# LintCode

**Repository Path**: carterchou/LintCode

## Basic Information

- **Project Name**: LintCode
- **Description**: Java Solutions to problems on LintCode/LeetCode
- **Primary Language**: Java
- **License**: Not specified
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2021-02-27
- **Last Updated**: 2021-02-27

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

# Java Algorithm Problems

### 程序员的一天
从开始这个Github已经有将近两年时间, 很高兴这个repo可以帮到有需要的人. 我一直认为, 知识本身是无价的, 因此每逢闲暇, 我就会来维护这个repo, 给刷题的朋友们一些我的想法和见解. 下面来简单介绍一下这个repo:

**README.md**: 所有所做过的题目

**ReviewPage.md**: 所有题目的总结和归纳（不断完善中）

**KnowledgeHash2.md**: 对所做过的知识点的一些笔记

**SystemDesign.md**: 对系统设计的一些笔记

**Future Milestone**: 我准备将一些有意思的题目，做成视频的形式给大家参考

希望大家学习顺利, 对未来充满希望(程序员也是找到好老板的!)
有问题可以给我写邮件(wangdeve@gmail.com), 或者在GitHub上发issue给我.

| Squence | Problem       | Level  | Language  | Tags | Video Tutorial|
|:-------:|:--------------|:------:|:---------:|:----:|:-------------:|
|0|[Binary Representation.java](https://github.com/awangdev/LintCode/blob/master/Java/Binary%20Representation.java)|Hard|Java|[]||
|1|[Binary Tree Longest Consecutive Sequence.java](https://github.com/awangdev/LintCode/blob/master/Java/Binary%20Tree%20Longest%20Consecutive%20Sequence.java)|Medium|Java|[Tree, dfs]||
|2|[Binary Tree Maximum Path Sum II.java](https://github.com/awangdev/LintCode/blob/master/Java/Binary%20Tree%20Maximum%20Path%20Sum%20II.java)|Medium|Java|[]||
|3|[Binary Tree Right Side View.java](https://github.com/awangdev/LintCode/blob/master/Java/Binary%20Tree%20Right%20Side%20View.java)|Medium|Java|[]||
|4|[Binary Tree Serialization.java](https://github.com/awangdev/LintCode/blob/master/Java/Binary%20Tree%20Serialization.java)|Medium|Java|[]||
|5|[Binary Tree Zigzag Level Order Traversal.java](https://github.com/awangdev/LintCode/blob/master/Java/Binary%20Tree%20Zigzag%20Level%20Order%20Traversal.java)|Medium|Java|[]||
|6|[ColorGrid.java](https://github.com/awangdev/LintCode/blob/master/Java/ColorGrid.java)|Medium|Java|[]||
|7|[Combination Sum II.java](https://github.com/awangdev/LintCode/blob/master/Java/Combination%20Sum%20II.java)|Medium|Java|[]||
|8|[Combination Sum.java](https://github.com/awangdev/LintCode/blob/master/Java/Combination%20Sum.java)|Medium|Java|[]||
|9|[Combinations.java](https://github.com/awangdev/LintCode/blob/master/Java/Combinations.java)|Medium|Java|[]||
|10|[Construct Binary Tree from Inorder and Postorder Traversal.java](https://github.com/awangdev/LintCode/blob/master/Java/Construct%20Binary%20Tree%20from%20Inorder%20and%20Postorder%20Traversal.java)|Medium|Java|[]||
|11|[Container With Most Water.java](https://github.com/awangdev/LintCode/blob/master/Java/Container%20With%20Most%20Water.java)|Medium|Java|[]||
|12|[Convert Binary Search Tree to Doubly Linked List.java](https://github.com/awangdev/LintCode/blob/master/Java/Convert%20Binary%20Search%20Tree%20to%20Doubly%20Linked%20List.java)|Medium|Java|[BST]||
|13|[Copy List with Random Pointer.java](https://github.com/awangdev/LintCode/blob/master/Java/Copy%20List%20with%20Random%20Pointer.java)|Medium|Java|[]||
|14|[Count of Smaller Number before itself.java](https://github.com/awangdev/LintCode/blob/master/Java/Count%20of%20Smaller%20Number%20before%20itself.java)|Hard|Java|[]||
|15|[Count of Smaller Number.java](https://github.com/awangdev/LintCode/blob/master/Java/Count%20of%20Smaller%20Number.java)|Medium|Java|[]||
|16|[Delete Digits.java](https://github.com/awangdev/LintCode/blob/master/Java/Delete%20Digits.java)|Medium|Java|[]||
|17|[Encode and Decode Strings.java](https://github.com/awangdev/LintCode/blob/master/Java/Encode%20and%20Decode%20Strings.java)|Medium|Java|[]||
|18|[Fast Power.java](https://github.com/awangdev/LintCode/blob/master/Java/Fast%20Power.java)|Medium|Java|[]||
|19|[Find the Connected Component in the Undirected Graph.java](https://github.com/awangdev/LintCode/blob/master/Java/Find%20the%20Connected%20Component%20in%20the%20Undirected%20Graph.java)|Medium|Java|[]||
|20|[Find the Weak Connected Component in the Directed Graph.java](https://github.com/awangdev/LintCode/blob/master/Java/Find%20the%20Weak%20Connected%20Component%20in%20the%20Directed%20Graph.java)|Medium|Java|[]||
|21|[Flatten 2D Vector.java](https://github.com/awangdev/LintCode/blob/master/Java/Flatten%202D%20Vector.java)|Medium|Java|[]||
|22|[Fraction to Recurring Decimal.java](https://github.com/awangdev/LintCode/blob/master/Java/Fraction%20to%20Recurring%20Decimal.java)|Medium|Java|[]||
|23|[Generate Parentheses.java](https://github.com/awangdev/LintCode/blob/master/Java/Generate%20Parentheses.java)|Medium|Java|[]||
|24|[Gray Code.java](https://github.com/awangdev/LintCode/blob/master/Java/Gray%20Code.java)|Medium|Java|[]||
|25|[Group Shifted Strings.java](https://github.com/awangdev/LintCode/blob/master/Java/Group%20Shifted%20Strings.java)|Easy|Java|[]||
|26|[H-Index II.java](https://github.com/awangdev/LintCode/blob/master/Java/H-Index%20II.java)|Medium|Java|[]||
|27|[H-Index.java](https://github.com/awangdev/LintCode/blob/master/Java/H-Index.java)|Medium|Java|[]||
|28|[Hamming Distance.java](https://github.com/awangdev/LintCode/blob/master/Java/Hamming%20Distance.java)|Easy|Java|[]||
|29|[Happy Number.java](https://github.com/awangdev/LintCode/blob/master/Java/Happy%20Number.java)|Easy|Java|[]||
|30|[HashHeap.java](https://github.com/awangdev/LintCode/blob/master/Java/HashHeap.java)|Hard|Java|[]||
|31|[HashWithArray.java](https://github.com/awangdev/LintCode/blob/master/Java/HashWithArray.java)|Easy|Java|[]||
|32|[HashWithCustomizedClass(LinkedList).java](https://github.com/awangdev/LintCode/blob/master/Java/HashWithCustomizedClass(LinkedList).java)|Medium|Java|[]||
|33|[Heapify.java](https://github.com/awangdev/LintCode/blob/master/Java/Heapify.java)|Medium|Java|[]||
|34|[Heaters.java](https://github.com/awangdev/LintCode/blob/master/Java/Heaters.java)|Easy|Java|[]||
|35|[IndexMatch.java](https://github.com/awangdev/LintCode/blob/master/Java/IndexMatch.java)|Easy|Java|[]||
|36|[Inorder Successor in Binary Search Tree.java](https://github.com/awangdev/LintCode/blob/master/Java/Inorder%20Successor%20in%20Binary%20Search%20Tree.java)|Medium|Java|[BST]||
|37|[Insert Interval.java](https://github.com/awangdev/LintCode/blob/master/Java/Insert%20Interval.java)|Easy|Java|[]||
|38|[Insert Node in a Binary Search Tree .java](https://github.com/awangdev/LintCode/blob/master/Java/Insert%20Node%20in%20a%20Binary%20Search%20Tree%20.java)|Easy|Java|[BST]||
|39|[Intersection of Two Arrays.java](https://github.com/awangdev/LintCode/blob/master/Java/Intersection%20of%20Two%20Arrays.java)|Easy|Java|[]||
|40|[Intersection of Two Linked Lists.java](https://github.com/awangdev/LintCode/blob/master/Java/Intersection%20of%20Two%20Linked%20Lists.java)|Easy|Java|[Linked List]||
|41|[Interval Minimum Number.java](https://github.com/awangdev/LintCode/blob/master/Java/Interval%20Minimum%20Number.java)|Medium|Java|[]||
|42|[Interval Sum II.java](https://github.com/awangdev/LintCode/blob/master/Java/Interval%20Sum%20II.java)|Hard|Java|[]||
|43|[Interval Sum.java](https://github.com/awangdev/LintCode/blob/master/Java/Interval%20Sum.java)|Medium|Java|[]||
|44|[Isomorphic Strings.java](https://github.com/awangdev/LintCode/blob/master/Java/Isomorphic%20Strings.java)|Easy|Java|[]||
|45|[Jewels and Stones.java](https://github.com/awangdev/LintCode/blob/master/Java/Jewels%20and%20Stones.java)|Easy|Java|[Hash Table]||
|46|[Kth Largest Element.java](https://github.com/awangdev/LintCode/blob/master/Java/Kth%20Largest%20Element.java)|Medium|Java|[]||
|47|[Kth Smallest Element in a BST.java](https://github.com/awangdev/LintCode/blob/master/Java/Kth%20Smallest%20Element%20in%20a%20BST.java)|Medium|Java|[BST]||
|48|[Kth Smallest Sum In Two Sorted Arrays.java](https://github.com/awangdev/LintCode/blob/master/Java/Kth%20Smallest%20Sum%20In%20Two%20Sorted%20Arrays.java)|Hard|Java|[]||
|49|[Longest Common Prefix.java](https://github.com/awangdev/LintCode/blob/master/Java/Longest%20Common%20Prefix.java)|Medium|Java|[]||
|50|[Longest Palindromic Substring.java](https://github.com/awangdev/LintCode/blob/master/Java/Longest%20Palindromic%20Substring.java)|Medium|Java|[]||
|51|[Longest Univalue Path.java](https://github.com/awangdev/LintCode/blob/master/Java/Longest%20Univalue%20Path.java)|Easy|Java|[]||
|52|[Majority Number II.java](https://github.com/awangdev/LintCode/blob/master/Java/Majority%20Number%20II.java)|Medium|Java|[]||
|53|[Majority Number III.java](https://github.com/awangdev/LintCode/blob/master/Java/Majority%20Number%20III.java)|Medium|Java|[]||
|54|[Matrix Zigzag Traversal.java](https://github.com/awangdev/LintCode/blob/master/Java/Matrix%20Zigzag%20Traversal.java)|Easy|Java|[]||
|55|[Max Area of Island.java](https://github.com/awangdev/LintCode/blob/master/Java/Max%20Area%20of%20Island.java)|Easy|Java|[]||
|56|[Maximum Subarray III.java](https://github.com/awangdev/LintCode/blob/master/Java/Maximum%20Subarray%20III.java)|Hard|Java|[]||
|57|[Median of two Sorted Arrays.java](https://github.com/awangdev/LintCode/blob/master/Java/Median%20of%20two%20Sorted%20Arrays.java)|Hard|Java|[]||
|58|[Merge k Sorted Arrays.java](https://github.com/awangdev/LintCode/blob/master/Java/Merge%20k%20Sorted%20Arrays.java)|Medium|Java|[]||
|59|[Merge k Sorted Lists.java](https://github.com/awangdev/LintCode/blob/master/Java/Merge%20k%20Sorted%20Lists.java)|Medium|Java|[]||
|60|[Merge Sorted Array II.java](https://github.com/awangdev/LintCode/blob/master/Java/Merge%20Sorted%20Array%20II.java)|N/A|Java|[]||
|61|[Minimum Absolute Difference in BST.java](https://github.com/awangdev/LintCode/blob/master/Java/Minimum%20Absolute%20Difference%20in%20BST.java)|Easy|Java|[BST]||
|62|[Minimum Height Trees.java](https://github.com/awangdev/LintCode/blob/master/Java/Minimum%20Height%20Trees.java)|Medium|Java|[]||
|63|[Minimum Subarray.java](https://github.com/awangdev/LintCode/blob/master/Java/Minimum%20Subarray.java)|N/A|Java|[]||
|64|[Missing Ranges.java](https://github.com/awangdev/LintCode/blob/master/Java/Missing%20Ranges.java)|Medium|Java|[]||
|65|[Multiply Strings.java](https://github.com/awangdev/LintCode/blob/master/Java/Multiply%20Strings.java)|Medium|Java|[]||
|66|[Next Permutation.java](https://github.com/awangdev/LintCode/blob/master/Java/Next%20Permutation.java)|Medium|Java|[]||
|67|[Nth to Last Node in List.java](https://github.com/awangdev/LintCode/blob/master/Java/Nth%20to%20Last%20Node%20in%20List.java)|N/A|Java|[]||
|68|[Number Triangles.java](https://github.com/awangdev/LintCode/blob/master/Java/Number%20Triangles.java)|N/A|Java|[]||
|69|[O(1) Check Power of 2.java](https://github.com/awangdev/LintCode/blob/master/Java/O(1)%20Check%20Power%20of%202.java)|N/A|Java|[]||
|70|[Paint Fence.java](https://github.com/awangdev/LintCode/blob/master/Java/Paint%20Fence.java)|Easy|Java|[]||
|71|[Palindrome Permutation II.java](https://github.com/awangdev/LintCode/blob/master/Java/Palindrome%20Permutation%20II.java)|Medium|Java|[]||
|72|[Partition Array by Odd and Even.java](https://github.com/awangdev/LintCode/blob/master/Java/Partition%20Array%20by%20Odd%20and%20Even.java)|N/A|Java|[]||
|73|[Partition Array.java](https://github.com/awangdev/LintCode/blob/master/Java/Partition%20Array.java)|N/A|Java|[]||
|74|[Partition List.java](https://github.com/awangdev/LintCode/blob/master/Java/Partition%20List.java)|Medium|Java|[]||
|75|[Pascal's Triangle II.java](https://github.com/awangdev/LintCode/blob/master/Java/Pascal's%20Triangle%20II.java)|Easy|Java|[]||
|76|[Peeking Iterator.java](https://github.com/awangdev/LintCode/blob/master/Java/Peeking%20Iterator.java)|Medium|Java|[BST]||
|77|[Permutation Index.java](https://github.com/awangdev/LintCode/blob/master/Java/Permutation%20Index.java)|Easy|Java|[]||
|78|[Permutation Sequence.java](https://github.com/awangdev/LintCode/blob/master/Java/Permutation%20Sequence.java)|Medium|Java|[]||
|79|[Permutations.java](https://github.com/awangdev/LintCode/blob/master/Java/Permutations.java)|Medium|Java|[]||
|80|[Populating Next Right Pointers in Each Node II.java](https://github.com/awangdev/LintCode/blob/master/Java/Populating%20Next%20Right%20Pointers%20in%20Each%20Node%20II.java)|Hard|Java|[]||
|81|[Product of Array Exclude Itself.java](https://github.com/awangdev/LintCode/blob/master/Java/Product%20of%20Array%20Exclude%20Itself.java)|N/A|Java|[]||
|82|[Recover Rotated Sorted Array.java](https://github.com/awangdev/LintCode/blob/master/Java/Recover%20Rotated%20Sorted%20Array.java)|N/A|Java|[]||
|83|[Rehashing.java](https://github.com/awangdev/LintCode/blob/master/Java/Rehashing.java)|Medium|Java|[]||
|84|[Remove Duplicates from Unsorted List.java](https://github.com/awangdev/LintCode/blob/master/Java/Remove%20Duplicates%20from%20Unsorted%20List.java)|N/A|Java|[]||
|85|[Remove Invalid Parentheses.java](https://github.com/awangdev/LintCode/blob/master/Java/Remove%20Invalid%20Parentheses.java)|Hard|Java|[]||
|86|[Remove Node in Binary Search Tree.java](https://github.com/awangdev/LintCode/blob/master/Java/Remove%20Node%20in%20Binary%20Search%20Tree.java)|Hard|Java|[BST]||
|87|[Reorder List.java](https://github.com/awangdev/LintCode/blob/master/Java/Reorder%20List.java)|Medium|Java|[]||
|88|[Reshape the Matrix.java](https://github.com/awangdev/LintCode/blob/master/Java/Reshape%20the%20Matrix.java)|Easy|Java|[]||
|89|[Restore IP Addresses.java](https://github.com/awangdev/LintCode/blob/master/Java/Restore%20IP%20Addresses.java)|Medium|Java|[]||
|90|[Reverse String.java](https://github.com/awangdev/LintCode/blob/master/Java/Reverse%20String.java)|Easy|Java|[]||
|91|[Reverse Words in a String II.java](https://github.com/awangdev/LintCode/blob/master/Java/Reverse%20Words%20in%20a%20String%20II.java)|Medium|Java|[]||
|92|[Reverse Words in a String.java](https://github.com/awangdev/LintCode/blob/master/Java/Reverse%20Words%20in%20a%20String.java)|Medium|Java|[]||
|93|[Roman to Integer.java](https://github.com/awangdev/LintCode/blob/master/Java/Roman%20to%20Integer.java)|Easy|Java|[]||
|94|[Rotate Image.java](https://github.com/awangdev/LintCode/blob/master/Java/Rotate%20Image.java)|Medium|Java|[]||
|95|[Rotate List.java](https://github.com/awangdev/LintCode/blob/master/Java/Rotate%20List.java)|Medium|Java|[]||
|96|[Search a 2D Matrix II.java](https://github.com/awangdev/LintCode/blob/master/Java/Search%20a%202D%20Matrix%20II.java)|Medium|Java|[]||
|97|[Search a 2D Matrix.java](https://github.com/awangdev/LintCode/blob/master/Java/Search%20a%202D%20Matrix.java)|Medium|Java|[]||
|98|[Search for a Range.java](https://github.com/awangdev/LintCode/blob/master/Java/Search%20for%20a%20Range.java)|Medium|Java|[]||
|99|[Search Insert Position.java](https://github.com/awangdev/LintCode/blob/master/Java/Search%20Insert%20Position.java)|Easy|Java|[]||
|100|[Search Range in Binary Search Tree .java](https://github.com/awangdev/LintCode/blob/master/Java/Search%20Range%20in%20Binary%20Search%20Tree%20.java)|Medium|Java|[BST]||
|101|[Search Rotated in Sorted Array II.java](https://github.com/awangdev/LintCode/blob/master/Java/Search%20Rotated%20in%20Sorted%20Array%20II.java)|N/A|Java|[]||
|102|[Search Rotated in Sorted Array.java](https://github.com/awangdev/LintCode/blob/master/Java/Search%20Rotated%20in%20Sorted%20Array.java)|Hard|Java|[]||
|103|[Segment Tree Build II.java](https://github.com/awangdev/LintCode/blob/master/Java/Segment%20Tree%20Build%20II.java)|Medium|Java|[]||
|104|[Segment Tree Build.java](https://github.com/awangdev/LintCode/blob/master/Java/Segment%20Tree%20Build.java)|Medium|Java|[]||
|105|[Segment Tree Modify.java](https://github.com/awangdev/LintCode/blob/master/Java/Segment%20Tree%20Modify.java)|Medium|Java|[]||
|106|[Segment Tree Query II.java](https://github.com/awangdev/LintCode/blob/master/Java/Segment%20Tree%20Query%20II.java)|Medium|Java|[]||
|107|[Segment Tree Query.java](https://github.com/awangdev/LintCode/blob/master/Java/Segment%20Tree%20Query.java)|Medium|Java|[]||
|108|[Serilization and Deserialization Of Binary Tree.java](https://github.com/awangdev/LintCode/blob/master/Java/Serilization%20and%20Deserialization%20Of%20Binary%20Tree.java)|N/A|Java|[]||
|109|[Shortest Word Distance.java](https://github.com/awangdev/LintCode/blob/master/Java/Shortest%20Word%20Distance.java)|Easy|Java|[]||
|110|[Single Number II.java](https://github.com/awangdev/LintCode/blob/master/Java/Single%20Number%20II.java)|Medium|Java|[]||
|111|[Single Number III.java](https://github.com/awangdev/LintCode/blob/master/Java/Single%20Number%20III.java)|Medium|Java|[]||
|112|[Single Number.java](https://github.com/awangdev/LintCode/blob/master/Java/Single%20Number.java)|Easy|Java|[]||
|113|[Sliding Window Maximum.java](https://github.com/awangdev/LintCode/blob/master/Java/Sliding%20Window%20Maximum.java)|Hard|Java|[]||
|114|[Sort Color.java](https://github.com/awangdev/LintCode/blob/master/Java/Sort%20Color.java)|Medium|Java|[]||
|115|[Sort Colors II.java](https://github.com/awangdev/LintCode/blob/master/Java/Sort%20Colors%20II.java)|N/A|Java|[]||
|116|[Sort Letters by Case.java](https://github.com/awangdev/LintCode/blob/master/Java/Sort%20Letters%20by%20Case.java)|N/A|Java|[]||
|117|[Sort List.java](https://github.com/awangdev/LintCode/blob/master/Java/Sort%20List.java)|Medium|Java|[]||
|118|[Space Replacement.java](https://github.com/awangdev/LintCode/blob/master/Java/Space%20Replacement.java)|N/A|Java|[]||
|119|[Stone Game.java](https://github.com/awangdev/LintCode/blob/master/Java/Stone%20Game.java)|N/A|Java|[]||
|120|[String Permutation.java](https://github.com/awangdev/LintCode/blob/master/Java/String%20Permutation.java)|Easy|Java|[]||
|121|[String to Integer(atoi).java](https://github.com/awangdev/LintCode/blob/master/Java/String%20to%20Integer(atoi).java)|Easy|Java|[]||
|122|[Strobogrammatic Number II.java](https://github.com/awangdev/LintCode/blob/master/Java/Strobogrammatic%20Number%20II.java)|Medium|Java|[]||
|123|[Strobogrammatic Number.java](https://github.com/awangdev/LintCode/blob/master/Java/Strobogrammatic%20Number.java)|Easy|Java|[]||
|124|[Subarray Sum Closest.java](https://github.com/awangdev/LintCode/blob/master/Java/Subarray%20Sum%20Closest.java)|Medium|Java|[]||
|125|[Subarray Sum.java](https://github.com/awangdev/LintCode/blob/master/Java/Subarray%20Sum.java)|Easy|Java|[]||
|126|[Subset.java](https://github.com/awangdev/LintCode/blob/master/Java/Subset.java)|Medium|Java|[]||
|127|[Subsets II.java](https://github.com/awangdev/LintCode/blob/master/Java/Subsets%20II.java)|Medium|Java|[]||
|128|[Summary Ranges.java](https://github.com/awangdev/LintCode/blob/master/Java/Summary%20Ranges.java)|Medium|Java|[]||
|129|[The Smallest Difference.java](https://github.com/awangdev/LintCode/blob/master/Java/The%20Smallest%20Difference.java)|N/A|Java|[]||
|130|[Top K Frequent Elements.java](https://github.com/awangdev/LintCode/blob/master/Java/Top%20K%20Frequent%20Elements.java)|Medium|Java|[]||
|131|[Top K Frequent Words.java](https://github.com/awangdev/LintCode/blob/master/Java/Top%20K%20Frequent%20Words.java)|Medium|Java|[]||
|132|[Topological Sorting.java](https://github.com/awangdev/LintCode/blob/master/Java/Topological%20Sorting.java)|Medium|Java|[]||
|133|[Total Occurrence of Target.java](https://github.com/awangdev/LintCode/blob/master/Java/Total%20Occurrence%20of%20Target.java)|N/A|Java|[]||
|134|[Trailing Zeros.java](https://github.com/awangdev/LintCode/blob/master/Java/Trailing%20Zeros.java)|N/A|Java|[]||
|135|[Tweaked Identical Binary Tree.java](https://github.com/awangdev/LintCode/blob/master/Java/Tweaked%20Identical%20Binary%20Tree.java)|Easy|Java|[DFS, Tree]||
|136|[Two Lists Sum.java](https://github.com/awangdev/LintCode/blob/master/Java/Two%20Lists%20Sum.java)|N/A|Java|[]||
|137|[Two Strings Are Anagrams.java](https://github.com/awangdev/LintCode/blob/master/Java/Two%20Strings%20Are%20Anagrams.java)|Easy|Java|[]||
|138|[Ugly Number II.java](https://github.com/awangdev/LintCode/blob/master/Java/Ugly%20Number%20II.java)|Medium|Java|[]||
|139|[Ugly Number.java](https://github.com/awangdev/LintCode/blob/master/Java/Ugly%20Number.java)|Medium|Java|[]||
|140|[Unique Binary Search Tree II.java](https://github.com/awangdev/LintCode/blob/master/Java/Unique%20Binary%20Search%20Tree%20II.java)|Medium|Java|[BST]||
|141|[Unique Characters.java](https://github.com/awangdev/LintCode/blob/master/Java/Unique%20Characters.java)|N/A|Java|[]||
|142|[Unique Word Abbreviation.java](https://github.com/awangdev/LintCode/blob/master/Java/Unique%20Word%20Abbreviation.java)|Medium|Java|[]||
|143|[Valid Parentheses.java](https://github.com/awangdev/LintCode/blob/master/Java/Valid%20Parentheses.java)|Easy|Java|[]||
|144|[Valid Sudoku.java](https://github.com/awangdev/LintCode/blob/master/Java/Valid%20Sudoku.java)|Easy|Java|[]||
|145|[Word Break.java](https://github.com/awangdev/LintCode/blob/master/Java/Word%20Break.java)|Medium|Java|[]||
|146|[Word Ladder II.java](https://github.com/awangdev/LintCode/blob/master/Java/Word%20Ladder%20II.java)|Hard|Java|[]||
|147|[Word Ladder.java](https://github.com/awangdev/LintCode/blob/master/Java/Word%20Ladder.java)|Medium|Java|[]||
|148|[Word Pattern.java](https://github.com/awangdev/LintCode/blob/master/Java/Word%20Pattern.java)|Easy|Java|[]||
|149|[Zigzag Iterator.java](https://github.com/awangdev/LintCode/blob/master/Java/Zigzag%20Iterator.java)|Medium|Java|[BST]||
|150|[Find Anagram Mappings.java](https://github.com/awangdev/LintCode/blob/master/Java/Find%20Anagram%20Mappings.java)|Easy|Java|[Hash Table]||
|151|[Judge Route Circle.java](https://github.com/awangdev/LintCode/blob/master/Java/Judge%20Route%20Circle.java)|Easy|Java|[String]||
|152|[Island Perimeter.java](https://github.com/awangdev/LintCode/blob/master/Java/Island%20Perimeter.java)|Easy|Java|[Hash Table]||
|153|[First Unique Character in a String.java](https://github.com/awangdev/LintCode/blob/master/Java/First%20Unique%20Character%20in%20a%20String.java)|Easy|Java|[Hash Table, String]||
|154|[Power of Three.java](https://github.com/awangdev/LintCode/blob/master/Java/Power%20of%20Three.java)|Easy|Java|[Math]||
|155|[Plus One.java](https://github.com/awangdev/LintCode/blob/master/Java/Plus%20One.java)|Easy|Java|[Array, Math]||
|156|[Power of Two.java](https://github.com/awangdev/LintCode/blob/master/Java/Power%20of%20Two.java)|Easy|Java|[Bit Manipulation, Math]||
|157|[Reverse Vowels of a String.java](https://github.com/awangdev/LintCode/blob/master/Java/Reverse%20Vowels%20of%20a%20String.java)|Easy|Java|[String, Two Pointers]||
|158|[Guess Number Higher or Lower.java](https://github.com/awangdev/LintCode/blob/master/Java/Guess%20Number%20Higher%20or%20Lower.java)|Easy|Java|[Binary Search]||
|159|[Encode and Decode TinyURL.java](https://github.com/awangdev/LintCode/blob/master/Java/Encode%20and%20Decode%20TinyURL.java)|Medium|Java|[Hash Table, Math]||
|160|[Wiggle Sort.java](https://github.com/awangdev/LintCode/blob/master/Java/Wiggle%20Sort.java)|Medium|Java|[Array, Sort]||
|161|[Queue Reconstruction by Height.java](https://github.com/awangdev/LintCode/blob/master/Java/Queue%20Reconstruction%20by%20Height.java)|Medium|Java|[Greedy]||
|162|[2 Sum.java](https://github.com/awangdev/LintCode/blob/master/Java/2%20Sum.java)|Easy|Java|[Array, Hash Table]||
|163|[2 Sum II - Input array is sorted.java](https://github.com/awangdev/LintCode/blob/master/Java/2%20Sum%20II%20-%20Input%20array%20is%20sorted.java)|Medium|Java|[Array, Binary Search, Two Pointers]||
|164|[2 Sum II.java](https://github.com/awangdev/LintCode/blob/master/Java/2%20Sum%20II.java)|Medium|Java|[Array, Binary Search, Two Pointers]||
|165|[Coin Change.java](https://github.com/awangdev/LintCode/blob/master/Java/Coin%20Change.java)|Medium|Java|[DP, Memoization, Sequence DP]||
|166|[Maximum Product Subarray.java](https://github.com/awangdev/LintCode/blob/master/Java/Maximum%20Product%20Subarray.java)|Medium|Java|[Array, DP]||
|167|[3 Sum Closest.java](https://github.com/awangdev/LintCode/blob/master/Java/3%20Sum%20Closest.java)|Medium|Java|[Array, Two Pointers]||
|168|[Triangle Count.java](https://github.com/awangdev/LintCode/blob/master/Java/Triangle%20Count.java)|Medium|Java|[Array]||
|169|[3 Sum.java](https://github.com/awangdev/LintCode/blob/master/Java/3%20Sum.java)|Medium|Java|[Array, Two Pointers]||
|170|[4 Sum.java](https://github.com/awangdev/LintCode/blob/master/Java/4%20Sum.java)|Medium|Java|[Hash Table]||
|171|[k Sum.java](https://github.com/awangdev/LintCode/blob/master/Java/k%20Sum.java)|Hard|Java|[DP]||
|172|[Longest Increasing Subsequence.java](https://github.com/awangdev/LintCode/blob/master/Java/Longest%20Increasing%20Subsequence.java)|Medium|Java|[Binary Search, Coordinate DP, DP, Memoization, Sequence DP]||
|173|[Unique Binary Search Tree.java](https://github.com/awangdev/LintCode/blob/master/Java/Unique%20Binary%20Search%20Tree.java)|Medium|Java|[BST, DP, Tree]||
|174|[Trim a Binary Search Tree.java](https://github.com/awangdev/LintCode/blob/master/Java/Trim%20a%20Binary%20Search%20Tree.java)|Easy|Java|[BST, Tree]||
|175|[Unique Paths II.java](https://github.com/awangdev/LintCode/blob/master/Java/Unique%20Paths%20II.java)|Medium|Java|[Array, Coordinate DP, DP]||
|176|[Bomb Enemy.java](https://github.com/awangdev/LintCode/blob/master/Java/Bomb%20Enemy.java)|Medium|Java|[Coordinate DP, DP]||
|177|[3 Sum Smaller.java](https://github.com/awangdev/LintCode/blob/master/Java/3%20Sum%20Smaller.java)|Medium|Java|[Array, Two Pointers]||
|178|[Array Partition I.java](https://github.com/awangdev/LintCode/blob/master/Java/Array%20Partition%20I.java)|Easy|Java|[Array]||
|179|[1-bit and 2-bit Characters.java](https://github.com/awangdev/LintCode/blob/master/Java/1-bit%20and%202-bit%20Characters.java)|Easy|Java|[Array]||
|180|[Non-decreasing Array.java](https://github.com/awangdev/LintCode/blob/master/Java/Non-decreasing%20Array.java)|Easy|Java|[Array]||
|181|[Max Consecutive Ones.java](https://github.com/awangdev/LintCode/blob/master/Java/Max%20Consecutive%20Ones.java)|Easy|Java|[Array]||
|182|[Find All Numbers Disappeared in an Array.java](https://github.com/awangdev/LintCode/blob/master/Java/Find%20All%20Numbers%20Disappeared%20in%20an%20Array.java)|Easy|Java|[Array]||
|183|[Maximum Average Subarray I.java](https://github.com/awangdev/LintCode/blob/master/Java/Maximum%20Average%20Subarray%20I.java)|Easy|Java|[Array]||
|184|[Largest Number At Least Twice of Others.java](https://github.com/awangdev/LintCode/blob/master/Java/Largest%20Number%20At%20Least%20Twice%20of%20Others.java)|Easy|Java|[Array]||
|185|[Toeplitz Matrix.java](https://github.com/awangdev/LintCode/blob/master/Java/Toeplitz%20Matrix.java)|Easy|Java|[Array]||
|186|[Sum of Two Integers.java](https://github.com/awangdev/LintCode/blob/master/Java/Sum%20of%20Two%20Integers.java)|Easy|Java|[Bit Manipulation]||
|187|[Swap Bits.java](https://github.com/awangdev/LintCode/blob/master/Java/Swap%20Bits.java)|Easy|Java|[Bit Manipulation]||
|188|[Update Bits.java](https://github.com/awangdev/LintCode/blob/master/Java/Update%20Bits.java)|Medium|Java|[Bit Manipulation]||
|189|[Maximum XOR of Two Numbers in an Array.java](https://github.com/awangdev/LintCode/blob/master/Java/Maximum%20XOR%20of%20Two%20Numbers%20in%20an%20Array.java)|Medium|Java|[Bit Manipulation, Trie]||
|190|[Perfect Squares.java](https://github.com/awangdev/LintCode/blob/master/Java/Perfect%20Squares.java)|Medium|Java|[BFS, DP, Math, Partition DP]||
|191|[Backpack VI.java](https://github.com/awangdev/LintCode/blob/master/Java/Backpack%20VI.java)|Medium|Java|[Backpack DP, DP]||
|192|[Copy Books.java](https://github.com/awangdev/LintCode/blob/master/Java/Copy%20Books.java)|Hard|Java|[Binary Search, DP, Partition DP]||
|193|[Valid Perfect Square.java](https://github.com/awangdev/LintCode/blob/master/Java/Valid%20Perfect%20Square.java)|Review|Java|[Binary Search, Math]||
|194|[Intersection of Two Arrays II.java](https://github.com/awangdev/LintCode/blob/master/Java/Intersection%20of%20Two%20Arrays%20II.java)|Easy|Java|[Binary Search, Hash Table, Sort, Two Pointers]||
|195|[Longest Palindromic Subsequence.java](https://github.com/awangdev/LintCode/blob/master/Java/Longest%20Palindromic%20Subsequence.java)|Medium|Java|[DP, Interval DP, Memoization]||
|196|[Scramble String.java](https://github.com/awangdev/LintCode/blob/master/Java/Scramble%20String.java)|Hard|Java|[DP, Interval DP, String]||
|197|[Binary Search Tree Iterator.java](https://github.com/awangdev/LintCode/blob/master/Java/Binary%20Search%20Tree%20Iterator.java)|Medium|Java|[BST, Design, Stack, Tree]||
|198|[Flatten Nested List Iterator.java](https://github.com/awangdev/LintCode/blob/master/Java/Flatten%20Nested%20List%20Iterator.java)|Medium|Java|[Design, Stack]||
|199|[Best Time to Buy and Sell Stock with Cooldown.java](https://github.com/awangdev/LintCode/blob/master/Java/Best%20Time%20to%20Buy%20and%20Sell%20Stock%20with%20Cooldown.java)|Medium|Java|[DP]||
|200|[Find Peak Element.java](https://github.com/awangdev/LintCode/blob/master/Java/Find%20Peak%20Element.java)|Medium|Java|[Array, Binary Search]||
|201|[Longest Common Subsequence.java](https://github.com/awangdev/LintCode/blob/master/Java/Longest%20Common%20Subsequence.java)|Medium|Java|[DP, Double Sequence DP]||
|202|[Interleaving String.java](https://github.com/awangdev/LintCode/blob/master/Java/Interleaving%20String.java)|Hard|Java|[DP, String]||
|203|[Letter Combinations of a Phone Number.java](https://github.com/awangdev/LintCode/blob/master/Java/Letter%20Combinations%20of%20a%20Phone%20Number.java)|Medium|Java|[Backtracking, String]||
|204|[Edit Distance.java](https://github.com/awangdev/LintCode/blob/master/Java/Edit%20Distance.java)|Hard|Java|[DP, Double Sequence DP, String]||
|205|[Distinct Subsequences.java](https://github.com/awangdev/LintCode/blob/master/Java/Distinct%20Subsequences.java)|Hard|Java|[DP, String]||
|206|[Regular Expression Matching.java](https://github.com/awangdev/LintCode/blob/master/Java/Regular%20Expression%20Matching.java)|Review|Java|[Backtracking, DP, String]||
|207|[Majority Element.java](https://github.com/awangdev/LintCode/blob/master/Java/Majority%20Element.java)|Easy|Java|[Array, Bit Manipulation, Divide and Conquer]||
|208|[Wildcard Matching.java](https://github.com/awangdev/LintCode/blob/master/Java/Wildcard%20Matching.java)|Hard|Java|[Backtracking, DP, Greedy, String]||
|209|[Ones and Zeroes.java](https://github.com/awangdev/LintCode/blob/master/Java/Ones%20and%20Zeroes.java)|Hard|Java|[DP]||
|210|[Pow(x,n).java](https://github.com/awangdev/LintCode/blob/master/Java/Pow(x,n).java)|Medium|Java|[Binary Search, Math]||
|211|[Word Break II.java](https://github.com/awangdev/LintCode/blob/master/Java/Word%20Break%20II.java)|Review|Java|[Backtracking, DP]||
|212|[Nested List Weight Sum.java](https://github.com/awangdev/LintCode/blob/master/Java/Nested%20List%20Weight%20Sum.java)|Easy|Java|[DFS]||
|213|[Same Tree.java](https://github.com/awangdev/LintCode/blob/master/Java/Same%20Tree.java)|Easy|Java|[DFS, Tree]||
|214|[Convert Sorted Array to Binary Search Tree.java](https://github.com/awangdev/LintCode/blob/master/Java/Convert%20Sorted%20Array%20to%20Binary%20Search%20Tree.java)|Easy|Java|[DFS, Tree]||
|215|[Construct Binary Tree from Inorder and Preorder Traversal.java](https://github.com/awangdev/LintCode/blob/master/Java/Construct%20Binary%20Tree%20from%20Inorder%20and%20Preorder%20Traversal.java)|Medium|Java|[Array, DFS, Tree]||
|216|[Add Binary.java](https://github.com/awangdev/LintCode/blob/master/Java/Add%20Binary.java)|Easy|Java|[Math, String]||
|217|[Add Digits.java](https://github.com/awangdev/LintCode/blob/master/Java/Add%20Digits.java)|Easy|Java|[Math]||
|218|[Add Two Numbers.java](https://github.com/awangdev/LintCode/blob/master/Java/Add%20Two%20Numbers.java)|Medium|Java|[Linked List, Math]||
|219|[Add Two Numbers II.java](https://github.com/awangdev/LintCode/blob/master/Java/Add%20Two%20Numbers%20II.java)|Medium|Java|[Linked List]||
|220|[Balanced Binary Tree.java](https://github.com/awangdev/LintCode/blob/master/Java/Balanced%20Binary%20Tree.java)|Medium|Java|[DFS, Tree]||
|221|[Valid Anagram.java](https://github.com/awangdev/LintCode/blob/master/Java/Valid%20Anagram.java)|Easy|Java|[Hash Table, Sort]||
|222|[Populating Next Right Pointers in Each Node.java](https://github.com/awangdev/LintCode/blob/master/Java/Populating%20Next%20Right%20Pointers%20in%20Each%20Node.java)|Medium|Java|[DFS, Tree]||
|223|[Validate Binary Search Tree.java](https://github.com/awangdev/LintCode/blob/master/Java/Validate%20Binary%20Search%20Tree.java)|Medium|Java|[BST, DFS, Tree]||
|224|[Convert Sorted List to Binary Search Tree.java](https://github.com/awangdev/LintCode/blob/master/Java/Convert%20Sorted%20List%20to%20Binary%20Search%20Tree.java)|Medium|Java|[DFS, Linked List]||
|225|[Flatten Binary Tree to Linked List.java](https://github.com/awangdev/LintCode/blob/master/Java/Flatten%20Binary%20Tree%20to%20Linked%20List.java)|Medium|Java|[Binary Tree, DFS]||
|226|[Binary Tree Paths.java](https://github.com/awangdev/LintCode/blob/master/Java/Binary%20Tree%20Paths.java)|Easy|Java|[Binary Tree, DFS]||
|227|[Minimum Size Subarray Sum.java](https://github.com/awangdev/LintCode/blob/master/Java/Minimum%20Size%20Subarray%20Sum.java)|Medium|Java|[Array, Binary Search, Two Pointers]||
|228|[Clone Graph.java](https://github.com/awangdev/LintCode/blob/master/Java/Clone%20Graph.java)|Medium|Java|[BFS, DFS, Graph]||
|229|[Longest Substring Without Repeating Characters.java](https://github.com/awangdev/LintCode/blob/master/Java/Longest%20Substring%20Without%20Repeating%20Characters.java)|Medium|Java|[Hash Table, String, Two Pointers]||
|230|[Minimum Window Substring.java](https://github.com/awangdev/LintCode/blob/master/Java/Minimum%20Window%20Substring.java)|Hard|Java|[Hash Table, String, Two Pointers]||
|231|[Linked List Cycle.java](https://github.com/awangdev/LintCode/blob/master/Java/Linked%20List%20Cycle.java)|Easy|Java|[Linked List, Two Pointers]||
|232|[Remove Nth Node From End of List.java](https://github.com/awangdev/LintCode/blob/master/Java/Remove%20Nth%20Node%20From%20End%20of%20List.java)|Medium|Java|[Linked List, Two Pointers]||
|233|[Longest Substring with At Most K Distinct Characters.java](https://github.com/awangdev/LintCode/blob/master/Java/Longest%20Substring%20with%20At%20Most%20K%20Distinct%20Characters.java)|Medium|Java|[Hash Table, String]||
|234|[Linked List Cycle II.java](https://github.com/awangdev/LintCode/blob/master/Java/Linked%20List%20Cycle%20II.java)|Medium|Java|[Linked List, Two Pointers]||
|235|[Kth Smallest Number in Sorted Matrix.java](https://github.com/awangdev/LintCode/blob/master/Java/Kth%20Smallest%20Number%20in%20Sorted%20Matrix.java)|Medium|Java|[Binary Search, Heap]||
|236|[Find Minimum in Rotated Sorted Array.java](https://github.com/awangdev/LintCode/blob/master/Java/Find%20Minimum%20in%20Rotated%20Sorted%20Array.java)|Medium|Java|[Array, Binary Search]||
|237|[Find Minimum in Rotated Sorted Array II.java](https://github.com/awangdev/LintCode/blob/master/Java/Find%20Minimum%20in%20Rotated%20Sorted%20Array%20II.java)|Hard|Java|[Array, Binary Search]||
|238|[Connecting Graph.java](https://github.com/awangdev/LintCode/blob/master/Java/Connecting%20Graph.java)|Medium|Java|[Union Find]||
|239|[Connecting Graph II.java](https://github.com/awangdev/LintCode/blob/master/Java/Connecting%20Graph%20II.java)|Medium|Java|[Union Find]||
|240|[Connecting Graph III.java](https://github.com/awangdev/LintCode/blob/master/Java/Connecting%20Graph%20III.java)|Medium|Java|[Union Find]||
|241|[Number of Islands.java](https://github.com/awangdev/LintCode/blob/master/Java/Number%20of%20Islands.java)|Medium|Java|[BFS, DFS, Union Find]||
|242|[Number of Islands II.java](https://github.com/awangdev/LintCode/blob/master/Java/Number%20of%20Islands%20II.java)|Hard|Java|[Union Find]||
|243|[Graph Valid Tree.java](https://github.com/awangdev/LintCode/blob/master/Java/Graph%20Valid%20Tree.java)|Medium|Java|[BFS, DFS, Graph, Union Find]||
|244|[Surrounded Regions.java](https://github.com/awangdev/LintCode/blob/master/Java/Surrounded%20Regions.java)|Review|Java|[BFS, DFS, Union Find]||
|245|[Implement Trie.java](https://github.com/awangdev/LintCode/blob/master/Java/Implement%20Trie.java)|Medium|Java|[Design, Trie]||
|246|[Add and Search Word.java](https://github.com/awangdev/LintCode/blob/master/Java/Add%20and%20Search%20Word.java)|Medium|Java|[Backtracking, Design, Trie]||
|247|[Word Search II.java](https://github.com/awangdev/LintCode/blob/master/Java/Word%20Search%20II.java)|Hard|Java|[Backtracking, DFS, Trie]||
|248|[Word Search.java](https://github.com/awangdev/LintCode/blob/master/Java/Word%20Search.java)|Medium|Java|[Array, Backtracking]||
|249|[Word Squares.java](https://github.com/awangdev/LintCode/blob/master/Java/Word%20Squares.java)|Hard|Java|[Backtracking, Trie]||
|250|[Trapping Rain Water.java](https://github.com/awangdev/LintCode/blob/master/Java/Trapping%20Rain%20Water.java)|Hard|Java|[Array, Stack, Two Pointers]||
|251|[Trapping Rain Water II.java](https://github.com/awangdev/LintCode/blob/master/Java/Trapping%20Rain%20Water%20II.java)|Hard|Java|[BFS, Heap]||
|252|[Data Stream Median.java](https://github.com/awangdev/LintCode/blob/master/Java/Data%20Stream%20Median.java)|Hard|Java|[Design, Heap]||
|253|[Sliding Window Median.java](https://github.com/awangdev/LintCode/blob/master/Java/Sliding%20Window%20Median.java)|Hard|Java|[Design, Heap]||
|254|[Min Stack.java](https://github.com/awangdev/LintCode/blob/master/Java/Min%20Stack.java)|Easy|Java|[Design, Stack]||
|255|[Implement Queue using Stacks.java](https://github.com/awangdev/LintCode/blob/master/Java/Implement%20Queue%20using%20Stacks.java)|Easy|Java|[Design, Stack]||
|256|[Expression Expand.java](https://github.com/awangdev/LintCode/blob/master/Java/Expression%20Expand.java)|Medium|Java|[DFS, Divide and Conquer, Stack]||
|257|[Largest Rectangle in Histogram.java](https://github.com/awangdev/LintCode/blob/master/Java/Largest%20Rectangle%20in%20Histogram.java)|Hard|Java|[Array, Monotonous Stack, Stack]||
|258|[Maximum Binary Tree.java](https://github.com/awangdev/LintCode/blob/master/Java/Maximum%20Binary%20Tree.java)|Medium|Java|[Stack, Tree]||
|259|[Reverse Integer.java](https://github.com/awangdev/LintCode/blob/master/Java/Reverse%20Integer.java)|Easy|Java|[Math]||
|260|[Swap Nodes in Pairs.java](https://github.com/awangdev/LintCode/blob/master/Java/Swap%20Nodes%20in%20Pairs.java)|Medium|Java|[Linked List]||
|261|[Find Peak Element II.java](https://github.com/awangdev/LintCode/blob/master/Java/Find%20Peak%20Element%20II.java)|Hard|Java|[Binary Search, DFS, Divide and Conquer]||
|262|[Sqrt(x).java](https://github.com/awangdev/LintCode/blob/master/Java/Sqrt(x).java)|Easy|Java|[Binary Search, Math]||
|263|[First Bad Version.java](https://github.com/awangdev/LintCode/blob/master/Java/First%20Bad%20Version.java)|Easy|Java|[Binary Search]||
|264|[Wood Cut.java](https://github.com/awangdev/LintCode/blob/master/Java/Wood%20Cut.java)|Medium|Java|[Binary Search]||
|265|[Find the Duplicate Number.java](https://github.com/awangdev/LintCode/blob/master/Java/Find%20the%20Duplicate%20Number.java)|Medium|Java|[Array, Binary Search, Two Pointers]||
|266|[Palindrome Pairs.java](https://github.com/awangdev/LintCode/blob/master/Java/Palindrome%20Pairs.java)|Hard|Java|[Hash Table, String, Trie]||
|267|[Game of Life.java](https://github.com/awangdev/LintCode/blob/master/Java/Game%20of%20Life.java)|Medium|Java|[Array]||
|268|[Maximum Average Subarray II.java](https://github.com/awangdev/LintCode/blob/master/Java/Maximum%20Average%20Subarray%20II.java)|Review|Java|[Array, Binary Search]||
|269|[Meeting Rooms.java](https://github.com/awangdev/LintCode/blob/master/Java/Meeting%20Rooms.java)|Easy|Java|[Sort, Sweep Line]||
|270|[Number of Airplane in the sky.java](https://github.com/awangdev/LintCode/blob/master/Java/Number%20of%20Airplane%20in%20the%20sky.java)|Medium|Java|[Array, Interval, Sort, Sweep Line]||
|271|[Meeting Rooms II.java](https://github.com/awangdev/LintCode/blob/master/Java/Meeting%20Rooms%20II.java)|Medium|Java|[Greedy, Heap, Sort, Sweep Line]||
|272|[Building Outline.java](https://github.com/awangdev/LintCode/blob/master/Java/Building%20Outline.java)|Review|Java|[Binary Indexed Tree, Divide and Conquer, Heap, Segment Tree, Sweep Line]||
|273|[Unique Path.java](https://github.com/awangdev/LintCode/blob/master/Java/Unique%20Path.java)|Medium|Java|[Array, Coordinate DP, DP]||
|274|[Maximal Rectangle.java](https://github.com/awangdev/LintCode/blob/master/Java/Maximal%20Rectangle.java)|Hard|Java|[Array, DP, Hash Table, Stack]||
|275|[Maximal Square.java](https://github.com/awangdev/LintCode/blob/master/Java/Maximal%20Square.java)|Medium|Java|[Coordinate DP, DP]||
|276|[Longest Increasing Path in a Matrix.java](https://github.com/awangdev/LintCode/blob/master/Java/Longest%20Increasing%20Path%20in%20a%20Matrix.java)|Hard|Java|[DFS, DP, Memoization, Topological Sort]||
|277|[Coins in a Line.java](https://github.com/awangdev/LintCode/blob/master/Java/Coins%20in%20a%20Line.java)|Medium|Java|[DP, Game Theory, Greedy]||
|278|[Coins in a Line II.java](https://github.com/awangdev/LintCode/blob/master/Java/Coins%20in%20a%20Line%20II.java)|Medium|Java|[Array, DP, Game Theory, Memoization, MiniMax]||
|279|[Binary Tree Inorder Traversal.java](https://github.com/awangdev/LintCode/blob/master/Java/Binary%20Tree%20Inorder%20Traversal.java)|Easy|Java|[Hash Table, Stack, Tree]||
|280|[Binary Tree Postorder Traversal.java](https://github.com/awangdev/LintCode/blob/master/Java/Binary%20Tree%20Postorder%20Traversal.java)|Medium|Java|[Stack, Tree, Two Stacks]||
|281|[Change to Anagram.java](https://github.com/awangdev/LintCode/blob/master/Java/Change%20to%20Anagram.java)|Easy|Java|[String]||
|282|[Classical Binary Search.java](https://github.com/awangdev/LintCode/blob/master/Java/Classical%20Binary%20Search.java)|Easy|Java|[Binary Search]||
|283|[Climbing Stairs.java](https://github.com/awangdev/LintCode/blob/master/Java/Climbing%20Stairs.java)|Easy|Java|[DP, Memoization, Sequence DP]||
|284|[Coins in a Line III.java](https://github.com/awangdev/LintCode/blob/master/Java/Coins%20in%20a%20Line%20III.java)|Hard|Java|[Array, DP, Game Theory, Interval DP, Memoization]||
|285|[Closest Binary Search Tree Value.java](https://github.com/awangdev/LintCode/blob/master/Java/Closest%20Binary%20Search%20Tree%20Value.java)|Easy|Java|[BST, Binary Search, Tree]||
|286|[Compare Version Numbers.java](https://github.com/awangdev/LintCode/blob/master/Java/Compare%20Version%20Numbers.java)|Medium|Java|[String]||
|287|[Count Complete Tree Nodes.java](https://github.com/awangdev/LintCode/blob/master/Java/Count%20Complete%20Tree%20Nodes.java)|Medium|Java|[Binary Search, Tree]||
|288|[Course Schedule.java](https://github.com/awangdev/LintCode/blob/master/Java/Course%20Schedule.java)|Medium|Java|[BFS, DFS, Graph, Topological Sort]||
|289|[Course Schedule II.java](https://github.com/awangdev/LintCode/blob/master/Java/Course%20Schedule%20II.java)|Medium|Java|[BFS, DFS, Graph, Topological Sort]||
|290|[Alien Dictionary.java](https://github.com/awangdev/LintCode/blob/master/Java/Alien%20Dictionary.java)|Hard|Java|[BFS, Backtracking, DFS, Graph, Topological Sort]||
|291|[Binary Tree Preorder Traversal.java](https://github.com/awangdev/LintCode/blob/master/Java/Binary%20Tree%20Preorder%20Traversal.java)|Easy|Java|[BFS, DFS, Stack, Tree]||
|292|[Closest Number in Sorted Array.java](https://github.com/awangdev/LintCode/blob/master/Java/Closest%20Number%20in%20Sorted%20Array.java)|Easy|Java|[Binary Search]||
|293|[Complete Binary Tree.java](https://github.com/awangdev/LintCode/blob/master/Java/Complete%20Binary%20Tree.java)|Easy|Java|[BFS, DFS, Tree]||
|294|[Compare Strings.java](https://github.com/awangdev/LintCode/blob/master/Java/Compare%20Strings.java)|Easy|Java|[String]||
|295|[Contains Duplicate.java](https://github.com/awangdev/LintCode/blob/master/Java/Contains%20Duplicate.java)|Easy|Java|[Array, Hash Table]||
|296|[Contains Duplicate II.java](https://github.com/awangdev/LintCode/blob/master/Java/Contains%20Duplicate%20II.java)|Easy|Java|[Array, Hash Table]||
|297|[Contains Duplicate III.java](https://github.com/awangdev/LintCode/blob/master/Java/Contains%20Duplicate%20III.java)|Medium|Java|[BST]||
|298|[Burst Balloons.java](https://github.com/awangdev/LintCode/blob/master/Java/Burst%20Balloons.java)|Hard|Java|[DP, Divide and Conquer, Interval DP, Memoization]||
|299|[Nim Game.java](https://github.com/awangdev/LintCode/blob/master/Java/Nim%20Game.java)|Easy|Java|[Brainteaser, DP, Game Theory]||
|300|[Convert Integer A to Integer B.java](https://github.com/awangdev/LintCode/blob/master/Java/Convert%20Integer%20A%20to%20Integer%20B.java)|Easy|Java|[Bit Manipulation]||
|301|[Cosine Similarity.java](https://github.com/awangdev/LintCode/blob/master/Java/Cosine%20Similarity.java)|Easy|Java|[Basic Implementation]||
|302|[Count 1 in Binary.java](https://github.com/awangdev/LintCode/blob/master/Java/Count%201%20in%20Binary.java)|Easy|Java|[Bit Manipulation]||
|303|[Count and Say.java](https://github.com/awangdev/LintCode/blob/master/Java/Count%20and%20Say.java)|Easy|Java|[Basic Implementation, String]||
|304|[One Edit Distance.java](https://github.com/awangdev/LintCode/blob/master/Java/One%20Edit%20Distance.java)|Medium|Java|[String]||
|305|[K Edit Distance.java](https://github.com/awangdev/LintCode/blob/master/Java/K%20Edit%20Distance.java)|Hard|Java|[DP, Double Sequence DP, Trie]||
|306|[Jump Game.java](https://github.com/awangdev/LintCode/blob/master/Java/Jump%20Game.java)|Medium|Java|[Array, DP, Greedy]||
|307|[Coin Change 2.java](https://github.com/awangdev/LintCode/blob/master/Java/Coin%20Change%202.java)|Medium|Java|[DP, Sequence DP]||
|308|[Paint House.java](https://github.com/awangdev/LintCode/blob/master/Java/Paint%20House.java)|Easy|Java|[DP, Sequence DP]||
|309|[Decode Ways.java](https://github.com/awangdev/LintCode/blob/master/Java/Decode%20Ways.java)|Medium|Java|[DP, Partition DP, String]||
|310|[Longest Continuous Increasing Subsequence.java](https://github.com/awangdev/LintCode/blob/master/Java/Longest%20Continuous%20Increasing%20Subsequence.java)|Easy|Java|[Array, Coordinate DP, DP]||
|311|[Minimum Path Sum.java](https://github.com/awangdev/LintCode/blob/master/Java/Minimum%20Path%20Sum.java)|Medium|Java|[Array, Coordinate DP, DP]||
|312|[Counting Bits.java](https://github.com/awangdev/LintCode/blob/master/Java/Counting%20Bits.java)|Medium|Java|[Bit Manipulation, Bitwise DP, DP]||
|313|[Continuous Subarray Sum.java](https://github.com/awangdev/LintCode/blob/master/Java/Continuous%20Subarray%20Sum.java)|Medium|Java|[Coordinate DP, DP, Math]||
|314|[House Robber.java](https://github.com/awangdev/LintCode/blob/master/Java/House%20Robber.java)|Easy|Java|[DP, Sequence DP]||
|315|[House Robber II.java](https://github.com/awangdev/LintCode/blob/master/Java/House%20Robber%20II.java)|Medium|Java|[DP, Sequence DP]||
|316|[House Robber III.java](https://github.com/awangdev/LintCode/blob/master/Java/House%20Robber%20III.java)|Medium|Java|[DFS, DP, Status DP, Tree]||
|317|[Paint House II.java](https://github.com/awangdev/LintCode/blob/master/Java/Paint%20House%20II.java)|Hard|Java|[DP, Sequence DP]||
|318|[Best Time to Buy and Sell Stock I.java](https://github.com/awangdev/LintCode/blob/master/Java/Best%20Time%20to%20Buy%20and%20Sell%20Stock%20I.java)|Easy|Java|[Array, DP, Sequence DP]||
|319|[Best Time to Buy and Sell Stock II.java](https://github.com/awangdev/LintCode/blob/master/Java/Best%20Time%20to%20Buy%20and%20Sell%20Stock%20II.java)|Easy|Java|[Array, DP, Greedy, Sequence DP]||
|320|[Best Time to Buy and Sell Stock III .java](https://github.com/awangdev/LintCode/blob/master/Java/Best%20Time%20to%20Buy%20and%20Sell%20Stock%20III%20.java)|Hard|Java|[Array, DP, Sequence DP]||
|321|[Best Time to Buy and Sell Stock IV.java](https://github.com/awangdev/LintCode/blob/master/Java/Best%20Time%20to%20Buy%20and%20Sell%20Stock%20IV.java)|Hard|Java|[DP, Sequence DP]||
|322|[Russian Doll Envelopes.java](https://github.com/awangdev/LintCode/blob/master/Java/Russian%20Doll%20Envelopes.java)|Hard|Java|[Binary Search, Coordinate DP, DP]||
|323|[Jump Game II.java](https://github.com/awangdev/LintCode/blob/master/Java/Jump%20Game%20II.java)|Hard|Java|[Array, Coordinate DP, DP, Greedy]||
|324|[Palindrome Partitioning.java](https://github.com/awangdev/LintCode/blob/master/Java/Palindrome%20Partitioning.java)|Medium|Java|[Backtracking, DFS]||
|325|[Permutation in String.java](https://github.com/awangdev/LintCode/blob/master/Java/Permutation%20in%20String.java)|Medium|Java|[Two Pointers]||
|326|[Permutations II.java](https://github.com/awangdev/LintCode/blob/master/Java/Permutations%20II.java)|Medium|Java|[Backtracking]||
|327|[Shuffle an Array.java](https://github.com/awangdev/LintCode/blob/master/Java/Shuffle%20an%20Array.java)|Medium|Java|[Permutation]||
|328|[Find All Anagrams in a String.java](https://github.com/awangdev/LintCode/blob/master/Java/Find%20All%20Anagrams%20in%20a%20String.java)|Easy|Java|[Hash Table]||
|329|[Group Anagrams.java](https://github.com/awangdev/LintCode/blob/master/Java/Group%20Anagrams.java)|Medium|Java|[Hash Table, String]||
|330|[Backpack.java](https://github.com/awangdev/LintCode/blob/master/Java/Backpack.java)|Medium|Java|[Backpack DP, DP]||
|331|[Backpack II.java](https://github.com/awangdev/LintCode/blob/master/Java/Backpack%20II.java)|Medium|Java|[Backpack DP, DP]||
|332|[Backpack V.java](https://github.com/awangdev/LintCode/blob/master/Java/Backpack%20V.java)|Medium|Java|[Backpack DP, DP]||
|333|[Count Primes.java](https://github.com/awangdev/LintCode/blob/master/Java/Count%20Primes.java)|Easy|Java|[Hash Table, Math]||
|334|[Delete Node in a Linked List.java](https://github.com/awangdev/LintCode/blob/master/Java/Delete%20Node%20in%20a%20Linked%20List.java)|Easy|Java|[Linked List]||
|335|[Excel Sheet Column Number.java](https://github.com/awangdev/LintCode/blob/master/Java/Excel%20Sheet%20Column%20Number.java)|Easy|Java|[Math]||
|336|[Excel Sheet Column Title.java](https://github.com/awangdev/LintCode/blob/master/Java/Excel%20Sheet%20Column%20Title.java)|Easy|Java|[Math]||
|337|[Flip Game.java](https://github.com/awangdev/LintCode/blob/master/Java/Flip%20Game.java)|Easy|Java|[String]||
|338|[Flip Game II.java](https://github.com/awangdev/LintCode/blob/master/Java/Flip%20Game%20II.java)|Review|Java|[DFS, backtracking]||
|339|[Expression Tree Build.java](https://github.com/awangdev/LintCode/blob/master/Java/Expression%20Tree%20Build.java)|Hard|Java|[Binary Tree, Expression Tree, Stack]||
|340|[Expression Evaluation.java](https://github.com/awangdev/LintCode/blob/master/Java/Expression%20Evaluation.java)|Hard|Java|[Binary Tree, DFS, Expression Tree, Stack]||
|341|[Convert Expression to Polish Notation.java](https://github.com/awangdev/LintCode/blob/master/Java/Convert%20Expression%20to%20Polish%20Notation.java)|Hard|Java|[Binary Tree, DFS, Expression Tree, Stack]||
|342|[Convert Expression to Reverse Polish Notation.java](https://github.com/awangdev/LintCode/blob/master/Java/Convert%20Expression%20to%20Reverse%20Polish%20Notation.java)|Hard|Java|[Binary Tree, DFS, Expression Tree, Stack]||
|343|[Evaluate Reverse Polish Notation.java](https://github.com/awangdev/LintCode/blob/master/Java/Evaluate%20Reverse%20Polish%20Notation.java)|Medium|Java|[Stack]||
|344|[Decode Ways II.java](https://github.com/awangdev/LintCode/blob/master/Java/Decode%20Ways%20II.java)|Hard|Java|[DP, Partition DP]||
|345|[Palindrome Partitioning II.java](https://github.com/awangdev/LintCode/blob/master/Java/Palindrome%20Partitioning%20II.java)|Hard|Java|[DP, Partition DP]||
|346|[Backpack III.java](https://github.com/awangdev/LintCode/blob/master/Java/Backpack%20III.java)|Hard|Java|[Backpack DP, DP]||
|347|[First Missing Positive.java](https://github.com/awangdev/LintCode/blob/master/Java/First%20Missing%20Positive.java)|Hard|Java|[Array]||
|348|[Gas Station.java](https://github.com/awangdev/LintCode/blob/master/Java/Gas%20Station.java)|Medium|Java|[Greedy]||
|349|[Implement strStr().java](https://github.com/awangdev/LintCode/blob/master/Java/Implement%20strStr().java)|Easy|Java|[String, Two Pointers]||
|350|[Insertion Sort List.java](https://github.com/awangdev/LintCode/blob/master/Java/Insertion%20Sort%20List.java)|Medium|Java|[Linked List, Sort]||
|351|[Integer to English Words.java](https://github.com/awangdev/LintCode/blob/master/Java/Integer%20to%20English%20Words.java)|Hard|Java|[Math, String]||
|352|[Interleaving Positive and Negative Numbers.java](https://github.com/awangdev/LintCode/blob/master/Java/Interleaving%20Positive%20and%20Negative%20Numbers.java)|Medium|Java|[Two Pointers]||
|353|[Largest Number.java](https://github.com/awangdev/LintCode/blob/master/Java/Largest%20Number.java)|Medium|Java|[Sort]||
|354|[Last Position of Target.java](https://github.com/awangdev/LintCode/blob/master/Java/Last%20Position%20of%20Target.java)|Easy|Java|[Binary Search]||
|355|[Length of Last Word.java](https://github.com/awangdev/LintCode/blob/master/Java/Length%20of%20Last%20Word.java)|Easy|Java|[String]||
|356|[Longest Common Substring.java](https://github.com/awangdev/LintCode/blob/master/Java/Longest%20Common%20Substring.java)|Medium|Java|[DP, Double Sequence DP, String]||
|357|[Longest Consecutive Sequence.java](https://github.com/awangdev/LintCode/blob/master/Java/Longest%20Consecutive%20Sequence.java)|Medium|Java|[Array, Hash Table]||
|358|[Longest Increasing Continuous subsequence.java](https://github.com/awangdev/LintCode/blob/master/Java/Longest%20Increasing%20Continuous%20subsequence.java)|Easy|Java|[Array, Coordinate DP, DP]||
|359|[Longest Increasing Continuous subsequence II.java](https://github.com/awangdev/LintCode/blob/master/Java/Longest%20Increasing%20Continuous%20subsequence%20II.java)|Medium|Java|[Array, Coordinate DP, DP, Memoization]||
|360|[N-Queens.java](https://github.com/awangdev/LintCode/blob/master/Java/N-Queens.java)|Hard|Java|[Backtracking]||
|361|[N-Queens II.java](https://github.com/awangdev/LintCode/blob/master/Java/N-Queens%20II.java)|Hard|Java|[Backtracking]||
|362|[Longest Words.java](https://github.com/awangdev/LintCode/blob/master/Java/Longest%20Words.java)|Easy|Java|[Hash Map, String]||
|363|[Maximum Subarray.java](https://github.com/awangdev/LintCode/blob/master/Java/Maximum%20Subarray.java)|Easy|Java|[Array, DP, Divide and Conquer, Sequence DP]||
|364|[Maximum Subarray II.java](https://github.com/awangdev/LintCode/blob/master/Java/Maximum%20Subarray%20II.java)|Medium|Java|[Array, DP, Greedy, Sequence DP]||
|365|[Median.java](https://github.com/awangdev/LintCode/blob/master/Java/Median.java)|Easy|Java|[Array, Quick Select, Quick Sort]||
|366|[Merge Sorted Array.java](https://github.com/awangdev/LintCode/blob/master/Java/Merge%20Sorted%20Array.java)|Easy|Java|[Array, Two Pointers]||
|367|[Middle of Linked List.java](https://github.com/awangdev/LintCode/blob/master/Java/Middle%20of%20Linked%20List.java)|Easy|Java|[Linked List]||
|368|[Singleton.java](https://github.com/awangdev/LintCode/blob/master/Java/Singleton.java)|Easy|Java|[Design]||
|369|[Remove Linked List Elements.java](https://github.com/awangdev/LintCode/blob/master/Java/Remove%20Linked%20List%20Elements.java)|Easy|Java|[Linked List]||
|370|[Fibonacci.java](https://github.com/awangdev/LintCode/blob/master/Java/Fibonacci.java)|Easy|Java|[DP, Math, Memoization]||
|371|[Palindrome Linked List.java](https://github.com/awangdev/LintCode/blob/master/Java/Palindrome%20Linked%20List.java)|Easy|Java|[Linked List, Two Pointers]||
|372|[Reverse Linked List.java](https://github.com/awangdev/LintCode/blob/master/Java/Reverse%20Linked%20List.java)|Easy|Java|[Linked List]||
|373|[Reverse Linked List II .java](https://github.com/awangdev/LintCode/blob/master/Java/Reverse%20Linked%20List%20II%20.java)|Medium|Java|[Linked List]||
|374|[Palindrome Permutation.java](https://github.com/awangdev/LintCode/blob/master/Java/Palindrome%20Permutation.java)|Easy|Java|[Hash Table]||
|375|[Valid Palindrome.java](https://github.com/awangdev/LintCode/blob/master/Java/Valid%20Palindrome.java)|Easy|Java|[String, Two Pointers]||
|376|[Implement Stack using Queues.java](https://github.com/awangdev/LintCode/blob/master/Java/Implement%20Stack%20using%20Queues.java)|Easy|Java|[Design, Stack]||
|377|[Implement Stack.java](https://github.com/awangdev/LintCode/blob/master/Java/Implement%20Stack.java)|Easy|Java|[Stack]||
|378|[Invert Binary Tree.java](https://github.com/awangdev/LintCode/blob/master/Java/Invert%20Binary%20Tree.java)|Easy|Java|[BFS, DFS, Tree]||
|379|[Maximum Depth of Binary Tree.java](https://github.com/awangdev/LintCode/blob/master/Java/Maximum%20Depth%20of%20Binary%20Tree.java)|Easy|Java|[DFS, Tree]||
|380|[Minimum Depth of Binary Tree.java](https://github.com/awangdev/LintCode/blob/master/Java/Minimum%20Depth%20of%20Binary%20Tree.java)|Easy|Java|[BFS, DFS, Tree]||
|381|[Symmetric Tree.java](https://github.com/awangdev/LintCode/blob/master/Java/Symmetric%20Tree.java)|Easy|Java|[BFS, DFS, Tree]||
|382|[Merge Two Binary Trees.java](https://github.com/awangdev/LintCode/blob/master/Java/Merge%20Two%20Binary%20Trees.java)|Easy|Java|[DFS, Tree]||
|383|[Subtree.java](https://github.com/awangdev/LintCode/blob/master/Java/Subtree.java)|Easy|Java|[DFS, Tree]||
|384|[Lowest Common Ancestor of a Binary Tree.java](https://github.com/awangdev/LintCode/blob/master/Java/Lowest%20Common%20Ancestor%20of%20a%20Binary%20Tree.java)|Medium|Java|[DFS, Tree]||
|385|[Lowest Common Ancestor II.java](https://github.com/awangdev/LintCode/blob/master/Java/Lowest%20Common%20Ancestor%20II.java)|Easy|Java|[Hash Table, Tree]||
|386|[Lowest Common Ancestor of a Binary Search Tree.java](https://github.com/awangdev/LintCode/blob/master/Java/Lowest%20Common%20Ancestor%20of%20a%20Binary%20Search%20Tree.java)|Medium|Java|[BST, DFS, Tree]||
|387|[Merge Intervals.java](https://github.com/awangdev/LintCode/blob/master/Java/Merge%20Intervals.java)|Medium|Java|[Array, Sort, Sweep Line]||
|388|[Hash Function.java](https://github.com/awangdev/LintCode/blob/master/Java/Hash%20Function.java)|Easy|Java|[Hash Table]||
|389|[Merge Two Sorted Lists.java](https://github.com/awangdev/LintCode/blob/master/Java/Merge%20Two%20Sorted%20Lists.java)|Easy|Java|[Linked List]||
|390|[Missing Number.java](https://github.com/awangdev/LintCode/blob/master/Java/Missing%20Number.java)|Easy|Java|[Array, Bit Manipulation, Math]||
|391|[LRU Cache.java](https://github.com/awangdev/LintCode/blob/master/Java/LRU%20Cache.java)|Hard|Java|[Design, Hash Table, Linked List]||
|392|[Remove Duplicates from Sorted Array.java](https://github.com/awangdev/LintCode/blob/master/Java/Remove%20Duplicates%20from%20Sorted%20Array.java)|Easy|Java|[Array, Two Pointers]||
|393|[Remove Duplicates from Sorted Array II.java](https://github.com/awangdev/LintCode/blob/master/Java/Remove%20Duplicates%20from%20Sorted%20Array%20II.java)|Medium|Java|[Array, Two Pointers]||
|394|[Remove Duplicates from Sorted List.java](https://github.com/awangdev/LintCode/blob/master/Java/Remove%20Duplicates%20from%20Sorted%20List.java)|Easy|Java|[Linked List]||
|395|[Remove Duplicates from Sorted List II.java](https://github.com/awangdev/LintCode/blob/master/Java/Remove%20Duplicates%20from%20Sorted%20List%20II.java)|Medium|Java|[Linked List]||
|396|[QuickSort.java](https://github.com/awangdev/LintCode/blob/master/Java/QuickSort.java)|Medium|Java|[Sort]||
|397|[MergeSort.java](https://github.com/awangdev/LintCode/blob/master/Java/MergeSort.java)|Medium|Java|[Sort]||
|398|[Longest Word in Dictionary.java](https://github.com/awangdev/LintCode/blob/master/Java/Longest%20Word%20in%20Dictionary.java)|Easy|Java|[Hash Table, Trie]||
|399|[Anagrams.java](https://github.com/awangdev/LintCode/blob/master/Java/Anagrams.java)|Medium|Java|[Array, Hash Map]||
|400|[Binary Tree Level Order Traversal.java](https://github.com/awangdev/LintCode/blob/master/Java/Binary%20Tree%20Level%20Order%20Traversal.java)|Medium|Java|[BFS, DFS, Tree]||
|401|[Binary Tree Level Order Traversal II.java](https://github.com/awangdev/LintCode/blob/master/Java/Binary%20Tree%20Level%20Order%20Traversal%20II.java)|Medium|Java|[BFS, Tree]||
|402|[Binary Tree Longest Consecutive Sequence II.java](https://github.com/awangdev/LintCode/blob/master/Java/Binary%20Tree%20Longest%20Consecutive%20Sequence%20II.java)|Medium|Java|[DFS, Divide and Conquer, Double Recursive, Tree]||
|403|[Binary Tree Maximum Path Sum.java](https://github.com/awangdev/LintCode/blob/master/Java/Binary%20Tree%20Maximum%20Path%20Sum.java)|Hard|Java|[DFS, Tree]||
|404|[Path Sum.java](https://github.com/awangdev/LintCode/blob/master/Java/Path%20Sum.java)|Easy|Java|[DFS, Tree]||
|405|[Path Sum II.java](https://github.com/awangdev/LintCode/blob/master/Java/Path%20Sum%20II.java)|Easy|Java|[Backtracking, DFS, Tree]||
|406|[Path Sum III.java](https://github.com/awangdev/LintCode/blob/master/Java/Path%20Sum%20III.java)|Easy|Java|[DFS, Double Recursive, Tree]||
|407|[Rotate String.java](https://github.com/awangdev/LintCode/blob/master/Java/Rotate%20String.java)|Easy|Java|[String]||
|408|[Path Sum IV.java](https://github.com/awangdev/LintCode/blob/master/Java/Path%20Sum%20IV.java)|Medium|Java|[DFS, Hash Map, Tree]||