Catalog
一、依題號
1-500(45)
1. Two Sum
2. Add Two Numbers
3. Longest Substring Without Repeating Characters
4. Median of Two Sorted Array
5. Longest Palindromic Substring
6. Zigzag Conversion
7. Reverse Integer
8. String to Integer (atoi)
9. Palindrome Number
10. Regular Expression Matching
11. Container With Most Water
12. Integer to Roman
13. Roman to Integer
14. Longest Common Prefix
15. 3Sum
16. 3Sum Closet
17. Letter Combinations of a Phone Number
18. 4Sum
19. Remove Nth Node From End of List
20. Valid Parentheses
21. Merge Two Sorted Lists
22. Generate Parentheses
23. Merge k Sorted Lists
24. Swap Nodes in Pairs
25. Reverse Nodes in k-Group
53. Maximum Subarray
70. Climbing Stairs
79. Word Search
100. Same Tree
124. Binary Tree Maximum Path Sum
132. Palindrome Partitioning II
149. Max Points on a Line
151. Reverse Words in a String
198. House Robber
212. Word Search II
213. House Robber II
223. Rectangle Area
279. Perfect Squares
290. Word Pattern
300. Longest Increasing Subsequence
322. Coin Change
328. Odd Even Linked List
337. House Robber III
347. Top K Frequent Elements
374. Guess Number Higher or Lower II
433. Minimum Genetic Mutation
446. Arithmetic Slices II - Subsequence
452. Minimum Number of Arrows to Burst Balloons
501-1000(14)
520. Detect Capital
587. Erect the Fence
766. Toeplitz Matrix
790. Domino and Tromino Tiling
835. Image Overlap
841. Keys and Rooms
872. Leaf-Similar Trees
901. Online Stock Span
918. Maximum Sum Circular Subarray
926. Flip String to Monotone Increasing
931. Minimum Falling Path Sum
938. Range Sum of BST
944. Delete Columns to Make Sorted
947. Most Stones Removed with Same Row or Column
1001-1500(7)
1026. Maximum Difference Between Node and Ancestor
1047. Remove All Adjacent Duplicates In String
1143. Longest Common Subsequence
1235. Maximum Profit in Job Scheduling
1293. Shortest Path in a Grid with Obstacles Elimination
1323. Maximum 69 Number
1339. Maximum Product of Splitted Binary Tree
1501-2000(6)
1519. Number of Nodes in the Sub-Tree With the Same Label
1544. Make The String Great
1706. Where Will the Ball Fall
1834. Single-Threaded CPU
1926. Nearest Exit from Entrance in Maze
1962. Remove Stones to Minimize the Total
2001-2500(21)
2131. Longest Palindrome by Concatenating Two Letter Words
2136. Earliest Possible Day of Full Bloom
2279. Maximum Bags With Full Capacity of Rocks
2389. Longest Subsequence With Limited Sum
2460. Apply Operations to an Array
2461. Maximum Sum of Distinct Subarrays With Length K
2462. Total Cost to Hire K
2463. Minimum Total Distance Traveled
2465. Number of Distinct Averages
2466. Count Ways To Build Good Strings
2467. Most Profitable Path in a Tree
2468. Split Message Based on Limit
2469. Convert the Temperature
2470. Number of Subarrays With LCM Equal to K
2471. Minimum Number of Operations to Sort a Binary Tree by Level
2472. Maximum Number of Non-overlapping Palindrome Substrings
2485. Find the Pivot Integer
2486. Accept Characters to String to Make Subsequence
2487. Remove Nodes From Linked List
2488. Count Subarrays With Median K
2500. Delete Greatest Value in Each Row
2501-3000(5)
2501. Longest Square Streak in an Array
2520. Count the Digits That Divide a Number
2521. Distinct Prime Factors of Product of Array
2522. Partition String Into Substrings With Values at Most K
2523. Closest Prime Numbers in Range
二、依難度
Easy(24)
1. Two Sum
9. Palindrome Number
13. Roman to Integer
14. Longest Common Prefix
20. Valid Parentheses
21. Merge Two Sorted Lists
70. Climbing Stairs
100. Same Tree
374. Guess Number Higher or Lower II
520. Detect Capital
766. Toeplitz Matrix
872. Leaf-Similar Trees
938. Range Sum of BST
944. Delete Columns to Make Sorted
1047. Remove All Adjacent Duplicates In String
1323. Maximum 69 Number
1544. Make The String Great
2389. Longest Subsequence With Limited Sum
2460. Apply Operations to an Array
2465. Number of Distinct Averages
2469. Convert the Temperature
2485. Find the Pivot Integer
2500. Delete Greatest Value in Each Row
2520. Count the Digits That Divide a Number
Medium(59)
2. Add Two Numbers
3. Longest Substring Without Repeating Characters
5. Longest Palindromic Substring
6. Zigzag Conversion
7. Reverse Integer
8. String to Integer (atoi)
11. Container With Most Water
12. Integer to Roman
15. 3Sum
16. 3Sum Closet
17. Letter Combinations of a Phone Number
18. 4Sum
19. Remove Nth Node From End of List
22. Generate Parentheses
24. Swap Nodes in Pairs
53. Maximum Subarray
79. Word Search
151. Reverse Words in a String
198. House Robber
213. House Robber II
223. Rectangle Area
279. Perfect Squares
300. Longest Increasing Subsequence
322. Coin Change
328. Odd Even Linked List
337. House Robber III
347. Top K Frequent Elements
433. Minimum Genetic Mutation
452. Minimum Number of Arrows to Burst Balloons
790. Domino and Tromino Tiling
835. Image Overlap
841. Keys and Rooms
901. Online Stock Span
918. Maximum Sum Circular Subarray
926. Flip String to Monotone Increasing
931. Minimum Falling Path Sum
947. Most Stones Removed with Same Row or Column
1026. Maximum Difference Between Node and Ancestor
1143. Longest Common Subsequence
1339. Maximum Product of Splitted Binary Tree
1519. Number of Nodes in the Sub-Tree With the Same Label
1706. Where Will the Ball Fall
1834. Single-Threaded CPU
1926. Nearest Exit from Entrance in Maze
1962. Remove Stones to Minimize the Total
2131. Longest Palindrome by Concatenating Two Letter Words
2279. Maximum Bags With Full Capacity of Rocks
2461. Maximum Sum of Distinct Subarrays With Length K
2462. Total Cost to Hire K
2466. Count Ways To Build Good Strings
2467. Most Profitable Path in a Tree
2470. Number of Subarrays With LCM Equal to K
2471. Minimum Number of Operations to Sort a Binary Tree by Level
2486. Accept Characters to String to Make Subsequence
2487. Remove Nodes From Linked List
2501. Longest Square Streak in an Array
2521. Distinct Prime Factors of Product of Array
2522. Partition String Into Substrings With Values at Most K
2523. Closest Prime Numbers in Range
Hard(17)
4. Median of Two Sorted Array
10. Regular Expression Matching
23. Merge k Sorted Lists
25. Reverse Nodes in k-Group
124. Binary Tree Maximum Path Sum
132. Palindrome Partitioning II
149. Max Points on a Line
212. Word Search II
446. Arithmetic Slices II - Subsequence
587. Erect the Fence
1235. Maximum Profit in Job Scheduling
1293. Shortest Path in a Grid with Obstacles Elimination
2136. Earliest Possible Day of Full Bloom
2463. Minimum Total Distance Traveled
2468. Split Message Based on Limit
2472. Maximum Number of Non-overlapping Palindrome Substrings
2488. Count Subarrays With Median K
三、依分類
Array(43)
1. Two Sum
4. Median of Two Sorted Array
11. Container With Most Water
15. 3Sum
16. 3Sum Closet
18. 4Sum
53. Maximum Subarray
79. Word Search
149. Max Points on a Line
198. House Robber
212. Word Search II
213. House Robber II
300. Longest Increasing Subsequence
322. Coin Change
347. Top K Frequent Elements
446. Arithmetic Slices II - Subsequence
452. Minimum Number of Arrows to Burst Balloons
587. Erect the Fence
766. Toeplitz Matrix
835. Image Overlap
918. Maximum Sum Circular Subarray
931. Minimum Falling Path Sum
944. Delete Columns to Make Sorted
1235. Maximum Profit in Job Scheduling
1293. Shortest Path in a Grid with Obstacles Elimination
1706. Where Will the Ball Fall
1834. Single-Threaded CPU
1926. Nearest Exit from Entrance in Maze
1962. Remove Stones to Minimize the Total
2131. Longest Palindrome by Concatenating Two Letter Words
2136. Earliest Possible Day of Full Bloom
2279. Maximum Bags With Full Capacity of Rocks
2389. Longest Subsequence With Limited Sum
2460. Apply Operations to an Array
2461. Maximum Sum of Distinct Subarrays With Length K
2462. Total Cost to Hire K
2463. Minimum Total Distance Traveled
2465. Number of Distinct Averages
2467. Most Profitable Path in a Tree
2470. Number of Subarrays With LCM Equal to K
2488. Count Subarrays With Median K
2500. Delete Greatest Value in Each Row
2501. Longest Square Streak in an Array
Backtracking(4)
17. Letter Combinations of a Phone Number
22. Generate Parentheses
79. Word Search
212. Word Search II
Binary Search(7)
4. Median of Two Sorted Array
300. Longest Increasing Subsequence
374. Guess Number Higher or Lower II
1235. Maximum Profit in Job Scheduling
2389. Longest Subsequence With Limited Sum
2468. Split Message Based on Limit
2501. Longest Square Streak in an Array
Binary Search Tree(1)
Binary Tree(8)
100. Same Tree
124. Binary Tree Maximum Path Sum
337. House Robber III
938. Range Sum of BST
872. Leaf-Similar Trees
1026. Maximum Difference Between Node and Ancestor
1339. Maximum Product of Splitted Binary Tree
2471. Minimum Number of Operations to Sort a Binary Tree by Level
Breadth-First Search(10)
100. Same Tree
279. Perfect Squares
322. Coin Change
433. Minimum Genetic Mutation
841. Keys and Rooms
1293. Shortest Path in a Grid with Obstacles Elimination
1519. Number of Nodes in the Sub-Tree With the Same Label
1926. Nearest Exit from Entrance in Maze
2467. Most Profitable Path in a Tree
2471. Minimum Number of Operations to Sort a Binary Tree by Level
Bucket Sort(1)
Counting(3)
347. Top K Frequent Elements
1519. Number of Nodes in the Sub-Tree With the Same Label
2131. Longest Palindrome by Concatenating Two Letter Words
Data Stream(1)
Depth-First Search(12)
100. Same Tree
124. Binary Tree Maximum Path Sum
337. House Robber III
841. Keys and Rooms
872. Leaf-Similar Trees
938. Range Sum of BST
947. Most Stones Removed with Same Row or Column
1026. Maximum Difference Between Node and Ancestor
1339. Maximum Product of Splitted Binary Tree
1519. Number of Nodes in the Sub-Tree With the Same Label
1706. Where Will the Ball Fall
2467. Most Profitable Path in a Tree
Design(1)
Divide and Conquer(5)
4. Median of Two Sorted Array
23. Merge k Sorted Lists
53. Maximum Subarray
347. Top K Frequent Elements
918. Maximum Sum Circular Subarray
Dynamic Programming(25)
5. Longest Palindromic Substring
10. Regular Expression Matching
22. Generate Parentheses
53. Maximum Subarray
70. Climbing Stairs
124. Binary Tree Maximum Path Sum
132. Palindrome Partitioning II
198. House Robber
213. House Robber II
279. Perfect Squares
300. Longest Increasing Subsequence
322. Coin Change
337. House Robber III
446. Arithmetic Slices II - Subsequence
790. Domino and Tromino Tiling
918. Maximum Sum Circular Subarray
926. Flip String to Monotone Increasing
931. Minimum Falling Path Sum
1143. Longest Common Subsequence
1235. Maximum Profit in Job Scheduling
1706. Where Will the Ball Fall
2463. minimum Total Distance Traveled
2466. Count Ways To Build Good Strings
2472. Maximum Number of Non-overlapping Palindrome Substrings
2501. Longest Square Streak in an Array
Geometry(3)
149. Max Points on a Line
223. Rectangle Area
587. Erect the Fence
Graph(3)
841. Keys and Rooms
947. Most Stones Removed with Same Row or Column
2467. Most Profitable Path in a Tree
Greedy(8)
11. Container With Most Water
452. Minimum Number of Arrows to Burst Balloons
1323. Maximum 69 Number
2131. Longest Palindrome by Concatenating Two Letter Words
2136. Earliest Possible Day of Full Bloom
2279. Maximum Bags With Full Capacity of Rocks
2389. Longest Subsequence With Limited Sum
2486. Accept Characters to String to Make Subsequence
Hash Table(15)
1. Two Sum
3. Longest Substring Without Repeating Characters
12. Integer to Roman
13. Roman to Integer
17. Letter Combinations of a Phone Number
149. Max Points on a Line
290. Word Pattern
347. Top K Frequent Elements
433. Minimum Genetic Mutation
1519. Number of Nodes in the Sub-Tree With the Same Label
2131. Longest Palindrome by Concatenating Two Letter Words
2461. Maximum Sum of Distinct Subarrays With Length K
2465. Number of Distinct Averages
2488. Count Subarrays With Median K
2501. Longest Square Streak in an Array
Heap (Priority Queue)(5)
23. Merge k Sorted Lists
347. Top K Frequent Elements
1834. Single-Threaded CPU
1962. Remove Stones to Minimize the Total
2462. Total Cost to Hire K
Interactive(1)
374. Guess Number Higher or Lower II
Linked List(8)
2. Add Two Numbers
19. Remove Nth Node From End of List
21. Merge Two Sorted Lists
23. Merge k Sorted Lists
24. Swap Nodes in Pairs
25. Reverse Nodes in k-Group
328. Odd Even Linked List
2487. Remove Nodes From Linked List
Math(14)
2. Add Two Numbers
7. Reverse Integer
9. Palindrome Number
12. Integer to Roman
13. Roman to Integer
70. Climbing Stairs
149. Max Points on a Line
223. Rectangle Area
279. Perfect Squares
587. Erect the Fence
1323. Maximum 69 Number
2469. Convert the Temperature
2470. Number of Subarrays With LCM Equal to K
2485. Find the Pivot Integer
Matrix(9)
79. Word Search
212. Word Search II
766. Toeplitz Matrix
835. Image Overlap
931. Minimum Falling Path Sum
1293. Shortest Path in a Grid with Obstacles Elimination
1706. Where Will the Ball Fall
1926. Nearest Exit from Entrance in Maze
2500. Delete Greatest Value in Each Row
Memoization(1)
Merge Sort(1)
Monotonic Stack(2)
901. Online Stock Span
2487. Remove Nodes From Linked List
Monotonic Queue(1)
918. Maximum Sum Circular Subarray
Number Theory(1)
2470. Number of Subarrays With LCM Equal to K
Prefix Sum(3)
2389. Longest Subsequence With Limited Sum
2485. Find the Pivot Integer
2488. Count Subarrays With Median K
Queue(1)
918. Maximum Sum Circular Subarray
Quickselect(1)
Recursion(6)
2. Add Two Numbers
10. Regular Expression Matching
21. Merge Two Sorted Lists
24. Swap Nodes in Pairs
25. Reverse Nodes in k-Group
2487. Remove Nodes From Linked List
Simulation(3)
1706. Where Will the Ball Fall
2460. Apply Operations to an Array
2462. Total Cost to Hire K
Sliding Window(2)
3. Longest Substring Without Repeating Characters
2461. Maximum Sum of Distinct Subarrays With Length K
Sorting(14)
15. 3Sum
16. 3Sum Closet
18. 4Sum
347. Top K Frequent Elements
452. Minimum Number of Arrows to Burst Balloons
1235. Maximum Profit in Job Scheduling
1834. Single-Threaded CPU
2136. Earliest Possible Day of Full Bloom
2279. Maximum Bags With Full Capacity of Rocks
2389. Longest Subsequence With Limited Sum
2463. Minimum Total Distance Traveled
2465. Number of Distinct Averages
2500. Delete Greatest Value in Each Row
2501. Longest Square Streak in an Array
Stack(5)
20. Valid Parentheses
901. Online Stock Span
1047. Remove All Adjacent Duplicates In String
1544. Make The String Great
2487. Remove Nodes From Linked List
String(26)
3. Longest Substring Without Repeating Characters
5. Longest Palindromic Substring
6. Zigzag Conversion
8. String to Integer (atoi)
10. Regular Expression Matching
12. Integer to Roman
13. Roman to Integer
14. Longest Common Prefix
17. Letter Combinations of a Phone Number
20. Valid Parentheses
22. Generate Parentheses
132. Palindrome Partitioning II
151. Reverse Words in a String
212. Word Search II
290. Word Pattern
433. Minimum Genetic Mutation
520. Detect Capital
926. Flip String to Monotone Increasing
944. Delete Columns to Make Sorted
1047. Remove All Adjacent Duplicates In String
1143. Longest Common Subsequence
1544. Make The String Great
2131. Longest Palindrome by Concatenating Two Letter Words
2468. Split Message Based on Limit
2472. Maximum Number of Non-overlapping Palindrome Substrings
2486. Accept Characters to String to Make Subsequence
Tree(10)
100. Same Tree
124. Binary Tree Maximum Path Sum
337. House Robber III
872. Leaf-Similar Trees
938. Range Sum of BST
1026. Maximum Difference Between Node and Ancestor
1339. Maximum Product of Splitted Binary Tree
1519. Number of Nodes in the Sub-Tree With the Same Label
2467. Most Profitable Path in a Tree
2471. Minimum Number of Operations to Sort a Binary Tree by Level
Trie(1)
Two Pointer(9)
11. Container With Most Water
15. 3Sum
16. 3Sum Closet
18. 4Sum
19. Remove Nth Node From End of List
151. Reverse Words in a String
2462. Total Cost to Hire K
2465. Number of Distinct Averages
2486. Accept Characters to String to Make Subsequence