Yeening / LeetCode

Solutions&notes of LeeCode problems in Java, C++ and Python

LeetCode

LeetCode solutions in C++, Java and Python3.

x	NO.	Title	Solution	Note	Difficulty	Tag
1	1	Two Sum	C++ PythonJava	Note	Easy	Hash table
2	2	Add Two Numbers	C++ PythonJava	Note	Medium	Linked List
3	3	Longest Substring Without Repeating Characters 2	C++ PythonJava	Note	Medium	Hash Table
4	15	3Sum 2	Java	Note	Medium	Array Two Pointers
5	18	4Sum 2	Java	Note 2	Medium	Array Two Pointers
6	454	4Sum II 2	Java	Note	Medium	Hash table``Binary Search
7	19	Remove Nth Node From End of List 3	C++ Python Java	Note	Medium	Linked List
8	206	Reverse Linked List 2	C++ Python Java	Note	Easy	LinkedList
9	21	Merge_Two_Sorted_Lists	Java	Note	Easy	Linked List
10	20	Valid_Parentheses 2	Java	Note	Easy	Stack
11	5	Longest Palindromic Substring	Java	Note	Medium	Dynamic Programming
12	32	Longest Valid Parentheses 2	Java	Note	Hard	Dynamic Programming
13	120	Triangle	Java	Note	Medium	Dynamic Programming
14	62	Unique Paths	C++ Python Java	Note	Medium	Dynamic Programming
15	96	Unique Binary Search Trees 2	C++ Python Java	Note	Medium	Dynamic Programming
16	95	Unique Binary Search Trees II	Java	Note	Medium	Dynamic Programming
17	63	Unique Paths II 2	Java	Note	Medium	Dynamic Programming
18	280	Wiggle Sort	Java	Note	Medium	Sort
19	136	Single Number	C++ Python Java	Note	Easy	Bit Manipulation
20	266	Palindrome Permutation	Java	Note	Easy	Hash Table
21	293	Flip Game	Java	Note	Easy	String
22	226	Invert Binary Tree	Java	Note	Easy	Tree
23	260	Single Number III	Java	Note	Medium	Bit Manipulation
24	94	Binary Tree Inorder Traversal	C++ Python Java	Note	Medium	Tree
25	144	Binary Tree Preorder Traversal	Java	Note	Medium	Tree
26	292	Nim Game	C++ Python Java	Note	Easy	Brainteaser
27	182	Duplicate Emails	SQL	Note	Easy	SQL
28	238	Product of Array Except Self	Java	Note	Medium	Array
29	237	Delete Node in a Linked List	Java		Easy	Linked List
30	283	Move Zeroes 2	Java		Easy	Two pointers
31	258	Add Digits	Java	Note	Easy	Math
32	202	Happy Number 3	Java	Note	Easy	Math Hash Table
33	264	Ugly Number II	Java	Note	Medium	Math Heap
34	263	Ugly Number	Java		Easy	Math
35	78	Subsets 2	Java	Note	Medium	Backtracking
36	90	Subsets II	Java	Note	Medium	Backtracking
37	51	N-Queens	Java	Note	Hard	Backtracking
38	52	N-Queens II	Java	Note	Hard	Backtracking
39	22	Generate Parentheses 2	C++PythonJava	Note	Medium	Backtracking
40	39	Combination Sum	Java Python	Note	Medium	Backtracking
41	46	Permutations 3	C++ Python Java	Note	Medium	Backtracking
42	47	Permutations II	Java	Note	Medium	Backtracking
43	33	Search in Rotated Sorted Array 2	C++ Python Java	Note	Medium	Binary Search
44	34	Search for a Range 5	C++ Python Java	Note	Medium	Binary Search
45	49	Group Anagrams	C++ Python Java	Note	Medium	Hash Table
46	297	Serialize and Deserialize Binary Tree 4	C++ Python Java	Note	Hard	Tree
47	4	Median of Two Sorted Arrays 2	C++ Python Java	Note	Hard	Tree
48	175	Combine Two Tables	SQL		Easy	SQL
49	169	Majority Element 2	Java		Easy	Array
50	242	Valid Anagram 2	Java		Easy	Hash Table
51	230	Kth Smallest Element in a BST 3	Java		Medium	Tree Binary Search
52	217	Contains Duplicate	Java		Easy	Hash Table
53	219	Contains Duplicate II	Java		Easy	Hash Table
54	14	Longest Common Prefix	Java		Easy	String
55	13	Roman to Integer	Java	Note	Easy	String Math
56	912	Sort an array	Java	Note	Medium	Sorting
57	12	Intger to Roman	Java	Note	Medium	String Math
58	38	Count and Say	Java		Easy	String
59	7	Reverse Integer	Java	Note	Easy	Math
60	9	Palindrome Number	Java	Note	Easy	Math
61	26	Remove_Duplicates_from_Sorted_Array	Java	Note	Easy	Two Pointers
62	27	Remove Element	Java	Note	Easy	Two Pointers
63	35	Search Insert Position	Java	Note	Easy	Binary Search
64	58	Length of Last Word	Java	Note	Easy	String
65	67	Add Binary	Java		Easy	Math
66	66	Plus One	Java		Easy	Math
67	69	Sqrt(x) 2	Java		Easy	Binary Search
68	70	CLimbing Stairs	Java		Easy	Dynamic Programming
69	54	Spiral Matrix	Java	Note	Medium	Array
70	100	Same Tree	Java		Easy	Tree
71	56	Merge Intervals 3	Java	Note	Medium	Sorting
72	101	Symmetric Tree 2	Java		Easy	Tree
73	102	Binary Tree Level Order Traversal	Java		Medium	Tree BFS
74	23	Merge k Sorted Lists 2	Java	Note	Hard	Divide and Conquer
75	103	Binary Tree Zigzag Level Order Traversal	Java 2	Note	Medium	Tree
76	572	Subtree of Another Tree	Java	Note	Easy	Tree
77	107	Binary_Tree_Level_Order_Traversal_II	Java		Easy	Tree
78	176	Second Highest Salary	Sql		Easy	SQL
79	177	Nth Highest Salary	Sql		Medium	SQL
80	829	Consecutive Numbers Sum	Java	Note	Hard	Math
81	239	Sliding Window Maximum 3	Java	Note	Hard	Sliding Window
82	76	Minimum Window Substring 2	Java C++	Note	Hard	Sliding Window Hash Table Two Pointers
83	713	Subarray Product Less Than K	Java C++	Note	Medium	Two Pointers
84	992	Subarrays with K Different Integers	Java	Note	Hard	Sliding Window Two Pointers
85	516	Longest Palindromic Subsequence 3	Java		Medium	Dynamic Programming
86	974	Subarray Sums Divisible by K	Java	Note	Medium	Hash Table
87	945	Minimum Increment to Make Array Unique 2	Java	Note	Medium	Array
88	42	Trapping Rain Water 3	Java	Note	Hard	Two Pointers
89	99	Recover Binary Search Tree	Java	Note	Hard	Tree
90	124	Binary Tree Maximum Path Sum 2	Java Cpp	Note	Hard	Tree
91	127	Word Ladder	Java	Note	Medium	BFS
92	138	Copy List with Random Pointer 2	Java	Note	Medium	Linked List
93	139	Word Break 2	Java		Medium	Dynamic Programming
94	146	LRU Cache	Java 2	Note	Medium	Design
95	200	Number of Islands 2	Java		Medium	DFS
96	201	Word Search II	Java	Note	Hard	Trie Backtracking
97	240	Search a 2D Matrix II 3	Java		Medium	Divide and Conquer
98	253	Meeting Rooms II 2	Java	Note	Medium	Heap Greedy
99	273	Integer to English Words	Java		Hard	Math
100	295	Find Median from Data Stream 3	Java	Note	Hard	Design Heap
101	1192	Critical Connections in a Network	Java	Note	Hard	DFS
102	937	Reorder Data in Log Files 2	Java		Easy	String
103	642	Design Search Autocomplete System	Java	Note	Hard	Design Trie
104	252	Meeting Rooms	Java		Easy	Sort
105	323	Number of Connected Components in an Undirected Graph	Java	Note	Medium	DFS Union Find
106	347	Top K Frequent Elements 2	Java		Medium	Heap
107	735	Asteroid Collision	Java	Note	Medium	Stack
108	121	Best Time to Buy and Sell Stock	Java		Easy	Array
109	994	Rotting Oranges	Java		Easy	BFS
110	981	Time Based Key-Value Store	Java	Note	Medium	Hash Table
111	692	Top K Frequent Words 2	Java		Medium	Heap
112	380	Insert Delete GetRandom O(1) 4	Java	Note	Medium	Hash Table Design
113	953	Verifying an Alien Dictionary	Java		Easy	Hash Table
114	269	Alien Dictionary	Java		Hard	Topological Sort
115	79	Word Search 2	Java		Medium	Backtracking
116	224	Basic Calculator 2	Java	Note	Hard	Math Stack
117	227	Basic Calculator II 2	Java		Medium	String
118	1462	Course Schedule IV	Java		Medium	Graph
119	11	Container With Most Water 2	Java	Note	Medium	Two Pointers
120	16	3Sum Closest 3	Java		Medium	Two Pointers
121	28	Implemant strStr()	Java		Easy	Two Pointers
122	48	Rotate Image	Java 2		Medium	Array
123	165	Compare Version Numbers	Java		Medium	String
124	268	Missing Number	Java		Easy	Math
125	387	First Unique Character in a String 2	Java		Easy	Hash Table
126	819	Most Common Word	Java		Easy	Hash Table
127	98	Validate Binary Search Tree	Java 2		Medium	Tree
128	675	Cut Off Trees for Golf Event	Java		Hard	BFS
129	236	Lowest Common Ancestor of a Binary Tree 2	Java		Medium	Tree
130	543	Diameter of Binary Tree 2	Java		Easy	Tree
131	207	Course Schedule	Java 2		Medium	DFS
132	733	Flood Fill	Java		Easy	DFS
133	17	Letter Combinations of a Phone Number	Java		Medium	Back Tracking
134	348	Design Tic-Tac-Toe 2	Java		Medium	Design
135	155	Min Stack	Java 2		Easy	Design
136	895	Maximum Frequency Stack 2	Java		Hard	Design
137	763	Partition Labels	Java		Medium	Two pointers
138	957	Prison Cells After N Days	Java		Medium	Hash Table
139	349	Intersection of Two Arrays	Java		Easy	Hash Table
140	350	Intersection of Two Arrays II	Java		Easy	Hash Table
141	36	Valid Sudoku	Java		Medium	Hash Table
142	344	Reverse String	Java		Easy	Two pointers
143	125	Valid Palindrome	Java		Easy	Two pointers
144	8	String to Integer (atoi)	Java		Medium	String
145	234	Palindrome Linked List 2	Java		Easy	Linked List
146	141	Linked List Cycle	Java		Easy	Linked List
147	104	Maximum Depth of Binary Tree	Java		Easy	Tree
148	108	Convert Sorted Array to Binary Search Tree	Java		Easy	Tree
149	88	Merge Sorted Array	Java		Easy	Two pointers
150	278	First Bad Version	Java		Easy	Binary Search
151	53	Maximum Subarray	Java		Easy	Array
152	198	House Robber	Java		Easy	DP
153	384	Shuffle an Array	Java		Medium	Design
154	412	Fizz Buzz	Java		Easy	Math
155	204	Count Primes 2	Java		Easy	Math
156	326	Power of Three	Java		Easy	Math
157	191	Number of 1 Bits	Java		Easy	Bit
158	461	Hamming Distance	Java		Easy	Bit
159	190	Reverse Bits	Java		Easy	Bit
160	118	Pascal's Triangle	Java		Easy	Array
161	119	Pascal's Triangle II	Java		Easy	Array
162	213	House Robber II 2	Java		Medium	Dynamic Programming
163	337	House Robber III 2	Java		Medium	DFS
164	73	Set Matrix Zeroes	Java		Medium	Array
165	334	Increasing Triplet Subsequence	Java		Medium	Array
166	163	Missing Ranges	Java		Medium	Array
167	160	Intersection of Two Linked Lists	Java		Easy	Linked List
168	328	Odd Even Linked List	Java		Medium	Linked List
169	105	Construct Binary Tree from Preorder and Inorder Traversal	Java		Medium	Tree
170	116	Populating Next Right Pointers in Each Node	Java		Medium	Tree
171	117	Populating Next Right Pointers in Each Node II	Java		Medium	Tree
172	285	Inorder Successor in BST	Java		Medium	Tree
173	75	Sort Colors	Java		Medium	Two pointers
174	251	Flatten 2D Vector	Java		Medium	Design
175	300	Longest Increasing Subsequence 3	Java		Medium	Binary Search
176	322	Coin Change	Java		Medium	Dynamic Programming
177	55	Jump Game	Java		Medium	Dynamic Programming
178	162	Find Peak Element	Java		Medium	Binary Search
179	215	Kth Largest Element in an Array	Java		Medium	Divide and Conquer
180	171	Excel Sheet Column Number	Java		Easy	Math
181	172	Factorial Trailing Zeroes	Java		Easy	Math
182	50	Pow(x, n)	Java		Medium	Math
183	29	Divide Two Integers	Java		Medium	Math
184	166	Fraction to Recurring Decimal	Java		Medium	Math
185	150	Evaluate Reverse Polish Notation	Java		Medium	Stack
186	277	Find the Celebrity	Java		Medium	Array
187	621	Task Scheduler	Java		Medium	Array
188	289	Game of Life	Java		Medium	Array
189	41	First Missing Positive	Java 2		Hard	Array
190	930	Binary Subarrays With Sum 2	Java		Medium	Prefix Sum
191	523	Continuous Subarray Sum	Java		Medium	Prefix Sum
192	1314	Matrix Block Sum	Java		Medium	Prefix Sum
193	208	Implement Trie (Prefix Tree)	Java		Medium	Trie
194	706	Design HashMap	Java		Easy	Hash Map
195	152	Maximum Product Subarray	Java		Medium	DP
196	151	Reverse Words in a String	Java		Medium	String
197	140	Word Break II	Java		Hard	Back tracking
198	210	Course Schedule II 3	Java		Medium	Topological Sort
199	1041	Robot Bounded In Circle	Java		Medium	Math
200	221	Maximal Square	Java		Medium	Dynamic Programming
201	973	K Closest Points to Origin 2	Java		Medium	Divide and Conquer
202	1010	Pairs of Songs With Total Durations Divisible by 60	Java		Medium	Array
203	1465	Maximum Area of a Piece of Cake After Horizontal and Vertical Cuts	Java		Medium	Array
204	547	Number of Provinces 2	Java		Medium	Union find DFS
205	114	Flatten Binary Tree to Linked List	Java		Medium	Tree
206	106	Construct Binary Tree from Inorder and Postorder Traversal	Java		Medium	Tree
207	652	Find Duplicate Subtrees 2	Java		Medium	Tree
208	538	Convert BST to Greater Tree	Java		Medium	Tree
209	701	Insert into a Binary Search Tree	Java		Medium	BST
210	450	Delete Node in a BST	Java		Medium	BST
211	797	All Paths From Source to Target	Java		Medium	DFS
212	1373	Maximum Sum BST in Binary Tree	Java		Hard	BST
213	341	Flatten Nested List Iterator	Java		Medium	Design
214	222	Count Complete Tree Nodes	Java		Medium	Tree
215	92	Reverse Linked List II	Java		Medium	Linked List
216	25	Reverse Nodes in k-Group	Java		Hard	Linked List
217	931	Minimum Falling Path Sum	Java		Medium	DP
218	1143	Longest Common Subsequence	Java		Medium	DP
219	583	Delete Operation for Two Strings	Java		Medium	DP
220	712	Minimum ASCII Delete Sum for Two Strings	Java		Medium	DP
221	72	Edit Distance	Java		Hard	DP
222	416	Partition Equal Subset Sum	Java		Medium	DP
223	435	Non-overlapping Intervals 2	Java		Medium	Greedy
224	452	Minimum Number of Arrows to Burst Balloons	Java		Medium	Greedy
225	134	Gas Station	Java		Medium	Greedy
226	45	Jump Game II	Java		Medium	Greedy
227	64	Minimum Path Sum	Java		Medium	DP
228	174	Dungeon Game	Java		Hard	DP
229	514	Freedom Trail	Java		Hard	DP
230	10	Regular Expression Matching	Java		Hard	DP
231	366	Find Leaves of Binary Tree	Java		Medium	Tree
232	875	Koko Eating Bananas	Java		Medium	Binary Search
233	1011	Capacity To Ship Packages Within D Days	Java		Medium	Binary Search
234	74	Search a 2D Matrix	Java		Medium	Binary Search
235	81	Search in Rotated Sorted Array II	Java		Medium	Binary Search
236	153	Find Minimum in Rotated Sorted Array	Java		Medium	Binary Search
237	154	Find Minimum in Rotated Sorted Array II	Java		Hard	Binary Search
238	243	Shortest Word Distance	Java		Easy	Two Pointers
239	244	Shortest Word Distance II	Java		Medium	Two Pointers
240	142	Linked List Cycle II	Java		Medium	Two Pointers
241	167	Two Sum II - Input array is sorted	Java		Easy	Two Pointers
242	245	Shortest Word Distance III	Java		Medium	Array
243	567	Permutation in String	Java		Medium	Sliding Window
244	438	Find All Anagrams in a String	Java		Medium	Sliding Window
245	159	Longest Substring with At Most Two Distinct Characters	Java		Medium	Sliding Window
246	487	Max Consecutive Ones II	Java		Medium	Sliding Window
247	30	Substring with Concatenation of All Words	Java		Hard	Sliding Window
248	205	Isomorphic Strings	Java		Easy	String
249	44	Wildcard Matching	Java		Hard	Dynamic Programming
250	122	Best Time to Buy and Sell Stock II	Java		Easy	Dynamic Programming
251	123	Best Time to Buy and Sell Stock III	Java		Hard	Dynamic Programming
252	188	Best Time to Buy and Sell Stock IV	Java		Hard	Dynamic Programming
253	309	Best Time to Buy and Sell Stock with Cooldown	Java		Medium	Dynamic Programming
254	714	Best Time to Buy and Sell Stock with Transaction Fee	Java		Medium	Dynamic Programming
255	111	Minimum Depth of Binary Tree	Java		Easy	BFS
256	752	Open the Lock	Java		Medium	BFS
257	126	Word Ladder II	Java		Hard	BFS
258	130	Surrounded Regions	Java		Medium	DFS
259	179	Largest Number	Java		Medium	Sorting
260	1288	Remove Covered Intervals 2	Java		Medium	Sorting
261	986	Interval List Intersections	Java		Medium	Two Pointers
262	698	Partition to K Equal Sum Subsets	Java		Medium	Back Tracking
263	57	Insert Interval	Java		Medium	Array
264	77	Combinations	Java		Medium	Back Tracking
265	773	Sliding Puzzle 2	Java		Hard	BFS
266	231	Power of Two	Java		Easy	Bit Manipulation
267	793	Preimage Size of Factorial Zeroes Function	Java		Hard	Binary Search Math
268	372	Super Pow	Java		Medium	Math
269	659	Split Array into Consecutive Subsequences	Java		Medium	Hash Table
270	990	Satisfiability of Equality Equations	Java		Medium	Union Find
271	128	Longest Consecutive Sequence	Java		Medium	Union Find
272	460	LFU Cache	Java		Hard	Design
273	355	Design Twitter	Java		Medium	Design
274	496	Next Greater Element I	Java		Easy	Monotonic Stack
275	503	Next Greater Element II	Java		Medium	Monotonic Stack
276	739	Daily Temperatures 2	Java		Medium	Monotonic Stack
277	870	Advantage Shuffle	Java		Medium	Greedy
278	211	Design Add and Search Words Data Structure	Java		Medium	Trie
279	91	Decode Ways	Java		Medium	Dynamic Programming
280	287	Find the Duplicate Number 2	Java		Medium	Two Pointers
281	329	Longest Increasing Path in a Matrix 2	Java		Hard	DFS
282	1262	Greatest Sum Divisible by Three	Java		Medium	DP
283	560	Subarray Sum Equals K	Java		Medium	Prefix sum
284	1509	Minimum Difference Between Largest and Smallest Value in Three Moves	Java		Medium	Array
285	1877	Minimize Maximum Pair Sum in Array	Java		Medium	Greedy
286	1049	Last Stone Weight II	Java		Medium	Dynamic Programming
287	68	Text Justification	Java		Hard	Simulation
288	359	Logger Rate Limiter	Java		Easy	Hash Map
289	833	Find And Replace in String	Java		Medium	Hash Map String
290	710	Random Pick with Blacklist	Java		Hard	Hash Map Random
291	317	Shortest Distance from All Buildings	Java		Hard	BFS
292	1277	Count Square Submatrices with All Ones 2	Java		Medium	Dynamic Programming
293	498	Diagonal Traverse	Java		Medium	Simulation
294	1424	Diagonal Traverse II	Java		Medium	Sorting
295	360	Sort Transformed Array	Java		Medium	Sorting
296	743	Network Delay Time	Java		Medium	BFS``Dijkstra
297	1514	Path with Maximum Probability 2	Java		Medium	BFS``Dijkstra
298	2013	Detect Squares	Java		Medium	Design Counting
299	97	Interleaving String	Java		Medium	Dynamic Programming
300	189	Rotate Array	Java		Medium	Math
301	905	Sort Array By Parity	Java		Easy	Sorting
302	921	Minimum Add to Make Parentheses Valid	Java		Medium	Stack
303	780	Reaching Points	Java		Hard	Math Tree
304	515	Find Largest Value in Each Tree Row	Java		Medium	Tree
305	647	Palindromic Substrings	Java		Medium	Dynamic Programming
306	1347	Minimum Number of Steps to Make Two Strings Anagram	Java		Medium	Hash Table
307	256	Paint House	Java		Medium	Dynamic Programming
308	40	Combination Sum II	Java		Medium	Back tracking
309	453	Minimum Moves to Equal Array Elements	Java		Medium	Array
310	696	Count Binary Substrings	Java		Easy	String
311	1048	Longest String Chain	Java		Medium	Dynamic Programming
312	1654	Minimum Jumps to Reach Home	Java		Medium	BFS
313	1604	Alert Using Same Key-Card Three or More Times in a One Hour Period	Java		Medium	Hash Table
314	209	Minimum Size Subarray Sum	Java		Medium	Sliding Window
315	969	Pancake Sorting	Java		Medium	Sorting
316	658	Find K Closest Elements	Java		Medium	Binary Search
317	843	Guess the Word	Java		Hard	Greedy
318	1648	Sell Diminishing-Valued Colored Balls	Java		Medium	Greedy
319	552	Student Attendance Record II	Java		Hard	Dynamic Programming
320	1094	Car Pooling	Java		Medium	Heap
321	417	Pacific Atlantic Water Flow	Java		Medium	DFS
322	305	Number of Islands II	Java		Medium	Union Find
323	767	Reorganize String	Java		Medium	Greedy
324	1293	Shortest Path in a Grid with Obstacles Elimination	Java		Hard	DFS
325	304	Range Sum Query 2D - Immutable	Java		Medium	Dynamic Programming
326	792	Number of Matching Subsequences	Java		Medium	String
327	489	Robot Room Cleaner	Java		Hard	DFS
328	504	Base 7	Java		Easy	Math
329	2007	Find Original Array From Doubled Array	Java		Medium	Hash Table
330	1209	Remove All Adjacent Duplicates in String II	Java		Medium	Stack
331	1047	Remove All Adjacent Duplicates in String	Java		Easy	Stack
332	430	Flatten a Multilevel Doubly Linked List	Java		Medium	DFS
333	1472	Design Browser History	Java		Medium	Stack
334	343	Integer Break	Java		Medium	Dynamic Programming
335	1029	Two City Scheduling	Java		Medium	Sorting Greedy
336	1396	Design Underground System	Java		Medium	Design
337	24	Swap Nodes in Pairs	Java		Medium	Linked List
338	1091	Shortest Path in Binary Matrix	Java		Medium	BFS A*
339	399	Evaluate Division	Java		Medium	DFS
340	394	Decode String	Java		Medium	Stack
341	542	01 Matrix	Java		Medium	BFS
342	1169	Invalid Transactions	Java		Medium	Sorting
343	723	Candy Crush	Java		Medium	Simulation
344	1244	Design A Leaderboard	Java		Medium	Design
345	1274	Number of Ships in a Rectangle	Java		Hard	Devide and Conquer
346	987	Vertical Order Traversal of a Binary Tree	Java		Hard	Tree
347	445	Add Two Numbers II	Java		Medium	Stack
348	1583	Count Unhappy Friends	Java		Medium	Simulation
349	314	Binary Tree Vertical Order Traversal	Java		Medium	Tree
350	611	Valid Triangle Number	Java		Medium	Greedy Two Pointer
351	315	Count of Smaller Numbers After Self	Java		Hard	Merge Sort
352	390	Elimination Game	Java		Medium	Math Recursion
353	1614	Maximum Nesting Depth of the Parentheses	Java		Easy	Stack
354	582	Kill Process	Java		Medium	Tree
355	1188	Design Bounded Blocking Queue	Java		Medium	Concurrency
356	694	Number of Distinct Islands	Java		Medium	DFS
357	31	Next Permutation	Java		Medium	Two Pointers