- Sequence DP (4)
- MiniMax (1)
- Two Pointers (15)
- String (19)
- Math (12)
- DP (47)
- BFS (11)
- Segment Tree (1)
- Design (8)
- DFS (27)
- Game Theory (3)
- Hash Table (16)
- Backtracking (9)
- Bit Manipulation (7)
- Divide and Conquer (5)
- Status DP (1)
- Topological Sort (4)
- Sort (6)
- Tree (20)
- Greedy (6)
- Trie (6)
- Coordinate DP (3)
- BST (16)
- Binary Tree (2)
- Binary Search (23)
- Heap (6)
- Interval DP (1)
- Stack (12)
- Linked List (7)
- Array (44)
- Binary Indexed Tree (1)
- Graph (5)
- Union Find (7)
- Memoization (5)
- Sweep Line (4)
- Two Stacks (1)
- Interval (1)
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Longest Increasing Subsequence.java | Medium | Java | [Binary Search, DP, Memoization, Sequence DP] | |
1 | House Robber.java | Easy | Java | [DP, Sequence DP] | |
2 | House Robber II.java | Medium | Java | [DP, Sequence DP] | |
3 | Climbing Stairs.java | Easy | Java | [DP, Memoization, Sequence DP] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Burst Balloons.java | Hard | Java | [DP, Divide and Conquer, Memoization, Range DP] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Coins in a Line II.java | Medium | Java | [Array, DP, Game Theory, Memoization, MiniMax] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Reverse Vowels of a String.java | Easy | Java | [String, Two Pointers] | |
1 | 2 Sum II - Input array is sorted.java | Medium | Java | [Array, Binary Search, Two Pointers] | |
2 | 2 Sum II.java | Medium | Java | [Array, Binary Search, Two Pointers] | |
3 | 3 Sum Closest.java | Medium | Java | [Array, Two Pointers] | |
4 | 3 Sum.java | Medium | Java | [Array, Two Pointers] | |
5 | 3 Sum Smaller.java | Medium | Java | [Array, Two Pointers] | |
6 | Intersection of Two Arrays II.java | Easy | Java | [Binary Search, Hash Table, Sort, Two Pointers] | |
7 | Minimum Size Subarray Sum.java | Medium | Java | [Array, Binary Search, Two Pointers] | |
8 | Longest Substring Without Repeating Characters.java | Medium | Java | [Hash Table, String, Two Pointers] | |
9 | Minimum Window Substring.java | Hard | Java | [Hash Table, String, Two Pointers] | |
10 | Linked List Cycle.java | Easy | Java | [Linked List, Two Pointers] | |
11 | Remove Nth Node From End of List.java | Medium | Java | [Linked List, Two Pointers] | |
12 | Linked List Cycle II.java | Medium | Java | [Linked List, Two Pointers] | |
13 | Trapping Rain Water.java | Hard | Java | [Array, Stack, Two Pointers] | |
14 | Find the Duplicate Number.java | Medium | Java | [Array, Binary Search, Two Pointers] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Judge Route Circle.java | Easy | Java | [String] | |
1 | First Unique Character in a String.java | Easy | Java | [Hash Table, String] | |
2 | Reverse Vowels of a String.java | Easy | Java | [String, Two Pointers] | |
3 | Decode Ways.java | Review | Java | [DP, String] | |
4 | Scramble String.java | Hard | Java | [DP, String] | |
5 | Interleaving String.java | Hard | Java | [DP, String] | |
6 | Letter Combinations of a Phone Number.java | Medium | Java | [Backtracking, String] | |
7 | Edit Distance.java | Hard | Java | [DP, String] | |
8 | Distinct Subsequences.java | Hard | Java | [DP, String] | |
9 | Regular Expression Matching.java | Review | Java | [Backtracking, DP, String] | |
10 | Wildcard Matching.java | Hard | Java | [Backtracking, DP, Greedy, String] | |
11 | Add Binary.java | Easy | Java | [Math, String] | |
12 | Longest Substring Without Repeating Characters.java | Medium | Java | [Hash Table, String, Two Pointers] | |
13 | Minimum Window Substring.java | Hard | Java | [Hash Table, String, Two Pointers] | |
14 | Longest Substring with At Most K Distinct Characters.java | Medium | Java | [Hash Table, String] | |
15 | Palindrome Pairs.java | Hard | Java | [Hash Table, String, Trie] | |
16 | Change to Anagram.java | Easy | Java | [String] | |
17 | Compare Version Numbers.java | Medium | Java | [String] | |
18 | Compare Strings.java | Easy | Java | [String] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Power of Three.java | Easy | Java | [Math] | |
1 | Plus One.java | Easy | Java | [Array, Math] | |
2 | Power of Two.java | Easy | Java | [Bit Manipulation, Math] | |
3 | Encode and Decode TinyURL.java | Medium | Java | [Hash Table, Math] | |
4 | Perfect Squares.java | Medium | Java | [BFS, DP, Math] | |
5 | Valid Perfect Square.java | Review | Java | [Binary Search, Math] | |
6 | Pow(x,n).java | Medium | Java | [Binary Search, Math] | |
7 | Add Binary.java | Easy | Java | [Math, String] | |
8 | Add Digits.java | Easy | Java | [Math] | |
9 | Add Two Numbers.java | Medium | Java | [Linked List, Math] | |
10 | Reverse Integer.java | Easy | Java | [Math] | |
11 | Sqrt(x).java | Easy | Java | [Binary Search, Math] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Coin Change.java | Medium | Java | [DP] | |
1 | Maximum Product Subarray.java | Medium | Java | [Array, DP] | |
2 | k Sum.java | Hard | Java | [DP] | |
3 | Longest Continuous Increasing Subsequence.java | Easy | Java | [Array, DP] | |
4 | Longest Increasing Subsequence.java | Medium | Java | [Binary Search, DP, Memoization, Sequence DP] | |
5 | Unique Binary Search Tree.java | Medium | Java | [BST, DP, Tree] | |
6 | Unique Paths II.java | Medium | Java | [Array, DP] | |
7 | Counting Bits.java | Medium | Java | [Bit Manipulation, DP] | |
8 | Bomb Enemy.java | Medium | Java | [DP] | |
9 | Paint House.java | Easy | Java | [DP] | |
10 | Decode Ways.java | Review | Java | [DP, String] | |
11 | House Robber.java | Easy | Java | [DP, Sequence DP] | |
12 | House Robber II.java | Medium | Java | [DP, Sequence DP] | |
13 | Best Time to Buy and Sell Stock I.java | Easy | Java | [Array, DP] | |
14 | Best Time to Buy and Sell Stock III .java | Hard | Java | [Array, DP] | |
15 | Best Time to Buy and Sell Stock IV.java | Hard | Java | [DP] | |
16 | Paint House II.java | Review | Java | [DP] | |
17 | Backpack.java | Medium | Java | [DP] | |
18 | Perfect Squares.java | Medium | Java | [BFS, DP, Math] | |
19 | Palindrome Partitioning II.java | Hard | Java | [DP] | |
20 | Backpack V.java | Medium | Java | [DP] | |
21 | Backpack VI.java | Medium | Java | [DP] | |
22 | Copy Books.java | Hard | Java | [Binary Search, DP] | |
23 | Backpack II.java | Medium | Java | [DP] | |
24 | Backpack III.java | Review | Java | [DP] | |
25 | Longest Palindromic Subsequence.java | Medium | Java | [DP] | |
26 | Scramble String.java | Hard | Java | [DP, String] | |
27 | Best Time to Buy and Sell Stock with Cooldown.java | Medium | Java | [DP] | |
28 | Longest Common Subsequence.java | Medium | Java | [DP] | |
29 | Interleaving String.java | Hard | Java | [DP, String] | |
30 | Edit Distance.java | Hard | Java | [DP, String] | |
31 | Distinct Subsequences.java | Hard | Java | [DP, String] | |
32 | Regular Expression Matching.java | Review | Java | [Backtracking, DP, String] | |
33 | Wildcard Matching.java | Hard | Java | [Backtracking, DP, Greedy, String] | |
34 | Ones and Zeroes.java | Hard | Java | [DP] | |
35 | Word Break II.java | Review | Java | [Backtracking, DP] | |
36 | Unique Path.java | Medium | Java | [Array, Coordinate DP, DP] | |
37 | Maximal Rectangle.java | Hard | Java | [Array, DP, Hash Table, Stack] | |
38 | Maximal Square.java | Medium | Java | [Coordinate DP, DP] | |
39 | Minimum Path Sum.java | Medium | Java | [Array, Coordinate DP, DP] | |
40 | House Robber III.java | Hard | Java | [DFS, DP, Status DP, Tree] | |
41 | Longest Increasing Path in a Matrix.java | Hard | Java | [DFS, DP, Memoization, Topological Sort] | |
42 | Coins in a Line.java | Medium | Java | [DP, Game Theory, Greedy] | |
43 | Coins in a Line II.java | Medium | Java | [Array, DP, Game Theory, Memoization, MiniMax] | |
44 | Climbing Stairs.java | Easy | Java | [DP, Memoization, Sequence DP] | |
45 | Coins in a Line III.java | Hard | Java | [Array, DP, Game Theory, Interval DP, Memoization] | |
46 | Burst Balloons.java | Hard | Java | [DP, Divide and Conquer, Memoization, Range DP] | |
47 | Nim Game.java | Easy | Java | [Brainteaser, DP, Game Theory] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Perfect Squares.java | Medium | Java | [BFS, DP, Math] | |
1 | Clone Graph.java | Medium | Java | [BFS, DFS, Graph] | |
2 | Number of Islands.java | Medium | Java | [BFS, DFS, Union Find] | |
3 | Graph Valid Tree.java | Medium | Java | [BFS, DFS, Graph, Union Find] | |
4 | Surrounded Regions.java | Review | Java | [BFS, DFS, Union Find] | |
5 | Trapping Rain Water II.java | Hard | Java | [BFS, Heap] | |
6 | Course Schedule.java | Medium | Java | [BFS, DFS, Graph, Topological Sort] | |
7 | Course Schedule II.java | Medium | Java | [BFS, DFS, Graph, Topological Sort] | |
8 | Alien Dictionary.java | Hard | Java | [BFS, Backtracking, DFS, Graph, Topological Sort] | |
9 | Binary Tree Preorder Traversal.java | Easy | Java | [BFS, DFS, Stack, Tree] | |
10 | Complete Binary Tree.java | Easy | Java | [BFS, DFS, Tree] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Building Outline.java | Review | Java | [Binary Indexed Tree, Divide and Conquer, Heap, Segment Tree, Sweep Line] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Binary Search Tree Iterator.java | Medium | Java | [BST, Design, Stack, Tree] | |
1 | Flatten Nested List Iterator.java | Medium | Java | [Design, Stack] | |
2 | Implement Trie.java | Medium | Java | [Design, Trie] | |
3 | Add and Search Word.java | Medium | Java | [Backtracking, Design, Trie] | |
4 | Data Stream Median.java | Hard | Java | [Design, Heap] | |
5 | Sliding Window Median.java | Hard | Java | [Design, Heap] | |
6 | Min Stack.java | Easy | Java | [Design, Stack] | |
7 | Implement Queue using Stacks.java | Easy | Java | [Design, Stack] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Nested List Weight Sum.java | Easy | Java | [DFS] | |
1 | Same Tree.java | Easy | Java | [DFS, Tree] | |
2 | Convert Sorted Array to Binary Search Tree.java | Easy | Java | [DFS, Tree] | |
3 | Binary Tree Maximum Path Sum.java | Review | Java | [DFS, Tree] | |
4 | Construct Binary Tree from Inorder and Preorder Traversal.java | Medium | Java | [Array, DFS, Tree] | |
5 | Path Sum.java | Easy | Java | [DFS, Tree] | |
6 | Balanced Binary Tree.java | Medium | Java | [DFS, Tree] | |
7 | Populating Next Right Pointers in Each Node.java | Medium | Java | [DFS, Tree] | |
8 | Validate Binary Search Tree.java | Medium | Java | [BST, DFS, Tree] | |
9 | Convert Sorted List to Binary Search Tree.java | Medium | Java | [DFS, Linked List] | |
10 | Flatten Binary Tree to Linked List.java | Medium | Java | [Binary Tree, DFS] | |
11 | Binary Tree Paths.java | Easy | Java | [Binary Tree, DFS] | |
12 | Clone Graph.java | Medium | Java | [BFS, DFS, Graph] | |
13 | Number of Islands.java | Medium | Java | [BFS, DFS, Union Find] | |
14 | Graph Valid Tree.java | Medium | Java | [BFS, DFS, Graph, Union Find] | |
15 | Surrounded Regions.java | Review | Java | [BFS, DFS, Union Find] | |
16 | Word Search II.java | Hard | Java | [Backtracking, DFS, Trie] | |
17 | Expression Expand.java | Medium | Java | [DFS, Divide and Conquer, Stack] | |
18 | Find Peak Element II.java | Hard | Java | [Binary Search, DFS, Divide and Conquer] | |
19 | House Robber III.java | Hard | Java | [DFS, DP, Status DP, Tree] | |
20 | Longest Increasing Path in a Matrix.java | Hard | Java | [DFS, DP, Memoization, Topological Sort] | |
21 | Path Sum II.java | Easy | Java | [DFS, Tree] | |
22 | Course Schedule.java | Medium | Java | [BFS, DFS, Graph, Topological Sort] | |
23 | Course Schedule II.java | Medium | Java | [BFS, DFS, Graph, Topological Sort] | |
24 | Alien Dictionary.java | Hard | Java | [BFS, Backtracking, DFS, Graph, Topological Sort] | |
25 | Binary Tree Preorder Traversal.java | Easy | Java | [BFS, DFS, Stack, Tree] | |
26 | Complete Binary Tree.java | Easy | Java | [BFS, DFS, Tree] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Coins in a Line.java | Medium | Java | [DP, Game Theory, Greedy] | |
1 | Coins in a Line II.java | Medium | Java | [Array, DP, Game Theory, Memoization, MiniMax] | |
2 | Coins in a Line III.java | Hard | Java | [Array, DP, Game Theory, Interval DP, Memoization] | |
3 | Nim Game.java | Easy | Java | [Brainteaser, DP, Game Theory] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Find Anagram Mappings.java | Easy | Java | [Hash Table] | |
1 | Island Perimeter.java | Easy | Java | [Hash Table] | |
2 | First Unique Character in a String.java | Easy | Java | [Hash Table, String] | |
3 | Encode and Decode TinyURL.java | Medium | Java | [Hash Table, Math] | |
4 | 2 Sum.java | Easy | Java | [Array, Hash Table] | |
5 | 4 Sum.java | Medium | Java | [Hash Table] | |
6 | Intersection of Two Arrays II.java | Easy | Java | [Binary Search, Hash Table, Sort, Two Pointers] | |
7 | Valid Anagram.java | Easy | Java | [Hash Table, Sort] | |
8 | Longest Substring Without Repeating Characters.java | Medium | Java | [Hash Table, String, Two Pointers] | |
9 | Minimum Window Substring.java | Hard | Java | [Hash Table, String, Two Pointers] | |
10 | Longest Substring with At Most K Distinct Characters.java | Medium | Java | [Hash Table, String] | |
11 | Palindrome Pairs.java | Hard | Java | [Hash Table, String, Trie] | |
12 | Maximal Rectangle.java | Hard | Java | [Array, DP, Hash Table, Stack] | |
13 | Binary Tree Inorder Traversal.java | Easy | Java | [Hash Table, Stack, Tree] | |
14 | Contains Duplicate.java | Easy | Java | [Array, Hash Table] | |
15 | Contains Duplicate II.java | Easy | Java | [Array, Hash Table] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Letter Combinations of a Phone Number.java | Medium | Java | [Backtracking, String] | |
1 | Regular Expression Matching.java | Review | Java | [Backtracking, DP, String] | |
2 | Wildcard Matching.java | Hard | Java | [Backtracking, DP, Greedy, String] | |
3 | Word Break II.java | Review | Java | [Backtracking, DP] | |
4 | Add and Search Word.java | Medium | Java | [Backtracking, Design, Trie] | |
5 | Word Search II.java | Hard | Java | [Backtracking, DFS, Trie] | |
6 | Word Search.java | Medium | Java | [Array, Backtracking] | |
7 | Word Squares.java | Hard | Java | [Backtracking, Trie] | |
8 | Alien Dictionary.java | Hard | Java | [BFS, Backtracking, DFS, Graph, Topological Sort] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Power of Two.java | Easy | Java | [Bit Manipulation, Math] | |
1 | Counting Bits.java | Medium | Java | [Bit Manipulation, DP] | |
2 | Sum of Two Integers.java | Easy | Java | [Bit Manipulation] | |
3 | Swap Bits.java | Easy | Java | [Bit Manipulation] | |
4 | Update Bits.java | Medium | Java | [Bit Manipulation] | |
5 | Maximum XOR of Two Numbers in an Array.java | Medium | Java | [Bit Manipulation, Trie] | |
6 | Majority Element.java | Easy | Java | [Array, Bit Manipulation, Divide and Conquer] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Majority Element.java | Easy | Java | [Array, Bit Manipulation, Divide and Conquer] | |
1 | Expression Expand.java | Medium | Java | [DFS, Divide and Conquer, Stack] | |
2 | Find Peak Element II.java | Hard | Java | [Binary Search, DFS, Divide and Conquer] | |
3 | Building Outline.java | Review | Java | [Binary Indexed Tree, Divide and Conquer, Heap, Segment Tree, Sweep Line] | |
4 | Burst Balloons.java | Hard | Java | [DP, Divide and Conquer, Memoization, Range DP] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | House Robber III.java | Hard | Java | [DFS, DP, Status DP, Tree] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Longest Increasing Path in a Matrix.java | Hard | Java | [DFS, DP, Memoization, Topological Sort] | |
1 | Course Schedule.java | Medium | Java | [BFS, DFS, Graph, Topological Sort] | |
2 | Course Schedule II.java | Medium | Java | [BFS, DFS, Graph, Topological Sort] | |
3 | Alien Dictionary.java | Hard | Java | [BFS, Backtracking, DFS, Graph, Topological Sort] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Wiggle Sort.java | Medium | Java | [Array, Sort] | |
1 | Intersection of Two Arrays II.java | Easy | Java | [Binary Search, Hash Table, Sort, Two Pointers] | |
2 | Valid Anagram.java | Easy | Java | [Hash Table, Sort] | |
3 | Meeting Rooms.java | Easy | Java | [Sort, Sweep Line] | |
4 | Number of Airplane in the sky.java | Medium | Java | [Array, Interval, Sort, Sweep Line] | |
5 | Meeting Rooms II.java | Medium | Java | [Greedy, Heap, Sort, Sweep Line] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Unique Binary Search Tree.java | Medium | Java | [BST, DP, Tree] | |
1 | Trim a Binary Search Tree.java | Easy | Java | [BST, Tree] | |
2 | Binary Search Tree Iterator.java | Medium | Java | [BST, Design, Stack, Tree] | |
3 | Same Tree.java | Easy | Java | [DFS, Tree] | |
4 | Convert Sorted Array to Binary Search Tree.java | Easy | Java | [DFS, Tree] | |
5 | Binary Tree Maximum Path Sum.java | Review | Java | [DFS, Tree] | |
6 | Construct Binary Tree from Inorder and Preorder Traversal.java | Medium | Java | [Array, DFS, Tree] | |
7 | Path Sum.java | Easy | Java | [DFS, Tree] | |
8 | Balanced Binary Tree.java | Medium | Java | [DFS, Tree] | |
9 | Populating Next Right Pointers in Each Node.java | Medium | Java | [DFS, Tree] | |
10 | Validate Binary Search Tree.java | Medium | Java | [BST, DFS, Tree] | |
11 | Max Tree.java | Medium | Java | [Stack, Tree] | |
12 | House Robber III.java | Hard | Java | [DFS, DP, Status DP, Tree] | |
13 | Binary Tree Inorder Traversal.java | Easy | Java | [Hash Table, Stack, Tree] | |
14 | Path Sum II.java | Easy | Java | [DFS, Tree] | |
15 | Binary Tree Postorder Traversal.java | Medium | Java | [Stack, Tree, Two Stacks] | |
16 | Closest Binary Search Tree Value.java | Easy | Java | [BST, Binary Search, Tree] | |
17 | Count Complete Tree Nodes.java | Medium | Java | [Binary Search, Tree] | |
18 | Binary Tree Preorder Traversal.java | Easy | Java | [BFS, DFS, Stack, Tree] | |
19 | Complete Binary Tree.java | Easy | Java | [BFS, DFS, Tree] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Queue Reconstruction by Height.java | Medium | Java | [Greedy] | |
1 | Jump Game.java | Medium | Java | [Array, Greedy] | |
2 | Best Time to Buy and Sell Stock II.java | Easy | Java | [Array, Greedy] | |
3 | Wildcard Matching.java | Hard | Java | [Backtracking, DP, Greedy, String] | |
4 | Meeting Rooms II.java | Medium | Java | [Greedy, Heap, Sort, Sweep Line] | |
5 | Coins in a Line.java | Medium | Java | [DP, Game Theory, Greedy] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Maximum XOR of Two Numbers in an Array.java | Medium | Java | [Bit Manipulation, Trie] | |
1 | Implement Trie.java | Medium | Java | [Design, Trie] | |
2 | Add and Search Word.java | Medium | Java | [Backtracking, Design, Trie] | |
3 | Word Search II.java | Hard | Java | [Backtracking, DFS, Trie] | |
4 | Word Squares.java | Hard | Java | [Backtracking, Trie] | |
5 | Palindrome Pairs.java | Hard | Java | [Hash Table, String, Trie] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Largest Rectangle in Histogram.java | Hard | Java | [Array, Monotonous Stack, Stack] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Unique Path.java | Medium | Java | [Array, Coordinate DP, DP] | |
1 | Maximal Square.java | Medium | Java | [Coordinate DP, DP] | |
2 | Minimum Path Sum.java | Medium | Java | [Array, Coordinate DP, DP] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Flatten Binary Tree to Linked List.java | Medium | Java | [Binary Tree, DFS] | |
1 | Binary Tree Paths.java | Easy | Java | [Binary Tree, DFS] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Guess Number Higher or Lower.java | Easy | Java | [Binary Search] | |
1 | 2 Sum II - Input array is sorted.java | Medium | Java | [Array, Binary Search, Two Pointers] | |
2 | 2 Sum II.java | Medium | Java | [Array, Binary Search, Two Pointers] | |
3 | Longest Increasing Subsequence.java | Medium | Java | [Binary Search, DP, Memoization, Sequence DP] | |
4 | Copy Books.java | Hard | Java | [Binary Search, DP] | |
5 | Valid Perfect Square.java | Review | Java | [Binary Search, Math] | |
6 | Intersection of Two Arrays II.java | Easy | Java | [Binary Search, Hash Table, Sort, Two Pointers] | |
7 | Find Peak Element.java | Medium | Java | [Array, Binary Search] | |
8 | Pow(x,n).java | Medium | Java | [Binary Search, Math] | |
9 | Minimum Size Subarray Sum.java | Medium | Java | [Array, Binary Search, Two Pointers] | |
10 | Kth Smallest Number in Sorted Matrix.java | Medium | Java | [Binary Search, Heap] | |
11 | Find Minimum in Rotated Sorted Array.java | Medium | Java | [Array, Binary Search] | |
12 | Find Minimum in Rotated Sorted Array II.java | Hard | Java | [Array, Binary Search] | |
13 | Find Peak Element II.java | Hard | Java | [Binary Search, DFS, Divide and Conquer] | |
14 | Sqrt(x).java | Easy | Java | [Binary Search, Math] | |
15 | First Bad Version.java | Easy | Java | [Binary Search] | |
16 | Wood Cut.java | Medium | Java | [Binary Search] | |
17 | Find the Duplicate Number.java | Medium | Java | [Array, Binary Search, Two Pointers] | |
18 | Maximum Average Subarray II.java | Review | Java | [Array, Binary Search] | |
19 | Classical Binary Search.java | Easy | Java | [Binary Search] | |
20 | Closest Binary Search Tree Value.java | Easy | Java | [BST, Binary Search, Tree] | |
21 | Count Complete Tree Nodes.java | Medium | Java | [Binary Search, Tree] | |
22 | Closest Number in Sorted Array.java | Easy | Java | [Binary Search] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Kth Smallest Number in Sorted Matrix.java | Medium | Java | [Binary Search, Heap] | |
1 | Trapping Rain Water II.java | Hard | Java | [BFS, Heap] | |
2 | Data Stream Median.java | Hard | Java | [Design, Heap] | |
3 | Sliding Window Median.java | Hard | Java | [Design, Heap] | |
4 | Meeting Rooms II.java | Medium | Java | [Greedy, Heap, Sort, Sweep Line] | |
5 | Building Outline.java | Review | Java | [Binary Indexed Tree, Divide and Conquer, Heap, Segment Tree, Sweep Line] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Coins in a Line III.java | Hard | Java | [Array, DP, Game Theory, Interval DP, Memoization] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Binary Search Tree Iterator.java | Medium | Java | [BST, Design, Stack, Tree] | |
1 | Flatten Nested List Iterator.java | Medium | Java | [Design, Stack] | |
2 | Trapping Rain Water.java | Hard | Java | [Array, Stack, Two Pointers] | |
3 | Min Stack.java | Easy | Java | [Design, Stack] | |
4 | Implement Queue using Stacks.java | Easy | Java | [Design, Stack] | |
5 | Expression Expand.java | Medium | Java | [DFS, Divide and Conquer, Stack] | |
6 | Largest Rectangle in Histogram.java | Hard | Java | [Array, Monotonous Stack, Stack] | |
7 | Max Tree.java | Medium | Java | [Stack, Tree] | |
8 | Maximal Rectangle.java | Hard | Java | [Array, DP, Hash Table, Stack] | |
9 | Binary Tree Inorder Traversal.java | Easy | Java | [Hash Table, Stack, Tree] | |
10 | Binary Tree Postorder Traversal.java | Medium | Java | [Stack, Tree, Two Stacks] | |
11 | Binary Tree Preorder Traversal.java | Easy | Java | [BFS, DFS, Stack, Tree] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Add Two Numbers.java | Medium | Java | [Linked List, Math] | |
1 | Add Two Numbers II.java | Medium | Java | [Linked List] | |
2 | Convert Sorted List to Binary Search Tree.java | Medium | Java | [DFS, Linked List] | |
3 | Linked List Cycle.java | Easy | Java | [Linked List, Two Pointers] | |
4 | Remove Nth Node From End of List.java | Medium | Java | [Linked List, Two Pointers] | |
5 | Linked List Cycle II.java | Medium | Java | [Linked List, Two Pointers] | |
6 | Swap Nodes in Pairs.java | Medium | Java | [Linked List] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Plus One.java | Easy | Java | [Array, Math] | |
1 | Wiggle Sort.java | Medium | Java | [Array, Sort] | |
2 | 2 Sum.java | Easy | Java | [Array, Hash Table] | |
3 | 2 Sum II - Input array is sorted.java | Medium | Java | [Array, Binary Search, Two Pointers] | |
4 | 2 Sum II.java | Medium | Java | [Array, Binary Search, Two Pointers] | |
5 | Jump Game.java | Medium | Java | [Array, Greedy] | |
6 | Maximum Product Subarray.java | Medium | Java | [Array, DP] | |
7 | 3 Sum Closest.java | Medium | Java | [Array, Two Pointers] | |
8 | Triangle Count.java | Medium | Java | [Array] | |
9 | 3 Sum.java | Medium | Java | [Array, Two Pointers] | |
10 | Longest Continuous Increasing Subsequence.java | Easy | Java | [Array, DP] | |
11 | Unique Paths II.java | Medium | Java | [Array, DP] | |
12 | Best Time to Buy and Sell Stock I.java | Easy | Java | [Array, DP] | |
13 | Best Time to Buy and Sell Stock II.java | Easy | Java | [Array, Greedy] | |
14 | Best Time to Buy and Sell Stock III .java | Hard | Java | [Array, DP] | |
15 | 3 Sum Smaller.java | Medium | Java | [Array, Two Pointers] | |
16 | Array Partition I.java | Easy | Java | [Array] | |
17 | 1-bit and 2-bit Characters.java | Easy | Java | [Array] | |
18 | Non-decreasing Array.java | Easy | Java | [Array] | |
19 | Max Consecutive Ones.java | Easy | Java | [Array] | |
20 | Find All Numbers Disappeared in an Array.java | Easy | Java | [Array] | |
21 | Maximum Average Subarray I.java | Easy | Java | [Array] | |
22 | Largest Number At Least Twice of Others.java | Easy | Java | [Array] | |
23 | Toeplitz Matrix.java | Easy | Java | [Array] | |
24 | Find Peak Element.java | Medium | Java | [Array, Binary Search] | |
25 | Majority Element.java | Easy | Java | [Array, Bit Manipulation, Divide and Conquer] | |
26 | Construct Binary Tree from Inorder and Preorder Traversal.java | Medium | Java | [Array, DFS, Tree] | |
27 | Minimum Size Subarray Sum.java | Medium | Java | [Array, Binary Search, Two Pointers] | |
28 | Find Minimum in Rotated Sorted Array.java | Medium | Java | [Array, Binary Search] | |
29 | Find Minimum in Rotated Sorted Array II.java | Hard | Java | [Array, Binary Search] | |
30 | Word Search.java | Medium | Java | [Array, Backtracking] | |
31 | Trapping Rain Water.java | Hard | Java | [Array, Stack, Two Pointers] | |
32 | Largest Rectangle in Histogram.java | Hard | Java | [Array, Monotonous Stack, Stack] | |
33 | Find the Duplicate Number.java | Medium | Java | [Array, Binary Search, Two Pointers] | |
34 | Game of Life.java | Medium | Java | [Array] | |
35 | Maximum Average Subarray II.java | Review | Java | [Array, Binary Search] | |
36 | Number of Airplane in the sky.java | Medium | Java | [Array, Interval, Sort, Sweep Line] | |
37 | Unique Path.java | Medium | Java | [Array, Coordinate DP, DP] | |
38 | Maximal Rectangle.java | Hard | Java | [Array, DP, Hash Table, Stack] | |
39 | Minimum Path Sum.java | Medium | Java | [Array, Coordinate DP, DP] | |
40 | Coins in a Line II.java | Medium | Java | [Array, DP, Game Theory, Memoization, MiniMax] | |
41 | Coins in a Line III.java | Hard | Java | [Array, DP, Game Theory, Interval DP, Memoization] | |
42 | Contains Duplicate.java | Easy | Java | [Array, Hash Table] | |
43 | Contains Duplicate II.java | Easy | Java | [Array, Hash Table] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Building Outline.java | Review | Java | [Binary Indexed Tree, Divide and Conquer, Heap, Segment Tree, Sweep Line] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Clone Graph.java | Medium | Java | [BFS, DFS, Graph] | |
1 | Graph Valid Tree.java | Medium | Java | [BFS, DFS, Graph, Union Find] | |
2 | Course Schedule.java | Medium | Java | [BFS, DFS, Graph, Topological Sort] | |
3 | Course Schedule II.java | Medium | Java | [BFS, DFS, Graph, Topological Sort] | |
4 | Alien Dictionary.java | Hard | Java | [BFS, Backtracking, DFS, Graph, Topological Sort] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Nim Game.java | Easy | Java | [Brainteaser, DP, Game Theory] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Connecting Graph.java | Medium | Java | [Union Find] | |
1 | Connecting Graph II.java | Medium | Java | [Union Find] | |
2 | Connecting Graph III.java | Medium | Java | [Union Find] | |
3 | Number of Islands.java | Medium | Java | [BFS, DFS, Union Find] | |
4 | Number of Islands II.java | Hard | Java | [Union Find] | |
5 | Graph Valid Tree.java | Medium | Java | [BFS, DFS, Graph, Union Find] | |
6 | Surrounded Regions.java | Review | Java | [BFS, DFS, Union Find] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Longest Increasing Subsequence.java | Medium | Java | [Binary Search, DP, Memoization, Sequence DP] | |
1 | Longest Increasing Path in a Matrix.java | Hard | Java | [DFS, DP, Memoization, Topological Sort] | |
2 | Coins in a Line II.java | Medium | Java | [Array, DP, Game Theory, Memoization, MiniMax] | |
3 | Climbing Stairs.java | Easy | Java | [DP, Memoization, Sequence DP] | |
4 | Coins in a Line III.java | Hard | Java | [Array, DP, Game Theory, Interval DP, Memoization] | |
5 | Burst Balloons.java | Hard | Java | [DP, Divide and Conquer, Memoization, Range DP] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Meeting Rooms.java | Easy | Java | [Sort, Sweep Line] | |
1 | Number of Airplane in the sky.java | Medium | Java | [Array, Interval, Sort, Sweep Line] | |
2 | Meeting Rooms II.java | Medium | Java | [Greedy, Heap, Sort, Sweep Line] | |
3 | Building Outline.java | Review | Java | [Binary Indexed Tree, Divide and Conquer, Heap, Segment Tree, Sweep Line] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Binary Tree Postorder Traversal.java | Medium | Java | [Stack, Tree, Two Stacks] |
Squence | Problem | Level | Language | Tags | Video Tutorial |
---|---|---|---|---|---|
0 | Number of Airplane in the sky.java | Medium | Java | [Array, Interval, Sort, Sweep Line] |