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([email protected]), 或者在GitHub上发issue给我.

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