7% 63 Shuffle an Array Array Math Design Randomized
Medium 36
59.0% 64 Count Binary Substrings Two Pointers String
Easy 36
65.9% 65 Count Strictly Increasing Subarrays Array Math Dynamic Programming
Medium 36
71.3% 66 Open the Lock Array Hash Table String Breadth-First Search
Medium 36
60.7% 67 Minimum String Length After Removing Substrings String Stack Simulation
Easy 36
77.1% 68 Cherry Pickup Array Dynamic Programming Matrix
Hard 36
37.9% 69 Degree of an Array Array Hash Table
Easy 36
57.4% 70 Minimum Insertions to Balance a Parentheses String String Stack Greedy
Medium 36
53.2% 71 Search Suggestions System Array String Binary Search Trie Sorting Heap (Priority Queue)
Medium 36
65.1% 72 Find the Duplicate Number Array Two Pointers Binary Search Bit Manipulation
Medium 36
62.8% 73 Ugly Number Math
Easy 36
42.3% 74 Contains Duplicate Array Hash Table Sorting
Easy 36
63.2% 75 Sum of Subarray Ranges Array Stack Monotonic Stack
Medium 36
60.1% 76 Decode Ways String Dynamic Programming
Medium 36
36.5% 77 Combination Sum Array Backtracking
Medium 36
74.7% 78 Integer to Roman Hash Table Math String
Medium 36
68.6% 79 Spiral Matrix Array Matrix Simulation
Medium 36
53.9%