README.md

ID	Title	Difficulty	Note	Java	Python	Ruby	JavaScript	C++
001	Two Sum	Easy	noNote	Java	Python	Ruby	JavaScript	no
002	Add Two Numbers	Medium	noNote	Java	Python	Ruby	JavaScript	no
003	Longest Substring Without Repeating Characters	Medium	noNote	Java	Python	no	no	no
004	Median of Two Sorted Arrays	Hard	noNote	no	no	no	no	no
005	Longest Palindromic Substring	Medium	noNote	no	no	no	no	no
006	ZigZag Conversion	Medium	noNote	Java	Python	no	no	no
007	Reverse Integer	Easy	noNote	Java	Python	Ruby	no	no
008	String to Integer (atoi)	Medium	noNote	Java	no	no	no	no
009	Palindrome Number	Easy	noNote	Java	Python	Ruby	no	no
010	Regular Expression Matching	Hard	noNote	Java	no	no	no	no
011	Container With Most Water	Medium	noNote	Java	no	no	no	no
012	Integer to Roman	Medium	noNote	Java	Python	no	no	no
013	Roman to Integer	Easy	noNote	Java	Python	no	no	no
014	Longest Common Prefix	Easy	noNote	Java	Python	no	no	no
015	3Sum	Medium	noNote	Java	Python	Ruby	JavaScript	no
016	3Sum Closest	Medium	noNote	Java	no	no	no	no
017	Letter Combinations of a Phone Number	Medium	noNote	Java	Python	no	no	no
018	4Sum	Medium	noNote	Java	no	no	no	no
019	Remove Nth Node From End of List	Medium	noNote	Java	Python	Ruby	no	no
020	Valid Parentheses	Easy	noNote	Java	no	no	no	no
021	Merge Two Sorted Lists	Easy	noNote	Java	Python	Ruby	no	no
022	Generate Parentheses	Medium	noNote	Java	Python	no	no	no
023	Merge k Sorted Lists	Hard	noNote	Java	Python	Ruby	no	no
024	Swap Nodes in Pairs	Medium	noNote	Java	Python	no	no	no
025	Reverse Nodes in k-Group	Hard	noNote	Java	no	no	no	no
026	Remove Duplicates from Sorted Array	Easy	noNote	Java	Python	no	no	no
027	Remove Element	Easy	noNote	Java	Python	no	no	no
028	Implement strStr()	Easy	noNote	Java	no	no	no	no
029	Divide Two Integers	Medium	noNote	Java	no	no	no	no
030	Substring with Concatenation of All Words	Hard	noNote	no	no	no	no	no
031	Next Permutation	Medium	noNote	Java	Python	no	no	no
032	Longest Valid Parentheses	Hard	noNote	Java	no	no	no	no
033	Search in Rotated Sorted Array	Medium	noNote	Java	no	no	no	no
034	Search for a Range	Medium	noNote	Java	Python	no	no	no
035	Search Insert Position	Easy	noNote	Java	Python	no	no	no
036	Valid Sudoku	Medium	noNote	Java	no	no	no	no
037	Sudoku Solver	Hard	noNote	Java	no	no	no	no
038	Count and Say	Easy	noNote	Java	no	no	no	no
039	Combination Sum	Medium	noNote	Java	Python	no	no	no
040	Combination Sum II	Medium	noNote	Java	no	no	no	no
041	First Missing Positive	Hard	noNote	Java	Python	no	no	no
042	Trapping Rain Water	Hard	noNote	Java	no	no	no	no
043	Multiply Strings	Medium	noNote	Java	Python	no	no	no
044	Wildcard Matching	Hard	noNote	no	no	no	no	no
045	Jump Game II	Hard	noNote	Java	no	no	no	no
046	Permutations	Medium	noNote	Java	Python	no	no	no
047	Permutations II	Medium	noNote	Java	Python	no	no	no
048	Rotate Image	Medium	noNote	Java	Python	no	no	no
049	Group Anagrams	Medium	noNote	Java	Python	no	no	no
050	Pow(x, n)	Medium	noNote	Java	Python	no	no	no
051	N-Queens	Hard	noNote	Java	Python	no	no	no
052	N-Queens II	Hard	noNote	Java	Python	no	no	no
053	Maximum Subarray	Easy	noNote	Java	Python	no	no	no
054	Spiral Matrix	Medium	noNote	Java	Python	no	no	no
055	Jump Game	Medium	noNote	Java	Python	no	JavaScript	no
056	Merge Intervals	Medium	noNote	Java	no	no	no	no
057	Insert Interval	Hard	noNote	Java	Python	no	no	no
058	Length of Last Word	Easy	noNote	Java	Python	no	no	no
059	Spiral Matrix II	Medium	noNote	Java	Python	no	no	no
060	Permutation Sequence	Medium	noNote	Java	Python	no	no	no
061	Rotate List	Medium	noNote	Java	Python	no	no	no
062	Unique Paths	Medium	noNote	Java	Python	no	no	no
063	Unique Paths II	Medium	noNote	Java	Python	no	no	no
064	Minimum Path Sum	Medium	noNote	Java	Python	no	no	no
065	Valid Number	Hard	noNote	no	no	no	no	no
066	Plus One	Easy	noNote	Java	no	no	no	no
067	Add Binary	Easy	noNote	Java	Python	no	no	no
068	Text Justification	Hard	noNote	Java	Python	no	no	no
069	Sqrt(x)	Easy	noNote	Java	Python	no	no	no
070	Climbing Stairs	Easy	noNote	Java	Python	no	no	no
071	Simplify Path	Medium	noNote	no	no	no	no	no
072	Edit Distance	Hard	noNote	Java	Python	no	no	no
073	Set Matrix Zeroes	Medium	noNote	Java	Python	no	no	no
074	Search a 2D Matrix	Medium	noNote	Java	Python	no	no	no
075	Sort Colors	Medium	noNote	Java	Python	no	no	no
076	Minimum Window Substring	Hard	noNote	no	no	no	no	no
077	Combinations	Medium	noNote	Java	Python	no	no	no
078	Subsets	Medium	noNote	Java	Python	no	no	no
079	Word Search	Medium	noNote	Java	no	no	no	no
080	Remove Duplicates from Sorted Array II	Medium	noNote	Java	Python	no	no	no
081	Search in Rotated Sorted Array II	Medium	noNote	Java	no	no	no	no
082	Remove Duplicates from Sorted List II	Medium	noNote	Java	Python	no	no	no
083	Remove Duplicates from Sorted List	Easy	noNote	Java	Python	no	no	no
084	Largest Rectangle in Histogram	Hard	noNote	no	no	no	no	no
085	Maximal Rectangle	Hard	noNote	no	no	no	no	no
086	Partition List	Medium	noNote	Java	Python	no	no	no
087	Scramble String	Hard	noNote	Java	Python	no	no	no
088	Merge Sorted Array	Easy	noNote	Java	Python	no	no	no
089	Gray Code	Medium	noNote	Java	Python	no	no	no
090	Subsets II	Medium	noNote	Java	Python	no	no	no
091	Decode Ways	Medium	noNote	Java	Python	no	no	no
092	Reverse Linked List II	Medium	noNote	Java	no	no	no	no
093	Restore IP Addresses	Medium	noNote	Java	Python	no	no	no
094	Binary Tree Inorder Traversal	Medium	noNote	Java	Python	Ruby	no	no
095	Unique Binary Search Trees II	Medium	noNote	Java	no	no	no	no
096	Unique Binary Search Trees	Medium	noNote	Java	Python	no	no	no
097	Interleaving String	Hard	noNote	Java	Python	no	no	no
098	Validate Binary Search Tree	Medium	noNote	Java	Python	Ruby	no	no
099	Recover Binary Search Tree	Hard	noNote	no	Python	no	no	no
100	Same Tree	Easy	noNote	Java	Python	Ruby	no	no
101	Symmetric Tree	Easy	noNote	Java	Python	Ruby	no	no
102	Binary Tree Level Order Traversal	Medium	noNote	Java	Python	no	no	no
103	Binary Tree Zigzag Level Order Traversal	Medium	noNote	Java	Python	no	no	no
104	Maximum Depth of Binary Tree	Easy	noNote	Java	Python	Ruby	no	no
105	Construct Binary Tree from Preorder and Inorder Traversal	Medium	noNote	Java	Python	Ruby	no	no
106	Construct Binary Tree from Inorder and Postorder Traversal	Medium	noNote	Java	Python	Ruby	no	no
107	Binary Tree Level Order Traversal II	Easy	noNote	Java	Python	no	no	no
108	Convert Sorted Array to Binary Search Tree	Easy	noNote	Java	Python	no	no	no
109	Convert Sorted List to Binary Search Tree	Medium	noNote	Java	Python	no	no	no
110	Balanced Binary Tree	Easy	noNote	Java	Python	Ruby	no	no
111	Minimum Depth of Binary Tree	Easy	noNote	Java	Python	Ruby	no	no
112	Path Sum	Easy	noNote	Java	Python	Ruby	no	no
113	Path Sum II	Medium	noNote	Java	Python	no	no	no
114	Flatten Binary Tree to Linked List	Medium	noNote	Java	Python	no	no	no
115	Distinct Subsequences	Hard	noNote	no	no	no	no	no
116	Populating Next Right Pointers in Each Node	Medium	noNote	Java	Python	no	no	no
117	Populating Next Right Pointers in Each Node II	Medium	noNote	Java	Python	no	no	no
118	Pascal's Triangle	Easy	noNote	Java	Python	no	no	no
119	Pascal's Triangle II	Easy	noNote	Java	Python	no	no	no
120	Triangle	Medium	noNote	Java	Python	no	no	no
121	Best Time to Buy and Sell Stock	Easy	noNote	Java	no	no	no	no
122	Best Time to Buy and Sell Stock II	Easy	noNote	Java	no	no	no	no
123	Best Time to Buy and Sell Stock III	Hard	noNote	Java	no	no	no	no
124	Binary Tree Maximum Path Sum	Hard	noNote	Java	no	no	no	no
125	Valid Palindrome	Easy	noNote	Java	no	no	no	no
126	Word Ladder II	Hard	noNote	no	no	no	no	no
127	Word Ladder	Medium	noNote	Java	no	no	no	no
128	Longest Consecutive Sequence	Hard	noNote	Java	no	no	no	no
129	Sum Root to Leaf Numbers	Medium	noNote	Java	Python	no	no	no
130	Surrounded Regions	Medium	noNote	Java	no	no	no	no
131	Palindrome Partitioning	Medium	noNote	Java	no	no	no	no
132	Palindrome Partitioning II	Hard	noNote	no	no	no	no	no
133	Clone Graph	Medium	noNote	Java	Python	no	no	no
134	Gas Station	Medium	noNote	Java	Python	no	no	no
135	Candy	Hard	noNote	Java	no	no	no	no
136	Single Number	Easy	noNote	Java	Python	no	no	no
137	Single Number II	Medium	noNote	Java	no	no	no	no
138	Copy List with Random Pointer	Medium	noNote	Java	Python	no	no	no
139	Word Break	Medium	noNote	Java	no	no	no	no
140	Word Break II	Hard	noNote	Java	no	no	no	no
141	Linked List Cycle	Easy	noNote	Java	Python	no	no	no
142	Linked List Cycle II	Medium	noNote	Java	Python	no	no	no
143	Reorder List	Medium	noNote	Java	Python	no	no	no
144	Binary Tree Preorder Traversal	Medium	noNote	Java	Python	Ruby	no	no
145	Binary Tree Postorder Traversal	Hard	noNote	Java	Python	no	no	no
146	LRU Cache	Hard	noNote	Java	Python	no	no	no
147	Insertion Sort List	Medium	noNote	Java	no	no	no	no
148	Sort List	Medium	noNote	Java	Python	no	no	no
149	Max Points on a Line	Hard	noNote	Java	no	no	no	no
150	Evaluate Reverse Polish Notation	Medium	noNote	Java	no	no	no	no
151	Reverse Words in a String	Medium	noNote	Java	no	no	no	no
152	Maximum Product Subarray	Medium	noNote	Java	no	no	no	no
153	Find Minimum in Rotated Sorted Array	Medium	noNote	Java	no	no	no	no
154	Find Minimum in Rotated Sorted Array II	Hard	noNote	Java	no	no	no	no
155	Min Stack	Easy	noNote	Java	no	no	no	no
156	Binary Tree Upside Down	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
157	Read N Characters Given Read4	Easy	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
158	Read N Characters Given Read4 II - Call multiple times	Hard	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
159	Longest Substring with At Most Two Distinct Characters	Hard	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
160	Intersection of Two Linked Lists	Easy	noNote	Java	Python	no	no	no
161	One Edit Distance	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
162	Find Peak Element	Medium	noNote	Java	no	no	no	no
163	Missing Ranges	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
164	Maximum Gap	Hard	noNote	Java	no	no	no	no
165	Compare Version Numbers	Medium	noNote	Java	Python	no	no	no
166	Fraction to Recurring Decimal	Medium	noNote	Java	no	no	no	no
167	Two Sum II - Input array is sorted	Easy	noNote	Java	no	no	no	no
168	Excel Sheet Column Title	Easy	noNote	Java	Python	no	no	no
169	Majority Element	Easy	noNote	Java	Python	no	no	no
170	Two Sum III - Data structure design	Easy	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
171	Excel Sheet Column Number	Easy	noNote	Java	Python	no	no	no
172	Factorial Trailing Zeroes	Easy	noNote	Java	Python	no	no	no
173	Binary Search Tree Iterator	Medium	noNote	Java	no	no	no	no
174	Dungeon Game	Hard	noNote	no	no	no	no	no
179	Largest Number	Medium	noNote	Java	Python	no	no	no
186	Reverse Words in a String II	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
187	Repeated DNA Sequences	Medium	noNote	Java	no	no	no	no
188	Best Time to Buy and Sell Stock IV	Hard	noNote	no	no	no	no	no
189	Rotate Array	Easy	noNote	Java	Python	no	no	no
190	Reverse Bits	Easy	noNote	Java	Python	no	no	no
191	Number of 1 Bits	Easy	noNote	Java	Python	no	no	no
198	House Robber	Easy	noNote	Java	Python	no	no	no
199	Binary Tree Right Side View	Medium	noNote	Java	Python	no	no	no
200	Number of Islands	Medium	noNote	Java	Python	no	no	no
201	Bitwise AND of Numbers Range	Medium	noNote	Java	no	no	no	no
202	Happy Number	Easy	noNote	Java	Python	no	no	no
203	Remove Linked List Elements	Easy	noNote	Java	Python	no	no	no
204	Count Primes	Easy	noNote	Java	no	no	no	no
205	Isomorphic Strings	Easy	noNote	Java	Python	no	no	no
206	Reverse Linked List	Easy	noNote	Java	Python	no	no	no
207	Course Schedule	Medium	noNote	no	no	no	no	no
208	Implement Trie (Prefix Tree)	Medium	noNote	Java	no	no	no	no
209	Minimum Size Subarray Sum	Medium	noNote	no	no	no	no	no
210	Course Schedule II	Medium	noNote	no	no	no	no	no
211	Add and Search Word - Data structure design	Medium	noNote	no	no	no	no	no
212	Word Search II	Hard	noNote	Java	no	no	no	no
213	House Robber II	Medium	noNote	Java	Python	no	no	no
214	Shortest Palindrome	Hard	noNote	no	no	no	no	no
215	Kth Largest Element in an Array	Medium	noNote	Java	Python	no	no	no
216	Combination Sum III	Medium	noNote	Java	Python	no	no	no
217	Contains Duplicate	Easy	noNote	Java	Python	no	no	no
218	The Skyline Problem	Hard	noNote	no	no	no	no	no
219	Contains Duplicate II	Easy	noNote	Java	Python	no	no	no
220	Contains Duplicate III	Medium	noNote	no	no	no	no	no
221	Maximal Square	Medium	noNote	Java	no	no	no	no
222	Count Complete Tree Nodes	Medium	noNote	Java	Python	no	no	no
223	Rectangle Area	Medium	noNote	Java	Python	no	no	no
224	Basic Calculator	Hard	noNote	no	no	no	no	no
225	Implement Stack using Queues	Easy	noNote	Java	no	no	no	no
226	Invert Binary Tree	Easy	noNote	Java	Python	Ruby	no	no
227	Basic Calculator II	Medium	noNote	no	no	no	no	no
228	Summary Ranges	Medium	noNote	Java	Python	no	no	no
229	Majority Element II	Medium	noNote	Java	no	no	no	no
230	Kth Smallest Element in a BST	Medium	noNote	Java	Python	Ruby	no	no
231	Power of Two	Easy	noNote	Java	Python	no	no	no
232	Implement Queue using Stacks	Easy	noNote	Java	no	no	no	no
233	Number of Digit One	Hard	noNote	no	no	no	no	no
234	Palindrome Linked List	Easy	noNote	Java	no	no	no	no
235	Lowest Common Ancestor of a Binary Search Tree	Easy	noNote	Java	Python	no	no	no
236	Lowest Common Ancestor of a Binary Tree	Medium	noNote	Java	Python	no	no	no
237	Delete Node in a Linked List	Easy	noNote	Java	Python	no	no	no
238	Product of Array Except Self	Medium	noNote	Java	Python	no	no	no
239	Sliding Window Maximum	Hard	noNote	Java	Python	no	no	no
240	Search a 2D Matrix II	Medium	noNote	Java	no	no	no	no
241	Different Ways to Add Parentheses	Medium	noNote	no	no	no	no	no
242	Valid Anagram	Easy	noNote	Java	Python	no	no	no
243	Shortest Word Distance	Easy	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
244	Shortest Word Distance II	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
245	Shortest Word Distance III	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
246	Strobogrammatic Number	Easy	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
247	Strobogrammatic Number II	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
248	Strobogrammatic Number III	Hard	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
249	Group Shifted Strings	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
250	Count Univalue Subtrees	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
251	Flatten 2D Vector	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
252	Meeting Rooms	Easy	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
253	Meeting Rooms II	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
254	Factor Combinations	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
255	Verify Preorder Sequence in Binary Search Tree	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
256	Paint House	Easy	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
257	Binary Tree Paths	Easy	noNote	Java	Python	no	no	no
258	Add Digits	Easy	noNote	Java	Python	no	no	no
259	3Sum Smaller	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
260	Single Number III	Medium	noNote	Java	Python	no	no	no
261	Graph Valid Tree	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
263	Ugly Number	Easy	noNote	Java	Python	no	no	no
264	Ugly Number II	Medium	noNote	Java	no	no	no	no
265	Paint House II	Hard	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
266	Palindrome Permutation	Easy	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
267	Palindrome Permutation II	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
268	Missing Number	Easy	noNote	Java	Python	no	no	no
269	Alien Dictionary	Hard	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
270	Closest Binary Search Tree Value	Easy	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
271	Encode and Decode Strings	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
272	Closest Binary Search Tree Value II	Hard	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
273	Integer to English Words	Hard	noNote	Java	Python	no	no	no
274	H-Index	Medium	noNote	Java	no	no	no	no
275	H-Index II	Medium	noNote	Java	no	no	no	no
276	Paint Fence	Easy	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
277	Find the Celebrity	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
278	First Bad Version	Easy	noNote	Java	Python	no	no	no
279	Perfect Squares	Medium	noNote	Java	no	no	no	no
280	Wiggle Sort	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
281	Zigzag Iterator	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
282	Expression Add Operators	Hard	noNote	no	no	no	no	no
283	Move Zeroes	Easy	noNote	Java	Python	no	no	no
284	Peeking Iterator	Medium	noNote	Java	no	no	no	no
285	Inorder Successor in BST	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
286	Walls and Gates	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
287	Find the Duplicate Number	Medium	noNote	Java	Python	no	no	no
288	Unique Word Abbreviation	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
289	Game of Life	Medium	noNote	Java	Python	no	no	no
290	Word Pattern	Easy	noNote	Java	Python	no	no	no
291	Word Pattern II	Hard	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
292	Nim Game	Easy	noNote	Java	Python	no	no	no
293	Flip Game	Easy	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
294	Flip Game II	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
295	Find Median from Data Stream	Hard	noNote	Java	no	no	no	no
296	Best Meeting Point	Hard	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
297	Serialize and Deserialize Binary Tree	Hard	noNote	Java	no	no	no	no
298	Binary Tree Longest Consecutive Sequence	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
299	Bulls and Cows	Medium	noNote	Java	Python	no	no	no
300	Longest Increasing Subsequence	Medium	noNote	Java	no	no	no	no
301	Remove Invalid Parentheses	Hard	noNote	no	no	no	no	no
302	Smallest Rectangle Enclosing Black Pixels	Hard	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
303	Range Sum Query - Immutable	Easy	noNote	Java	Python	no	no	no
304	Range Sum Query 2D - Immutable	Medium	noNote	no	Python	no	no	no
305	Number of Islands II	Hard	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
306	Additive Number	Medium	noNote	Java	Python	no	no	no
307	Range Sum Query - Mutable	Medium	noNote	Java	no	no	no	no
308	Range Sum Query 2D - Mutable	Hard	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
309	Best Time to Buy and Sell Stock with Cooldown	Medium	noNote	Java	no	no	no	no
310	Minimum Height Trees	Medium	noNote	no	no	no	no	no
311	Sparse Matrix Multiplication	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
312	Burst Balloons	Hard	noNote	no	no	no	no	no
313	Super Ugly Number	Medium	noNote	no	no	no	no	no
314	Binary Tree Vertical Order Traversal	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
315	Count of Smaller Numbers After Self	Hard	noNote	Java	Python	no	no	no
316	Remove Duplicate Letters	Hard	noNote	Java	no	no	no	no
317	Shortest Distance from All Buildings	Hard	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
318	Maximum Product of Word Lengths	Medium	noNote	Java	Python	no	no	no
319	Bulb Switcher	Medium	noNote	Java	Python	no	no	no
320	Generalized Abbreviation	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
321	Create Maximum Number	Hard	noNote	no	no	no	no	no
322	Coin Change	Medium	noNote	Java	no	no	no	no
323	Number of Connected Components in an Undirected Graph	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
324	Wiggle Sort II	Medium	noNote	no	Python	no	no	no
325	Maximum Size Subarray Sum Equals k	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
326	Power of Three	Easy	noNote	Java	Python	no	no	no
327	Count of Range Sum	Hard	noNote	no	no	no	no	no
328	Odd Even Linked List	Medium	noNote	Java	Python	no	no	no
329	Longest Increasing Path in a Matrix	Hard	noNote	Java	Python	no	no	no
330	Patching Array	Hard	noNote	no	no	no	no	no
331	Verify Preorder Serialization of a Binary Tree	Medium	noNote	Java	Python	no	no	no
332	Reconstruct Itinerary	Medium	noNote	no	no	no	no	no
333	Largest BST Subtree	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
334	Increasing Triplet Subsequence	Medium	noNote	Java	Python	no	no	no
335	Self Crossing	Hard	noNote	no	no	no	no	no
336	Palindrome Pairs	Hard	noNote	no	no	no	no	no
337	House Robber III	Medium	noNote	Java	Python	no	no	no
338	Counting Bits	Medium	noNote	Java	Python	no	no	no
339	Nested List Weight Sum	Easy	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
340	Longest Substring with At Most K Distinct Characters	Hard	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
341	Flatten Nested List Iterator	Medium	noNote	Java	Python	no	no	no
342	Power of Four	Easy	noNote	Java	Python	no	no	no
343	Integer Break	Medium	noNote	Java	Python	no	no	no
344	Reverse String	Easy	noNote	Java	Python	no	no	no
345	Reverse Vowels of a String	Easy	noNote	Java	Python	no	no	no
346	Moving Average from Data Stream	Easy	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
347	Top K Frequent Elements	Medium	noNote	Java	Python	no	no	no
348	Design Tic-Tac-Toe	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
349	Intersection of Two Arrays	Easy	noNote	Java	no	no	no	no
350	Intersection of Two Arrays II	Easy	noNote	Java	no	no	no	no
351	Android Unlock Patterns	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
352	Data Stream as Disjoint Intervals	Hard	noNote	Java	no	no	no	no
353	Design Snake Game	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
354	Russian Doll Envelopes	Hard	noNote	Java	no	no	no	no
355	Design Twitter	Medium	noNote	Java	no	no	no	no
356	Line Reflection	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
357	Count Numbers with Unique Digits	Medium	noNote	Java	no	no	no	no
358	Rearrange String k Distance Apart	Hard	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
359	Logger Rate Limiter	Easy	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
360	Sort Transformed Array	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
361	Bomb Enemy	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
362	Design Hit Counter	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
363	Max Sum of Rectangle No Larger Than K	Hard	noNote	Java	no	no	no	no
364	Nested List Weight Sum II	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
365	Water and Jug Problem	Medium	noNote	Java	no	no	no	no
366	Find Leaves of Binary Tree	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
367	Valid Perfect Square	Easy	noNote	Java	no	no	no	no
368	Largest Divisible Subset	Medium	noNote	Java	no	no	no	no
369	Plus One Linked List	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
370	Range Addition	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
371	Sum of Two Integers	Easy	noNote	Java	no	no	no	no
372	Super Pow	Medium	noNote	Java	no	no	no	no
373	Find K Pairs with Smallest Sums	Medium	noNote	Java	no	no	no	no
374	Guess Number Higher or Lower	Easy	noNote	Java	no	no	no	no
375	Guess Number Higher or Lower II	Medium	noNote	Java	no	no	no	no
376	Wiggle Subsequence	Medium	noNote	Java	no	no	no	no
377	Combination Sum IV	Medium	noNote	Java	no	no	no	no
378	Kth Smallest Element in a Sorted Matrix	Medium	noNote	Java	no	no	no	no
379	Design Phone Directory	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
380	Insert Delete GetRandom O(1)	Medium	noNote	Java	no	no	no	no
381	Insert Delete GetRandom O(1) - Duplicates allowed	Hard	noNote	Java	no	no	no	no
382	Linked List Random Node	Medium	noNote	Java	no	no	no	no
383	Ransom Note	Easy	noNote	Java	no	no	no	no
384	Shuffle an Array	Medium	noNote	Java	no	no	no	no
385	Mini Parser	Medium	noNote	Java	no	no	no	no
386	Lexicographical Numbers	Medium	noNote	Java	no	no	no	no
387	First Unique Character in a String	Easy	noNote	Java	no	no	no	no
388	Longest Absolute File Path	Medium	noNote	Java	no	no	no	no
389	Find the Difference	Easy	noNote	Java	no	no	no	no
390	Elimination Game	Medium	noNote	Java	no	no	no	no
391	Perfect Rectangle	Hard	noNote	Java	no	no	no	no
392	Is Subsequence	Medium	noNote	Java	no	no	no	no
393	UTF-8 Validation	Medium	noNote	Java	no	no	no	no
394	Decode String	Medium	noNote	Java	no	no	no	no
395	Longest Substring with At Least K Repeating Characters	Medium	noNote	Java	no	no	no	no
396	Rotate Function	Medium	noNote	Java	no	no	no	no
397	Integer Replacement	Medium	noNote	Java	no	no	no	no
398	Random Pick Index	Medium	noNote	Java	no	no	no	no
399	Evaluate Division	Medium	noNote	no	no	no	no	no
400	Nth Digit	Easy	noNote	Java	no	no	no	no
401	Binary Watch	Easy	noNote	Java	no	no	no	no
402	Remove K Digits	Medium	noNote	Java	no	no	no	no
403	Frog Jump	Hard	noNote	Java	no	no	no	no
404	Sum of Left Leaves	Easy	noNote	Java	no	no	no	no
405	Convert a Number to Hexadecimal	Easy	noNote	Java	no	no	no	no
406	Queue Reconstruction by Height	Medium	noNote	Java	no	no	no	no
407	Trapping Rain Water II	Hard	noNote	no	no	no	no	no
408	Valid Word Abbreviation	Easy	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
409	Longest Palindrome	Easy	noNote	Java	no	no	no	no
410	Split Array Largest Sum	Hard	noNote	no	no	no	no	no
411	Minimum Unique Word Abbreviation	Hard	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
412	Fizz Buzz	Easy	noNote	no	no	no	no	no
413	Arithmetic Slices	Medium	noNote	no	no	no	no	no
414	Third Maximum Number	Easy	noNote	no	no	no	no	no
415	Add Strings	Easy	noNote	Java	no	no	no	no
416	Partition Equal Subset Sum	Medium	noNote	Java	no	no	no	no
417	Pacific Atlantic Water Flow	Medium	noNote	Java	no	no	no	no
418	Sentence Screen Fitting	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
419	Battleships in a Board	Medium	noNote	no	no	no	no	no
420	Strong Password Checker	Hard	noNote	no	no	no	no	no
421	Maximum XOR of Two Numbers in an Array	Medium	noNote	no	no	no	no	no
422	Valid Word Square	Easy	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
423	Reconstruct Original Digits from English	Medium	noNote	no	no	no	no	no
424	Longest Repeating Character Replacement	Medium	noNote	no	no	no	no	no
425	Word Squares	Hard	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
432	All O`one Data Structure	Hard	noNote	no	no	no	no	no
434	Number of Segments in a String	Easy	noNote	no	no	no	no	no
435	Non-overlapping Intervals	Medium	noNote	no	no	no	no	no
436	Find Right Interval	Medium	noNote	no	no	no	no	no
437	Path Sum III	Easy	noNote	no	no	no	no	no
438	Find All Anagrams in a String	Easy	noNote	no	no	no	no	no
439	Ternary Expression Parser	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
440	K-th Smallest in Lexicographical Order	Hard	noNote	no	no	no	no	no
441	Arranging Coins	Easy	noNote	no	no	no	no	no
442	Find All Duplicates in an Array	Medium	noNote	no	no	no	no	no
444	Sequence Reconstruction	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
445	Add Two Numbers II	Medium	noNote	no	no	no	no	no
446	Arithmetic Slices II - Subsequence	Hard	noNote	no	no	no	no	no
447	Number of Boomerangs	Easy	noNote	no	no	no	no	no
448	Find All Numbers Disappeared in an Array	Easy	noNote	no	no	no	no	no
449	Serialize and Deserialize BST	Medium	noNote	no	no	no	no	no
450	Delete Node in a BST	Medium	noNote	no	no	no	no	no
451	Sort Characters By Frequency	Medium	noNote	no	no	no	no	no
452	Minimum Number of Arrows to Burst Balloons	Medium	noNote	no	no	no	no	no
453	Minimum Moves to Equal Array Elements	Easy	noNote	no	no	no	no	no
454	4Sum II	Medium	noNote	no	no	no	no	no
455	Assign Cookies	Easy	noNote	no	no	no	no	no
456	132 Pattern	Medium	noNote	no	no	no	no	no
459	Repeated Substring Pattern	Easy	noNote	no	no	no	no	no
460	LFU Cache	Hard	noNote	no	no	no	no	no
461	Hamming Distance	Easy	noNote	no	no	no	no	no
462	Minimum Moves to Equal Array Elements II	Medium	noNote	no	no	no	no	no
463	Island Perimeter	Easy	noNote	no	no	no	no	no
464	Can I Win	Medium	noNote	no	no	no	no	no
465	Optimal Account Balancing	Hard	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
466	Count The Repetitions	Hard	noNote	no	no	no	no	no
467	Unique Substrings in Wraparound String	Medium	noNote	no	no	no	no	no
468	Validate IP Address	Medium	noNote	no	no	no	no	no
469	Convex Polygon	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
471	Encode String with Shortest Length	Hard	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
472	Concatenated Words	Hard	noNote	no	no	no	no	no
473	Matchsticks to Square	Medium	noNote	no	no	no	no	no
474	Ones and Zeroes	Medium	noNote	no	no	no	no	no
475	Heaters	Easy	noNote	no	no	no	no	no
476	Number Complement	Easy	noNote	no	no	no	no	no
477	Total Hamming Distance	Medium	noNote	no	no	no	no	no
480	Sliding Window Median	Hard	noNote	no	no	no	no	no
481	Magical String	Medium	noNote	no	no	no	no	no
482	License Key Formatting	Medium	noNote	no	no	no	no	no
483	Smallest Good Base	Hard	noNote	no	no	no	no	no
484	Find Permutation	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
485	Max Consecutive Ones	Easy	noNote	no	no	no	no	no
486	Predict the Winner	Medium	noNote	no	no	no	no	no
487	Max Consecutive Ones II	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
488	Zuma Game	Hard	noNote	no	no	no	no	no
490	The Maze	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
491	Increasing Subsequences	Medium	noNote	no	no	no	no	no
492	Construct the Rectangle	Easy	noNote	no	no	no	no	no
493	Reverse Pairs	Hard	noNote	no	no	no	no	no
494	Target Sum	Medium	noNote	no	no	no	no	no
495	Teemo Attacking	Medium	noNote	no	no	no	no	no
496	Next Greater Element I	Easy	noNote	no	no	no	no	no
498	Diagonal Traverse	Medium	noNote	no	no	no	no	no
499	The Maze III	Hard	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
500	Keyboard Row	Easy	noNote	no	no	no	no	no
501	Find Mode in Binary Search Tree	Easy	noNote	no	no	no	no	no
502	IPO	Hard	noNote	no	no	no	no	no
503	Next Greater Element II	Medium	noNote	no	no	no	no	no
504	Base 7	Easy	noNote	no	no	no	no	no
505	The Maze II	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
506	Relative Ranks	Easy	noNote	no	no	no	no	no
508	Most Frequent Subtree Sum	Medium	noNote	no	no	no	no	no
513	Find Bottom Left Tree Value	Medium	noNote	no	no	no	no	no
514	Freedom Trail	Hard	noNote	no	no	no	no	no
515	Find Largest Value in Each Tree Row	Medium	noNote	no	no	no	no	no
516	Longest Palindromic Subsequence	Medium	noNote	no	no	no	no	no
517	Super Washing Machines	Hard	noNote	no	no	no	no	no
520	Detect Capital	Easy	noNote	no	no	no	no	no
523	Continuous Subarray Sum	Medium	noNote	no	no	no	no	no
524	Longest Word in Dictionary through Deleting	Medium	noNote	no	no	no	no	no
525	Contiguous Array	Medium	noNote	no	no	no	no	no
526	Beautiful Arrangement	Medium	noNote	no	no	no	no	no
527	Word Abbreviation	Hard	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
529	Minesweeper	Medium	noNote	no	no	no	no	no
530	Minimum Absolute Difference in BST	Easy	noNote	no	no	no	no	no
531	Lonely Pixel I	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
532	K-diff Pairs in an Array	Easy	noNote	no	no	no	no	no
533	Lonely Pixel II	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
535	Encode and Decode TinyURL	Medium	noNote	no	no	no	no	no
536	Construct Binary Tree from String	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy
538	Convert BST to Greater Tree	Medium	noNote	no	no	no	no	no
539	Minimum Time Difference	Medium	noNote	no	no	no	no	no
541	Reverse String II	Easy	noNote	no	no	no	no	no
542	01 Matrix	Medium	noNote	no	no	no	no	no
543	Diameter of Binary Tree	Easy	noNote	no	no	no	no	no
544	Output Contest Matches	Medium	noBuy	noBuy	noBuy	noBuy	noBuy	noBuy