LeetCode

LeetCode Algorithms with C#, Java, Python and JavaScript

No.	Question	Difficulty	Solution	Status
1	Two Sum	Easy	C#, Java, Python, JS	✔️
2	Add Two Numbers	Medium	C#, Java, Python, JS	✔️
3	Longest Substring Without Repeating Characters	Medium	C#, Java, Python, JS	✔️
4	Median of Two Sorted Arrays	Hard	C#	✔️
5	Longest Palindromic Substring	Medium	C#, Java	✔️
6	ZigZag Conversion	Medium	C#, Java, Python, JS	✔️
7	Reverse Integer	Easy	C#, Java	✔️
8	String to Integer (atoi)	Medium	C#, JS	✔️
9	Palindrome Number	Easy	C#, Java, JS	✔️
10	Regular Expression Matching	Hard		➖
11	Container With Most Water	Medium	C#, Java, JS	✔️
12	Integer to Roman	Medium	C#, Java, JS	✔️
13	Roman to Integer	Easy	C#, Java, JS	✔️
14	Longest Common Prefix	Easy	C#, Java	✔️
15	3Sum	Medium	C#, Java, Python, JS	✔️
16	3Sum Closest	Medium	C#, Java, Python, JS	✔️
17	Letter Combinations of a Phone Number	Medium	C#, Java	✔️
18	4Sum	Medium	C#, Java, Python	✔️
19	Remove Nth Node From End of List	Medium	C#, Java, Python, JS	✔️
20	Valid Parentheses	Easy	C#, Java, Python, JS	✔️
21	Merge Two Sorted Lists	Easy	C#, Java, Python, JS	✔️
22	Generate Parentheses	Medium	C#, Java	✔️
23	Merge k Sorted Lists	Hard	C#, JS	✔️
24	Swap Nodes in Pairs	Medium	C#, Java, Python, JS	✔️
25	Reverse Nodes in k-Group	Hard	C#, Java	✔️
26	Remove Duplicates from Sorted Array	Easy	C#, JS	✔️
27	Remove Element	Easy	C#, Java, Python	✔️
28	Implement strStr()	Easy	C#, Java, JS	✔️
29	Divide Two Integers	Medium	C#, Java	✔️
30	Substring with Concatenation of All Words	Hard	C#	✔️
31	Next Permutation	Medium	C#, Java	✔️
32	Longest Valid Parentheses	Hard	C#, Java	✔️
33	Search in Rotated Sorted Array	Medium	C#, Java, JS	✔️
34	Find First and Last Position of Element in Sorted Array	Medium	C#, Java, JS	✔️
35	Search Insert Position	Easy	C#, Java, JS	✔️
36	Valid Sudoku	Medium	C#, Java, Python, JS	✔️
37	Sudoku Solver	Hard	C#, Java, JS	✔️
38	Count and Say	Medium	C#, JS	✔️
39	Combination Sum	Medium	C#, Java, JS	✔️
40	Combination Sum II	Medium	C#, Java, JS	✔️
41	First Missing Positive	Hard	C#	✔️
42	Trapping Rain Water	Hard	C#, Java, Python, JS	✔️
43	Multiply Strings	Medium	C#	✔️
44	Wildcard Matching	Hard		➖
45	Jump Game II	Medium	C#, Java, Python, JS	✔️
46	Permutations	Medium	C#, JS	✔️
47	Permutations II	Medium	C#, JS	✔️
48	Rotate Image	Medium	C#, JS	✔️
49	Group Anagrams	Medium	C#, Java, Python, JS	✔️
50	Pow(x, n)	Medium	C#, Java	✔️
51	N-Queens	Hard	C#, Java	✔️
52	N-Queens II	Hard	C#, Java	✔️
53	Maximum Subarray	Easy	C#, Java, Python, JS	✔️
54	Spiral Matrix	Medium	C#, Java, JS	✔️
55	Jump Game	Medium	C#, Java, JS	✔️
56	Merge Intervals	Medium	C#, Java, JS	✔️
57	Insert Interval	Medium	C#, Java, JS, Python	✔️
58	Length of Last Word	Easy	C#, JS	✔️
59	Spiral Matrix II	Medium	C#, Java, JS	✔️
60	Permutation Sequence	Hard	C#	✔️
61	Rotate List	Medium	C#, Java, Python, JS	✔️
62	Unique Paths	Medium	C#, JS	✔️
63	Unique Paths II	Medium	C#, Java	✔️
64	Minimum Path Sum	Medium	C#, JS	✔️
65	Valid Number	Hard	C#	✔️
66	Plus One	Easy	C#, Java	✔️
67	Add Binary	Easy	C#, Java, Python, JS	✔️
68	Text Justification	Hard	C#	✔️
69	Sqrt(x)	Easy	C#	✔️
70	Climbing Stairs	Easy	C#, Java, JS	✔️
71	Simplify Path	Medium	C#, Java, Python, JS	✔️
72	Edit Distance	Hard	C#, Java, JS	✔️
73	Set Matrix Zeroes	Medium	C#, Java	✔️
74	Search a 2D Matrix	Medium	C#, Java, Python, JS	✔️
75	Sort Colors	Medium	C#, Java	✔️
76	Minimum Window Substring	Hard	C#	✔️
77	Combinations	Medium	C#, Java	✔️
78	Subsets	Medium	C#, Java, Python, JS	✔️
79	Word Search	Medium	C#, Java, Python, JS	✔️
80	Remove Duplicates from Sorted Array II	Medium	C#, Java	✔️
81	Search in Rotated Sorted Array II	Medium	C#, Java	✔️
82	Remove Duplicates from Sorted List II	Medium	C#, Java, JS	✔️
83	Remove Duplicates from Sorted List	Easy	C#, Java, Python	✔️
84	Largest Rectangle in Histogram	Hard	C#, Java, JS	✔️
85	Maximal Rectangle	Hard	C#	✔️
86	Partition List	Medium	C#, Java, Python, JS	✔️
87	Scramble String	Hard	C#, JS	✔️
88	Merge Sorted Array	Easy	C#, Java, Python	✔️
89	Gray Code	Medium	C#, Java, JS	✔️
90	Subsets II	Medium	C#, Java, Python	✔️
91	Decode Ways	Medium	C#, Java, Python	✔️
92	Reverse Linked List II	Medium	C#, Java, Python, JS	✔️
93	Restore IP Addresses	Medium	C#, Java, JS	✔️
94	Binary Tree Inorder Traversal	Easy	C#, Java, JS	✔️
95	Unique Binary Search Trees II	Medium	C#	✔️
96	Unique Binary Search Trees	Medium	C#, JS	✔️
97	Interleaving String	Medium	C#, Java	✔️
98	Validate Binary Search Tree	Medium	C#, Java, Python	✔️
99	Recover Binary Search Tree	Medium	C#	✔️
100	Same Tree	Easy	C#, Java, Python, JS	✔️
101	Symmetric Tree	Easy	C#, Java, Python, JS	✔️
102	Binary Tree Level Order Traversal	Medium	C#, Java, Python	✔️
103	Binary Tree Zigzag Level Order Traversal	Medium	C#, Java, JS	✔️
104	Maximum Depth of Binary Tree	Easy	C#, Java, Python, JS	✔️
105	Construct Binary Tree from Preorder and Inorder Traversal	Medium	C#, Java	✔️
106	Construct Binary Tree from Inorder and Postorder Traversal	Medium	C#, JS	✔️
107	Binary Tree Level Order Traversal II	Medium	C#, Java	✔️
108	Convert Sorted Array to Binary Search Tree	Easy	C#, Java, Python, JS	✔️
109	Convert Sorted List to Binary Search Tree	Medium	C#, Java, JS	✔️
110	Balanced Binary Tree	Easy	C#, Java, Python	✔️
111	Minimum Depth of Binary Tree	Easy	C#, Java	✔️
112	Path Sum	Easy	C#, Java, Python, JS	✔️
113	Path Sum II	Medium	C#, Java, Python, JS	✔️
114	Flatten Binary Tree to Linked List	Medium	C#, Java	✔️
115	Distinct Subsequences	Hard	C#	✔️
116	Populating Next Right Pointers in Each Node	Medium	C#, JS	✔️
117	Populating Next Right Pointers in Each Node II	Medium	C#, JS	✔️
118	Pascal's Triangle	Easy	C#, Java, Python	✔️
119	Pascal's Triangle II	Easy	C#	✔️
120	Triangle	Medium	C#, Java, JS	✔️
121	Best Time to Buy and Sell Stock	Easy	C#, Java, Python, JS	✔️
122	Best Time to Buy and Sell Stock II	Easy	C#, Java, JS	✔️
123	Best Time to Buy and Sell Stock III	Hard	C#, Java	✔️
124	Binary Tree Maximum Path Sum	Hard	C#, JS	✔️
125	Valid Palindrome	Easy	C#, JS	✔️
126	Word Ladder II	Hard	C#	✔️
127	Word Ladder	Hard	C#	✔️
128	Longest Consecutive Sequence	Medium	C#, Java	✔️
129	Sum Root to Leaf Numbers	Medium	C#, Java, Python, JS	✔️
130	Surrounded Regions	Medium	C#, Java, JS	✔️
131	Palindrome Partitioning	Medium	C#, Java, JS, Python	✔️
132	Palindrome Partitioning II	Hard	C#	✔️
133	Clone Graph	Medium	C#, Java	✔️
134	Gas Station	Medium	C#, Java, Python, JS	✔️
135	Candy	Hard	C#, Java, Python, JS	✔️
136	Single Number	Easy	C#, JS	✔️
137	Single Number II	Medium	C#, Java	✔️
138	Copy List with Random Pointer	Medium	C#, Java, JS	✔️
139	Word Break	Medium	C#, Java	✔️
140	Word Break II	Hard	C#	✔️
141	Linked List Cycle	Easy	C#, Java, Python, JS	✔️
142	Linked List Cycle II	Medium	C#, Java, Python, JS	✔️
143	Reorder List	Medium	C#, Java, Python, JS	✔️
144	Binary Tree Preorder Traversal	Easy	C#, Java, JS	✔️
145	Binary Tree Postorder Traversal	Easy	C#, Java	✔️
146	LRU Cache	Medium	C#	✔️
147	Insertion Sort List	Medium	C#, Java, JS	✔️
148	Sort List	Medium	C#, Java, JS	✔️
149	Max Points on a Line	Hard	C#	✔️
150	Evaluate Reverse Polish Notation	Medium	C#, Java	✔️
151	Reverse Words in a String	Medium	C#, Java, Python	✔️
152	Maximum Product Subarray	Medium	C#, JS	✔️
153	Find Minimum in Rotated Sorted Array	Medium	C#, Java	✔️
154	Find Minimum in Rotated Sorted Array II	Hard	C#	✔️
155	Min Stack	Easy	C#, Java	✔️
156	Binary Tree Upside Down	Medium	C#	✔️
157	Read N Characters Given Read4	Easy	C#	✔️
158	Read N Characters Given Read4 II - Call multiple times	Hard		➖
159	Longest Substring with At Most Two Distinct Characters	Medium	C#, JS	✔️
160	Intersection of Two Linked Lists	Easy	C#, Java	✔️
161	One Edit Distance	Medium	C#, Java	✔️
162	Find Peak Element	Medium	C#, Java	✔️
163	Missing Ranges	Easy	C#	✔️
164	Maximum Gap	Hard	C#	✔️
165	Compare Version Numbers	Medium	C#, JS	✔️
166	Fraction to Recurring Decimal	Medium	C#	✔️
167	Two Sum II - Input array is sorted	Easy	C#, Java	✔️
168	Excel Sheet Column Title	Easy	C#, Java	✔️
169	Majority Element	Easy	C#, Java, JS	✔️
170	Two Sum III - Data structure design	Easy	C#	✔️
171	Excel Sheet Column Number	Easy	C#, JS	✔️
172	Factorial Trailing Zeroes	Easy	C#, Java	✔️
173	Binary Search Tree Iterator	Medium	C#, Java	✔️
174	Dungeon Game	Hard	C#, Java, Python	✔️
175	Combine Two Tables	Easy	MySQL, SQLServer	✔️
176	Second Highest Salary	Easy	MySQL, SQLServer	✔️
177	Nth Highest Salary	Medium	MySQL, SQLServer	✔️
178	Rank Scores	Medium	MySQL, SQLServer	✔️
179	Largest Number	Medium	C#, Java	✔️
180	Consecutive Numbers	Medium	MySQL, SQLServer	✔️
181	Employees Earning More Than Their Managers	Easy	MySQL, SQLServer	✔️
182	Duplicate Emails	Easy	MySQL, SQLServer	✔️
183	Customers Who Never Order	Easy	MySQL, SQLServer	✔️
184	Department Highest Salary	Medium	MySQL, SQLServer	✔️
185	Department Top Three Salaries	Hard	SQLServer	✔️
186	Reverse Words in a String II	Medium	C#	✔️
187	Repeated DNA Sequences	Medium	C#, JS	✔️
188	Best Time to Buy and Sell Stock IV	Hard	C#	✔️
189	Rotate Array	Medium	C#, Java	✔️
190	Reverse Bits	Easy	C#, Java	✔️
191	Number of 1 Bits	Easy	C#, Java	✔️
192	Word Frequency	Medium		➖
193	Valid Phone Numbers	Easy		➖
194	Transpose File	Medium		➖
195	Tenth Line	Easy		➖
196	Delete Duplicate Emails	Easy	MySQL, SQLServer	✔️
197	Rising Temperature	Easy	MySQL, SQLServer	✔️
198	House Robber	Medium	C#, Java, Python, JS	✔️
199	Binary Tree Right Side View	Medium	C#, Java	✔️
200	Number of Islands	Medium	C#, Java, JS	✔️
201	Bitwise AND of Numbers Range	Medium	C#, Java	✔️
202	Happy Number	Easy	C#, Java, JS	✔️
203	Remove Linked List Elements	Easy	C#, Java, Python, JS	✔️
204	Count Primes	Easy	C#, Java	✔️
205	Isomorphic Strings	Easy	C#, Java	✔️
206	Reverse Linked List	Easy	C#, Java, Python, JS	✔️
207	Course Schedule	Medium	C#, Java, JS	✔️
208	Implement Trie (Prefix Tree)	Medium	C#, Java, Python, JS	✔️
209	Minimum Size Subarray Sum	Medium	C#, Java	✔️
210	Course Schedule II	Medium	C#, JS	✔️
211	Design Add and Search Words Data Structure	Medium	C#, Java, JS	✔️
212	Word Search II	Hard	C#, JS	✔️
213	House Robber II	Medium	C#, Java	✔️
214	Shortest Palindrome	Hard		➖
215	Kth Largest Element in an Array	Medium	C#, Java	✔️
216	Combination Sum III	Medium	C#, Java, JS	✔️
217	Contains Duplicate	Easy	C#	✔️
218	The Skyline Problem	Hard	C#	✔️
219	Contains Duplicate II	Easy	C#, Java, Python, JS	✔️
220	Contains Duplicate III	Medium	C#	✔️
221	Maximal Square	Medium	C#, Java, JS	✔️
222	Count Complete Tree Nodes	Medium	C#, Java, JS	✔️
223	Rectangle Area	Medium	C#	✔️
224	Basic Calculator	Hard	C#, Java, JS	✔️
225	Implement Stack using Queues	Easy	C#, Java	✔️
226	Invert Binary Tree	Easy	C#, Java, Python, JS	✔️
227	Basic Calculator II	Medium	C#, Java, JS	✔️
228	Summary Ranges	Easy	C#, JS	✔️
229	Majority Element II	Medium	C#, Java	✔️
230	Kth Smallest Element in a BST	Medium	C#, Java	✔️
231	Power of Two	Easy	C#, Java, JS	✔️
232	Implement Queue using Stacks	Easy	C#, Java, Python	✔️
233	Number of Digit One	Hard		➖
234	Palindrome Linked List	Easy	C#, Java, Python, JS	✔️
235	Lowest Common Ancestor of a Binary Search Tree	Easy	C#, Java, Python, JS	✔️
236	Lowest Common Ancestor of a Binary Tree	Medium	C#, Java	✔️
237	Delete Node in a Linked List	Easy	C#, Java, JS	✔️
238	Product of Array Except Self	Medium	C#, Java, JS	✔️
239	Sliding Window Maximum	Hard	C#, Java	✔️
240	Search a 2D Matrix II	Medium	C#, Java	✔️
241	Different Ways to Add Parentheses	Medium	C#, Java	✔️
242	Valid Anagram	Easy	C#, Java	✔️
243	Shortest Word Distance	Easy	C#	✔️
244	Shortest Word Distance II	Medium	C#, Java	✔️
245	Shortest Word Distance III	Medium	C#, JS	✔️
246	Strobogrammatic Number	Easy	C#, Java, JS	✔️
247	Strobogrammatic Number II	Medium	C#	✔️
248	Strobogrammatic Number III	Hard		➖
249	Group Shifted Strings	Medium	C#	✔️
250	Count Univalue Subtrees	Medium	C#	✔️
251	Flatten 2D Vector	Medium	C#, Java	✔️
252	Meeting Rooms	Easy	C#	✔️
253	Meeting Rooms II	Medium	C#	✔️
254	Factor Combinations	Medium	C#	✔️
255	Verify Preorder Sequence in Binary Search Tree	Medium	C#	✔️
256	Paint House	Medium	C#, Java	✔️
257	Binary Tree Paths	Easy	C#, Java	✔️
258	Add Digits	Easy	C#, JS	✔️
259	3Sum Smaller	Medium	C#	✔️
260	Single Number III	Medium	C#, JS	✔️
261	Graph Valid Tree	Medium	C#	✔️
262	Trips and Users	Hard	MySQL, SQLServer	✔️
263	Ugly Number	Easy	C#, Java, JS	✔️
264	Ugly Number II	Medium	C#, Java	✔️
265	Paint House II	Hard		➖
266	Palindrome Permutation	Easy	C#, Java, JS	✔️
267	Palindrome Permutation II	Medium	C#	✔️
268	Missing Number	Easy	C#, Java, JS	✔️
269	Alien Dictionary	Hard		➖
270	Closest Binary Search Tree Value	Easy	C#, Java	✔️
271	Encode and Decode Strings	Medium	C#	✔️
272	Closest Binary Search Tree Value II	Hard	Java	✔️
273	Integer to English Words	Hard	C#	✔️
274	H-Index	Medium	C#, Java	✔️
275	H-Index II	Medium	C#, Java	✔️
276	Paint Fence	Medium	C#	✔️
277	Find the Celebrity	Medium	C#	✔️
278	First Bad Version	Easy	C#, Java	✔️
279	Perfect Squares	Medium	C#, Java, Python, JS	✔️
280	Wiggle Sort	Medium	C#, JS	✔️
281	Zigzag Iterator	Medium	C#	✔️
282	Expression Add Operators	Hard		➖
283	Move Zeroes	Easy	C#	✔️
284	Peeking Iterator	Medium	C#, Java	✔️
285	Inorder Successor in BST	Medium	C#, Java	✔️
286	Walls and Gates	Medium	C#	✔️
287	Find the Duplicate Number	Medium	C#, Java	✔️
288	Unique Word Abbreviation	Medium	C#	✔️
289	Game of Life	Medium	C#, Java	✔️
290	Word Pattern	Easy	C#, Java, JS	✔️
291	Word Pattern II	Medium	C#	✔️
292	Nim Game	Easy	C#	✔️
293	Flip Game	Easy	C#	✔️
294	Flip Game II	Medium	C#	✔️
295	Find Median from Data Stream	Hard	C#, Java	✔️
296	Best Meeting Point	Hard	C#	✔️
297	Serialize and Deserialize Binary Tree	Hard	C#, Java	✔️
298	Binary Tree Longest Consecutive Sequence	Medium	C#, JS	✔️
299	Bulls and Cows	Medium	C#, Java	✔️
300	Longest Increasing Subsequence	Medium	C#, Java	✔️
301	Remove Invalid Parentheses	Hard		➖
302	Smallest Rectangle Enclosing Black Pixels	Hard		➖
303	Range Sum Query - Immutable	Easy	C#, Java, Python	✔️
304	Range Sum Query 2D - Immutable	Medium	C#, Java	✔️
305	Number of Islands II	Hard	C#, Java	✔️
306	Additive Number	Medium	C#	✔️
307	Range Sum Query - Mutable	Medium	C#	✔️
308	Range Sum Query 2D - Mutable	Hard		➖
309	Best Time to Buy and Sell Stock with Cooldown	Medium	C#, Java, JS	✔️
310	Minimum Height Trees	Medium	C#, Java, JS	✔️
311	Sparse Matrix Multiplication	Medium	C#, Java	✔️
312	Burst Balloons	Hard	C#, Java, JS	✔️
313	Super Ugly Number	Medium		➖
314	Binary Tree Vertical Order Traversal	Medium	C#, Java	✔️
315	Count of Smaller Numbers After Self	Hard	C#, Java	✔️
316	Remove Duplicate Letters	Medium	C#, Java, JS	✔️
317	Shortest Distance from All Buildings	Hard	C#	✔️
318	Maximum Product of Word Lengths	Medium	C#, JS	✔️
319	Bulb Switcher	Medium	C#	✔️
320	Generalized Abbreviation	Medium	C#	✔️
321	Create Maximum Number	Hard		➖
322	Coin Change	Medium	C#, Java	✔️
323	Number of Connected Components in an Undirected Graph	Medium	C#, Java, JS	✔️
324	Wiggle Sort II	Medium	C#	✔️
325	Maximum Size Subarray Sum Equals k	Medium	C#	✔️
326	Power of Three	Easy	C#, Java, JS	✔️
327	Count of Range Sum	Hard		➖
328	Odd Even Linked List	Medium	C#, Java, JS	✔️
329	Longest Increasing Path in a Matrix	Hard	C#, Java	✔️
330	Patching Array	Hard		➖
331	Verify Preorder Serialization of a Binary Tree	Medium	C#	✔️
332	Reconstruct Itinerary	Hard	C#	✔️
333	Largest BST Subtree	Medium	C#	✔️
334	Increasing Triplet Subsequence	Medium	C#, Java, JS	✔️
335	Self Crossing	Hard		➖
336	Palindrome Pairs	Hard	C#	✔️
337	House Robber III	Medium	C#, JS	✔️
338	Counting Bits	Easy	C#, Java, JS	✔️
339	Nested List Weight Sum	Medium	C#, JS	✔️
340	Longest Substring with At Most K Distinct Characters	Medium	C#, Java	✔️
341	Flatten Nested List Iterator	Medium	C#, Java	✔️
342	Power of Four	Easy	C#, Java, JS	✔️
343	Integer Break	Medium	C#, Java	✔️
344	Reverse String	Easy	C#, Java	✔️
345	Reverse Vowels of a String	Easy	C#, Java	✔️
346	Moving Average from Data Stream	Easy	C#, Java	✔️
347	Top K Frequent Elements	Medium	C#, Java	✔️
348	Design Tic-Tac-Toe	Medium	C#	✔️
349	Intersection of Two Arrays	Easy	C#	✔️
350	Intersection of Two Arrays II	Easy	C#, Java	✔️
351	Android Unlock Patterns	Medium	C#	✔️
352	Data Stream as Disjoint Intervals	Hard	C#	✔️
353	Design Snake Game	Medium	C#	✔️
354	Russian Doll Envelopes	Hard	C#, Java	✔️
355	Design Twitter	Medium	C#, Java	✔️
356	Line Reflection	Medium	C#	✔️
357	Count Numbers with Unique Digits	Medium	C#, Java	✔️
358	Rearrange String k Distance Apart	Hard		➖
359	Logger Rate Limiter	Easy	C#, Java, JS	✔️
360	Sort Transformed Array	Medium	C#	✔️
361	Bomb Enemy	Medium	C#	✔️
362	Design Hit Counter	Medium	C#, Java	✔️
363	Max Sum of Rectangle No Larger Than K	Hard	C#, Java	✔️
364	Nested List Weight Sum II	Medium	C#	✔️
365	Water and Jug Problem	Medium	C#	✔️
366	Find Leaves of Binary Tree	Medium	C#, Java, JS	✔️
367	Valid Perfect Square	Easy	C#	✔️
368	Largest Divisible Subset	Medium	C#, Java, JS	✔️
369	Plus One Linked List	Medium	C#	✔️
370	Range Addition	Medium	C#, Java	✔️
371	Sum of Two Integers	Medium	C#, Java	✔️
372	Super Pow	Medium	C#	✔️
373	Find K Pairs with Smallest Sums	Medium	C#	✔️
374	Guess Number Higher or Lower	Easy	C#, Java, Python, JS	✔️
375	Guess Number Higher or Lower II	Medium		➖
376	Wiggle Subsequence	Medium	C#, Java	✔️
377	Combination Sum IV	Medium	C#, Java, JS	✔️
378	Kth Smallest Element in a Sorted Matrix	Medium	C#, Java, JS	✔️
379	Design Phone Directory	Medium	C#	✔️
380	Insert Delete GetRandom O(1)	Medium	C#, Java, JS	✔️
381	Insert Delete GetRandom O(1) - Duplicates allowed	Hard		➖
382	Linked List Random Node	Medium	C#, Java, JS	✔️
383	Ransom Note	Easy	C#, Java, Python, JS	✔️
384	Shuffle an Array	Medium	C#, Java	✔️
385	Mini Parser	Medium		➖
386	Lexicographical Numbers	Medium	C#	✔️
387	First Unique Character in a String	Easy	C#, Java	✔️
388	Longest Absolute File Path	Medium	C#	✔️
389	Find the Difference	Easy	C#, JS	✔️
390	Elimination Game	Medium	C#, JS	✔️
391	Perfect Rectangle	Hard		➖
392	Is Subsequence	Easy	C#, JS	✔️
393	UTF-8 Validation	Medium	C#	✔️
394	Decode String	Medium	C#, JS	✔️
395	Longest Substring with At Least K Repeating Characters	Medium	C#, JS	✔️
396	Rotate Function	Medium	C#	✔️
397	Integer Replacement	Medium	C#	✔️
398	Random Pick Index	Medium	C#, JS	✔️
399	Evaluate Division	Medium	C#, Java, JS	✔️
400	Nth Digit	Medium	C#, Java	✔️
401	Binary Watch	Easy	C#	✔️
402	Remove K Digits	Medium	C#, JS	✔️
403	Frog Jump	Hard	C#, Java	✔️
404	Sum of Left Leaves	Easy	C#, Java, JS	✔️
405	Convert a Number to Hexadecimal	Easy	C#	✔️
406	Queue Reconstruction by Height	Medium	C#, Java	✔️
407	Trapping Rain Water II	Hard	C#	✔️
408	Valid Word Abbreviation	Easy	C#	✔️
409	Longest Palindrome	Easy	C#	✔️
410	Split Array Largest Sum	Hard	C#	✔️
411	Minimum Unique Word Abbreviation	Hard		➖
412	Fizz Buzz	Easy	C#	✔️
413	Arithmetic Slices	Medium	C#, Java, JS	✔️
414	Third Maximum Number	Easy	C#	✔️
415	Add Strings	Easy	C#, Java	✔️
416	Partition Equal Subset Sum	Medium	C#, Java	✔️
417	Pacific Atlantic Water Flow	Medium	C#, Java, JS	✔️
418	Sentence Screen Fitting	Medium	C#	✔️
419	Battleships in a Board	Medium	C#, JS	✔️
420	Strong Password Checker	Hard		➖
421	Maximum XOR of Two Numbers in an Array	Medium	C#	✔️
422	Valid Word Square	Easy	C#, JS	✔️
423	Reconstruct Original Digits from English	Medium	C#	✔️
424	Longest Repeating Character Replacement	Medium	C#, JS	✔️
425	Word Squares	Hard	C#	✔️
426	Convert Binary Search Tree to Sorted Doubly Linked List	Medium	C#	✔️
427	Construct Quad Tree	Medium	C#, Java	✔️
428	Serialize and Deserialize N-ary Tree	Hard	C#	✔️
429	N-ary Tree Level Order Traversal	Medium	C#, Java, Python, JS	✔️
430	Flatten a Multilevel Doubly Linked List	Medium	C#	✔️
431	Encode N-ary Tree to Binary Tree	Hard	C#	✔️
432	All O one Data Structure	Hard	C#	✔️
433	Minimum Genetic Mutation	Medium	C#, Java, JS	✔️
434	Number of Segments in a String	Easy	C#	✔️
435	Non-overlapping Intervals	Medium	C#, Java, Python	✔️
436	Find Right Interval	Medium	C#, Java	✔️
437	Path Sum III	Medium	C#, Java, Python	✔️
438	Find All Anagrams in a String	Medium	C#, Java, JS	✔️
439	Ternary Expression Parser	Medium	C#, Java	✔️
440	K-th Smallest in Lexicographical Order	Hard		➖
441	Arranging Coins	Easy	C#, JS	✔️
442	Find All Duplicates in an Array	Medium	C#, Java	✔️
443	String Compression	Medium	C#, JS	✔️
444	Sequence Reconstruction	Medium		➖
445	Add Two Numbers II	Medium	C#, Java, Python, JS	✔️
446	Arithmetic Slices II - Subsequence	Hard		➖
447	Number of Boomerangs	Medium	C#	✔️
448	Find All Numbers Disappeared in an Array	Easy	C#, JS	✔️
449	Serialize and Deserialize BST	Medium	C#, Java	✔️
450	Delete Node in a BST	Medium	C#, Java, JS	✔️
451	Sort Characters By Frequency	Medium	C#, Java	✔️
452	Minimum Number of Arrows to Burst Balloons	Medium	C#, Java, JS	✔️
453	Minimum Moves to Equal Array Elements	Easy	C#	✔️
454	4Sum II	Medium	C#, JS	✔️
455	Assign Cookies	Easy	C#	✔️
456	132 Pattern	Medium	C#, Java	✔️
457	Circular Array Loop	Medium	C#, Java	✔️
458	Poor Pigs	Hard	C#	✔️
459	Repeated Substring Pattern	Easy	C#, Java	✔️
460	LFU Cache	Hard		➖
461	Hamming Distance	Easy	C#, Java, JS	✔️
462	Minimum Moves to Equal Array Elements II	Medium	C#, Java	✔️
463	Island Perimeter	Easy	C#, Java	✔️
464	Can I Win	Medium	C#	✔️
465	Optimal Account Balancing	Hard		➖
466	Count The Repetitions	Hard	C#	✔️
467	Unique Substrings in Wraparound String	Medium		➖
468	Validate IP Address	Medium	C#	✔️
469	Convex Polygon	Medium		➖
470	Implement Rand10() Using Rand7()	Medium	C#	✔️
471	Encode String with Shortest Length	Hard		➖
472	Concatenated Words	Hard	C#	✔️
473	Matchsticks to Square	Medium	C#, Java	✔️
474	Ones and Zeroes	Medium	C#	✔️
475	Heaters	Medium	C#, Java	✔️
476	Number Complement	Easy	C#, JS	✔️
477	Total Hamming Distance	Medium	C#, Java	✔️
478	Generate Random Point in a Circle	Medium	C#, Java	✔️
479	Largest Palindrome Product	Hard		➖
480	Sliding Window Median	Hard		➖
481	Magical String	Medium	C#, JS	✔️
482	License Key Formatting	Easy	C#	✔️
483	Smallest Good Base	Hard		➖
484	Find Permutation	Medium	C#	✔️
485	Max Consecutive Ones	Easy	C#, Java	✔️
486	Predict the Winner	Medium	C#	✔️
487	Max Consecutive Ones II	Medium	C#, JS	✔️
488	Zuma Game	Hard	C#	✔️
489	Robot Room Cleaner	Hard		➖
490	The Maze	Medium	C#, Java	✔️
491	Increasing Subsequences	Medium	C#, JS	✔️
492	Construct the Rectangle	Easy	C#	✔️
493	Reverse Pairs	Hard		➖
494	Target Sum	Medium	C#, Java	✔️
495	Teemo Attacking	Easy	C#, JS	✔️
496	Next Greater Element I	Easy	C#, Java, Python, JS	✔️
497	Random Point in Non-overlapping Rectangles	Medium	C#	✔️
498	Diagonal Traverse	Medium	C#, Java	✔️
499	The Maze III	Hard		➖
500	Keyboard Row	Easy	C#	✔️
501	Find Mode in Binary Search Tree	Easy	C#, Java, JS	✔️
502	IPO	Hard	C#, Java	✔️
503	Next Greater Element II	Medium	C#, Java, Python, JS	✔️
504	Base 7	Easy	C#, JS	✔️
505	The Maze II	Medium	C#, Java, JS	✔️
506	Relative Ranks	Easy	C#, Java, JS	✔️
507	Perfect Number	Easy	C#, JS	✔️
508	Most Frequent Subtree Sum	Medium	C#, Java	✔️
509	Fibonacci Number	Easy	C#, Java	✔️
510	Inorder Successor in BST II	Medium	C#	✔️
511	Game Play Analysis I	Easy	MySQL, SQLServer	✔️
512	Game Play Analysis II	Easy	MySQL, SQLServer	✔️
513	Find Bottom Left Tree Value	Medium	C#	✔️
514	Freedom Trail	Hard		➖
515	Find Largest Value in Each Tree Row	Medium	C#, Java, JS	✔️
516	Longest Palindromic Subsequence	Medium	C#, JS	✔️
517	Super Washing Machines	Hard	C#	✔️
518	Coin Change 2	Medium	C#	✔️
519	Random Flip Matrix	Medium		➖
520	Detect Capital	Easy	C#, Java, JS	✔️
521	Longest Uncommon Subsequence I	Easy	C#, JS	✔️
522	Longest Uncommon Subsequence II	Medium		➖
523	Continuous Subarray Sum	Medium	C#, JS	✔️
524	Longest Word in Dictionary through Deleting	Medium	C#, Java	✔️
525	Contiguous Array	Medium	C#, Java, JS	✔️
526	Beautiful Arrangement	Medium	C#	✔️
527	Word Abbreviation	Hard		➖
528	Random Pick with Weight	Medium	C#, Java	✔️
529	Minesweeper	Medium	C#, Java	✔️
530	Minimum Absolute Difference in BST	Easy	C#, Java	✔️
531	Lonely Pixel I	Medium	C#	✔️
532	K-diff Pairs in an Array	Medium	C#, JS	✔️
533	Lonely Pixel II	Medium	C#	✔️
534	Game Play Analysis III	Medium	MySQL, SQLServer	✔️
535	Encode and Decode TinyURL	Medium	C#, Java	✔️
536	Construct Binary Tree from String	Medium	C#, Java	✔️
537	Complex Number Multiplication	Medium	C#, Java, JS	✔️
538	Convert BST to Greater Tree	Medium	C#, Java	✔️
539	Minimum Time Difference	Medium	C#, JS	✔️
540	Single Element in a Sorted Array	Medium	C#, Java, Python, JS	✔️
541	Reverse String II	Easy	C#	✔️
542	01 Matrix	Medium	C#, Java, JS	✔️
543	Diameter of Binary Tree	Easy	C#, Java, Python	✔️
544	Output Contest Matches	Medium	C#	✔️
545	Boundary of Binary Tree	Medium	C#	✔️
546	Remove Boxes	Hard	C#	✔️
547	Number of Provinces	Medium	C#, Java	✔️
548	Split Array with Equal Sum	Medium		➖
549	Binary Tree Longest Consecutive Sequence II	Medium	C#, JS	✔️
550	Game Play Analysis IV	Medium	MySQL, SQLServer	✔️
551	Student Attendance Record I	Easy	C#	✔️
552	Student Attendance Record II	Hard		➖
553	Optimal Division	Medium	C#, JS	✔️
554	Brick Wall	Medium	C#, Java	✔️
555	Split Concatenated Strings	Medium	C#	✔️
556	Next Greater Element III	Medium	C#, Java	✔️
557	Reverse Words in a String III	Easy	C#, JS	✔️
558	Logical OR of Two Binary Grids Represented as Quad-Trees	Medium	C#	✔️
559	Maximum Depth of N-ary Tree	Easy	C#, Java	✔️
560	Subarray Sum Equals K	Medium	C#, JS	✔️
561	Array Partition I	Easy	C#	✔️
562	Longest Line of Consecutive One in Matrix	Medium	C#	✔️
563	Binary Tree Tilt	Easy	C#, Java, JS	✔️
564	Find the Closest Palindrome	Hard	C#	✔️
565	Array Nesting	Medium	C#, Java	✔️
566	Reshape the Matrix	Easy	C#, Java, Python	✔️
567	Permutation in String	Medium	C#, Java, JS	✔️
568	Maximum Vacation Days	Hard		➖
569	Median Employee Salary	Hard	MySQL, SQLServer	✔️
570	Managers with at Least 5 Direct Reports	Medium	MySQL, SQLServer	✔️
571	Find Median Given Frequency of Numbers	Hard	SQLServer	✔️
572	Subtree of Another Tree	Easy	C#, Java	✔️
573	Squirrel Simulation	Medium	C#	✔️
574	Winning Candidate	Medium	MySQL, SQLServer	✔️
575	Distribute Candies	Easy	C#, Java	✔️
576	Out of Boundary Paths	Medium	C#, Java	✔️
577	Employee Bonus	Easy	MySQL, SQLServer	✔️
578	Get Highest Answer Rate Question	Medium	MySQL, SQLServer	✔️
579	Find Cumulative Salary of an Employee	Hard	MySQL, SQLServer	✔️
580	Count Student Number in Departments	Medium	MySQL, SQLServer	✔️
581	Shortest Unsorted Continuous Subarray	Medium	C#, Java, Python	✔️
582	Kill Process	Medium	C#, Java	✔️
583	Delete Operation for Two Strings	Medium	C#, Java	✔️
584	Find Customer Referee	Easy	MySQL, SQLServer	✔️
585	Investments in 2016	Medium	MySQL, SQLServer	✔️
586	Customer Placing the Largest Number of Orders	Easy	MySQL, SQLServer	✔️
587	Erect the Fence	Hard	C#	✔️
588	Design In-Memory File System	Hard	C#	✔️
589	N-ary Tree Preorder Traversal	Easy	C#, Java, JS	✔️
590	N-ary Tree Postorder Traversal	Easy	C#, Java, JS	✔️
591	Tag Validator	Hard		➖
592	Fraction Addition and Subtraction	Medium	C#	✔️
593	Valid Square	Medium	C#	✔️
594	Longest Harmonious Subsequence	Easy	C#, Java, JS	✔️
595	Big Countries	Easy	MySQL, SQLServer	✔️
596	Classes More Than 5 Students	Easy	MySQL, SQLServer	✔️
597	Friend Requests I: Overall Acceptance Rate	Easy	MySQL, SQLServer	✔️
598	Range Addition II	Easy	C#	✔️
599	Minimum Index Sum of Two Lists	Easy	C#, JS	✔️
600	Non-negative Integers without Consecutive Ones	Hard		➖
601	Human Traffic of Stadium	Hard	MySQL, SQLServer	✔️
602	Friend Requests II: Who Has the Most Friends	Medium	MySQL, SQLServer	✔️
603	Consecutive Available Seats	Easy	MySQL, SQLServer	✔️
604	Design Compressed String Iterator	Easy	C#	✔️
605	Can Place Flowers	Easy	C#, Java, JS	✔️
606	Construct String from Binary Tree	Easy	C#, Java, JS	✔️
607	Sales Person	Easy	MySQL, SQLServer	✔️
608	Tree Node	Medium	MySQL, SQLServer	✔️
609	Find Duplicate File in System	Medium	C#	✔️
610	Triangle Judgement	Easy	MySQL, SQLServer	✔️
611	Valid Triangle Number	Medium	C#, Java, Python	✔️
612	Shortest Distance in a Plane	Medium	MySQL, SQLServer	✔️
613	Shortest Distance in a Line	Easy	MySQL, SQLServer	✔️
614	Second Degree Follower	Medium	MySQL, SQLServer	✔️
615	Average Salary: Departments VS Company	Hard	MySQL, SQLServer	✔️
616	Add Bold Tag in String	Medium	C#	✔️
617	Merge Two Binary Trees	Easy	C#, Java	✔️
618	Students Report By Geography	Hard	MySQL, SQLServer	✔️
619	Biggest Single Number	Easy	MySQL, SQLServer	✔️
620	Not Boring Movies	Easy	MySQL, SQLServer	✔️
621	Task Scheduler	Medium	C#, Java	✔️
622	Design Circular Queue	Medium	C#, Java	✔️
623	Add One Row to Tree	Medium	C#, Java, JS	✔️
624	Maximum Distance in Arrays	Medium	C#	✔️
625	Minimum Factorization	Medium	C#	✔️
626	Exchange Seats	Medium	MySQL, SQLServer	✔️
627	Swap Salary	Easy	MySQL, SQLServer	✔️
628	Maximum Product of Three Numbers	Easy	C#, Java	✔️
629	K Inverse Pairs Array	Hard		➖
630	Course Schedule III	Hard	C#, Java	✔️
631	Design Excel Sum Formula	Hard		➖
632	Smallest Range Covering Elements from K Lists	Hard		➖
633	Sum of Square Numbers	Medium	C#, Java, JS	✔️
634	Find the Derangement of An Array	Medium	C#	✔️
635	Design Log Storage System	Medium	C#	✔️
636	Exclusive Time of Functions	Medium	C#	✔️
637	Average of Levels in Binary Tree	Easy	C#, Java, JS	✔️
638	Shopping Offers	Medium	C#	✔️
639	Decode Ways II	Hard	C#	✔️
640	Solve the Equation	Medium	C#, Java, JS	✔️
641	Design Circular Deque	Medium	C#, Java	✔️
642	Design Search Autocomplete System	Hard		➖
643	Maximum Average Subarray I	Easy	C#	✔️
644	Maximum Average Subarray II	Hard		➖
645	Set Mismatch	Easy	C#, Java	✔️
646	Maximum Length of Pair Chain	Medium	C#, Java	✔️
647	Palindromic Substrings	Medium	C#, Java	✔️
648	Replace Words	Medium	C#	✔️
649	Dota2 Senate	Medium	C#, Java	✔️
650	2 Keys Keyboard	Medium	C#	✔️
651	4 Keys Keyboard	Medium	C#	✔️
652	Find Duplicate Subtrees	Medium	C#, Java, JS	✔️
653	Two Sum IV - Input is a BST	Easy	C#, Java, Python, JS	✔️
654	Maximum Binary Tree	Medium	C#, Java	✔️
655	Print Binary Tree	Medium	C#, JS	✔️
656	Coin Path	Hard		➖
657	Robot Return to Origin	Easy	C#	✔️
658	Find K Closest Elements	Medium	C#, Java	✔️
659	Split Array into Consecutive Subsequences	Medium	C#	✔️
660	Remove 9	Hard		➖
661	Image Smoother	Easy	C#, Java	✔️
662	Maximum Width of Binary Tree	Medium	C#, Java	✔️
663	Equal Tree Partition	Medium	C#, Java	✔️
664	Strange Printer	Hard	C#	✔️
665	Non-decreasing Array	Medium	C#, Java	✔️
666	Path Sum IV	Medium	C#	✔️
667	Beautiful Arrangement II	Medium	C#, Java, JS	✔️
668	Kth Smallest Number in Multiplication Table	Hard	C#	✔️
669	Trim a Binary Search Tree	Medium	C#, Java	✔️
670	Maximum Swap	Medium	C#, JS	✔️
671	Second Minimum Node In a Binary Tree	Easy	C#, Java, Python	✔️
672	Bulb Switcher II	Medium		➖
673	Number of Longest Increasing Subsequence	Medium	C#	✔️
674	Longest Continuous Increasing Subsequence	Easy	C#	✔️
675	Cut Off Trees for Golf Event	Hard	C#	✔️
676	Implement Magic Dictionary	Medium	C#, Java	✔️
677	Map Sum Pairs	Medium	C#, Java	✔️
678	Valid Parenthesis String	Medium	C#	✔️
679	24 Game	Hard	C#	✔️
680	Valid Palindrome II	Easy	C#	✔️
681	Next Closest Time	Medium	C#	✔️
682	Baseball Game	Easy	C#, Java, JS	✔️
683	K Empty Slots	Hard		➖
684	Redundant Connection	Medium	C#, Java	✔️
685	Redundant Connection II	Hard		➖
686	Repeated String Match	Medium	C#, JS	✔️
687	Longest Univalue Path	Medium	C#, JS	✔️
688	Knight Probability in Chessboard	Medium	C#, Java	✔️
689	Maximum Sum of 3 Non-Overlapping Subarrays	Hard	C#	✔️
690	Employee Importance	Easy	C#, Java	✔️
691	Stickers to Spell Word	Hard		➖
692	Top K Frequent Words	Medium	C#, Java, JS	✔️
693	Binary Number with Alternating Bits	Easy	C#, Java	✔️
694	Number of Distinct Islands	Medium	C#, Java	✔️
695	Max Area of Island	Medium	C#, Java	✔️
696	Count Binary Substrings	Easy	C#, Java	✔️
697	Degree of an Array	Easy	C#	✔️
698	Partition to K Equal Sum Subsets	Medium	C#, JS	✔️
699	Falling Squares	Hard	C#	✔️
700	Search in a Binary Search Tree	Easy	C#, Java, Python	✔️
701	Insert into a Binary Search Tree	Medium	C#, Java, Python, JS	✔️
702	Search in a Sorted Array of Unknown Size	Medium	C#	✔️
703	Kth Largest Element in a Stream	Easy	C#, Java	✔️
704	Binary Search	Easy	C#, Java, JS	✔️
705	Design HashSet	Easy	C#, Java	✔️
706	Design HashMap	Easy	C#, Java	✔️
707	Design Linked List	Medium	C#, Java	✔️
708	Insert into a Sorted Circular Linked List	Medium	C#	✔️
709	To Lower Case	Easy	C#	✔️
710	Random Pick with Blacklist	Hard	C#	✔️
711	Number of Distinct Islands II	Hard		➖
712	Minimum ASCII Delete Sum for Two Strings	Medium	C#, Java	✔️
713	Subarray Product Less Than K	Medium	C#, Java	✔️
714	Best Time to Buy and Sell Stock with Transaction Fee	Medium	C#, Java	✔️
715	Range Module	Hard		➖
716	Max Stack	Easy	C#, JS	✔️
717	1-bit and 2-bit Characters	Easy	C#, JS	✔️
718	Maximum Length of Repeated Subarray	Medium	C#	✔️
719	Find K-th Smallest Pair Distance	Hard	C#, Java	✔️
720	Longest Word in Dictionary	Medium	C#, Java	✔️
721	Accounts Merge	Medium	C#, Java	✔️
722	Remove Comments	Medium	C#	✔️
723	Candy Crush	Medium	C#, Java	✔️
724	Find Pivot Index	Easy	C#	✔️
725	Split Linked List in Parts	Medium	C#, Java	✔️
726	Number of Atoms	Hard	C#	✔️
727	Minimum Window Subsequence	Hard		➖
728	Self Dividing Numbers	Easy	C#, Java	✔️
729	My Calendar I	Medium	C#, Java	✔️
730	Count Different Palindromic Subsequences	Hard		➖
731	My Calendar II	Medium	C#	✔️
732	My Calendar III	Hard	C#	✔️
733	Flood Fill	Easy	C#, Java	✔️
734	Sentence Similarity	Easy	C#, JS	✔️
735	Asteroid Collision	Medium	C#, Java, JS	✔️
736	Parse Lisp Expression	Hard		➖
737	Sentence Similarity II	Medium	C#, JS	✔️
738	Monotone Increasing Digits	Medium	C#	✔️
739	Daily Temperatures	Medium	C#, Java, JS	✔️
740	Delete and Earn	Medium	C#, Java, JS	✔️
741	Cherry Pickup	Hard		➖
742	Closest Leaf in a Binary Tree	Medium	C#	✔️
743	Network Delay Time	Medium	C#, Java, JS	✔️
744	Find Smallest Letter Greater Than Target	Easy	C#, Java	✔️
745	Prefix and Suffix Search	Hard	C#, Java	✔️
746	Min Cost Climbing Stairs	Easy	C#, Java	✔️
747	Largest Number At Least Twice of Others	Easy	C#, JS	✔️
748	Shortest Completing Word	Easy	C#	✔️
749	Contain Virus	Hard		➖
750	Number Of Corner Rectangles	Medium	C#	✔️
751	IP to CIDR	Medium		➖
752	Open the Lock	Medium	C#, Java	✔️
753	Cracking the Safe	Hard		➖
754	Reach a Number	Medium	C#	✔️
755	Pour Water	Medium	C#	✔️
756	Pyramid Transition Matrix	Medium	C#	✔️
757	Set Intersection Size At Least Two	Hard		➖
758	Bold Words in String	Medium	C#	✔️
759	Employee Free Time	Hard	C#	✔️
760	Find Anagram Mappings	Easy	C#, Java	✔️
761	Special Binary String	Hard		➖
762	Prime Number of Set Bits in Binary Representation	Easy	C#, JS	✔️
763	Partition Labels	Medium	C#, Java	✔️
764	Largest Plus Sign	Medium	C#	✔️
765	Couples Holding Hands	Hard		➖
766	Toeplitz Matrix	Easy	C#, JS	✔️
767	Reorganize String	Medium	C#, Java	✔️
768	Max Chunks To Make Sorted II	Hard		➖
769	Max Chunks To Make Sorted	Medium	C#	✔️
770	Basic Calculator IV	Hard		➖
771	Jewels and Stones	Easy	C#	✔️
772	Basic Calculator III	Hard	C#	✔️
773	Sliding Puzzle	Hard	C#	✔️
774	Minimize Max Distance to Gas Station	Hard		➖
775	Global and Local Inversions	Medium	C#, Java	✔️
776	Split BST	Medium	C#	✔️
777	Swap Adjacent in LR String	Medium		➖
778	Swim in Rising Water	Hard	C#, Java	✔️
779	K-th Symbol in Grammar	Medium	C#, Java, JS	✔️
780	Reaching Points	Hard	C#	✔️
781	Rabbits in Forest	Medium	C#, Java	✔️
782	Transform to Chessboard	Hard		➖
783	Minimum Distance Between BST Nodes	Easy	C#, JS	✔️
784	Letter Case Permutation	Medium	C#, Java	✔️
785	Is Graph Bipartite?	Medium	C#, Java	✔️
786	K-th Smallest Prime Fraction	Hard	C#, Java	✔️
787	Cheapest Flights Within K Stops	Medium	C#, Java, JS	✔️
788	Rotated Digits	Easy	C#	✔️
789	Escape The Ghosts	Medium	C#	✔️
790	Domino and Tromino Tiling	Medium	C#	✔️
791	Custom Sort String	Medium	C#	✔️
792	Number of Matching Subsequences	Medium	C#, Java	✔️
793	Preimage Size of Factorial Zeroes Function	Hard		➖
794	Valid Tic-Tac-Toe State	Medium	C#	✔️
795	Number of Subarrays with Bounded Maximum	Medium	C#, Java	✔️
796	Rotate String	Easy	C#, Java	✔️
797	All Paths From Source to Target	Medium	C#, Java, JS	✔️
798	Smallest Rotation with Highest Score	Hard	C#	✔️
799	Champagne Tower	Medium	C#, Java	✔️
800	Similar RGB Color	Easy	C#	✔️
801	Minimum Swaps To Make Sequences Increasing	Hard	C#	✔️
802	Find Eventual Safe States	Medium	C#, Java	✔️
803	Bricks Falling When Hit	Hard
804	Unique Morse Code Words	Easy	C#, Java	✔️
805	Split Array With Same Average	Hard		➖
806	Number of Lines To Write String	Easy	C#	✔️
807	Max Increase to Keep City Skyline	Medium	C#	✔️
808	Soup Servings	Medium		➖
809	Expressive Words	Medium	C#	✔️
810	Chalkboard XOR Game	Hard		➖
811	Subdomain Visit Count	Medium	C#, JS	✔️
812	Largest Triangle Area	Easy	C#	✔️
813	Largest Sum of Averages	Medium	C#	✔️
814	Binary Tree Pruning	Medium	C#, Java, Python, JS	✔️
815	Bus Routes	Hard	C#	✔️
816	Ambiguous Coordinates	Medium	C#	✔️
817	Linked List Components	Medium	C#, Java, JS	✔️
818	Race Car	Hard		➖
819	Most Common Word	Easy	C#	✔️
820	Short Encoding of Words	Medium	C#, Java	✔️
821	Shortest Distance to a Character	Easy	C#	✔️
822	Card Flipping Game	Medium	C#	✔️
823	Binary Trees With Factors	Medium	C#, Java, JS	✔️
824	Goat Latin	Easy	C#	✔️
825	Friends Of Appropriate Ages	Medium	C#, JS	✔️
826	Most Profit Assigning Work	Medium	C#	✔️
827	Making A Large Island	Hard	C#, Java	✔️
828	Count Unique Characters of All Substrings of a Given String	Hard	C#	✔️
829	Consecutive Numbers Sum	Hard	C#	✔️
830	Positions of Large Groups	Easy	C#	✔️
831	Masking Personal Information	Medium	C#	✔️
832	Flipping an Image	Easy	C#, Java, Python	✔️
833	Find And Replace in String	Medium	C#	✔️
834	Sum of Distances in Tree	Hard	C#	✔️
835	Image Overlap	Medium	C#, JS	✔️
836	Rectangle Overlap	Easy	C#	✔️
837	New 21 Game	Medium	C#	✔️
838	Push Dominoes	Medium	C#, Java, JS	✔️
839	Similar String Groups	Hard	C#	✔️
840	Magic Squares In Grid	Medium	C#	✔️
841	Keys and Rooms	Medium	C#, Java, JS	✔️
842	Split Array into Fibonacci Sequence	Medium	C#	✔️
843	Guess the Word	Hard		➖
844	Backspace String Compare	Easy	C#	✔️
845	Longest Mountain in Array	Medium	C#	✔️
846	Hand of Straights	Medium	C#, JS	✔️
847	Shortest Path Visiting All Nodes	Hard	C#, Java, JS	✔️
848	Shifting Letters	Medium	C#, Java	✔️
849	Maximize Distance to Closest Person	Medium	C#, JS	✔️
850	Rectangle Area II	Hard		➖
851	Loud and Rich	Medium	C#, JS	✔️
852	Peak Index in a Mountain Array	Easy	C#, Java	✔️
853	Car Fleet	Medium	C#, Java	✔️
854	K-Similar Strings	Hard	C#	✔️
855	Exam Room	Medium	C#	✔️
856	Score of Parentheses	Medium	C#, Java, Python, JS	✔️
857	Minimum Cost to Hire K Workers	Hard	C#	✔️
858	Mirror Reflection	Medium	C#	✔️
859	Buddy Strings	Easy	C#, Java	✔️
860	Lemonade Change	Easy	C#	✔️
861	Score After Flipping Matrix	Medium	C#	✔️
862	Shortest Subarray with Sum at Least K	Hard		➖
863	All Nodes Distance K in Binary Tree	Medium	C#, Java	✔️
864	Shortest Path to Get All Keys	Hard	C#	✔️
865	Smallest Subtree with all the Deepest Nodes	Medium	C#	✔️
866	Prime Palindrome	Medium		➖
867	Transpose Matrix	Easy	C#	✔️
868	Binary Gap	Easy	C#	✔️
869	Reordered Power of 2	Medium	C#, Java, JS	✔️
870	Advantage Shuffle	Medium	C#, Java	✔️
871	Minimum Number of Refueling Stops	Hard	C#, Java, JS	✔️
872	Leaf-Similar Trees	Easy	C#, Java	✔️
873	Length of Longest Fibonacci Subsequence	Medium	C#	✔️
874	Walking Robot Simulation	Easy	C#	✔️
875	Koko Eating Bananas	Medium	C#, Java, Python, JS	✔️
876	Middle of the Linked List	Easy	C#, Java, JS	✔️
877	Stone Game	Medium	C#, Java, Python	✔️
878	Nth Magical Number	Hard	C#, JS	✔️
879	Profitable Schemes	Hard	C#	✔️
880	Decoded String at Index	Medium	C#, Java	✔️
881	Boats to Save People	Medium	C#, Java, Python, JS	✔️
882	Reachable Nodes In Subdivided Graph	Hard		➖
883	Projection Area of 3D Shapes	Easy	C#	✔️
884	Uncommon Words from Two Sentences	Easy	C#	✔️
885	Spiral Matrix III	Medium	C#	✔️
886	Possible Bipartition	Medium	C#	✔️
887	Super Egg Drop	Hard		➖
888	Fair Candy Swap	Easy	C#, Java	✔️
889	Construct Binary Tree from Preorder and Postorder Traversal	Medium	C#	✔️
890	Find and Replace Pattern	Medium	C#, Java	✔️
891	Sum of Subsequence Widths	Hard		➖
892	Surface Area of 3D Shapes	Easy	C#	✔️
893	Groups of Special-Equivalent Strings	Easy	C#	✔️
894	All Possible Full Binary Trees	Medium	C#	✔️
895	Maximum Frequency Stack	Hard	C#	✔️
896	Monotonic Array	Easy	C#, Java	✔️
897	Increasing Order Search Tree	Easy	C#, Java	✔️
898	Bitwise ORs of Subarrays	Medium		➖
899	Orderly Queue	Hard	C#, Java, JS	✔️
900	RLE Iterator	Medium	C#	✔️
901	Online Stock Span	Medium	C#, JS	✔️
902	Numbers At Most N Given Digit Set	Hard	C#	✔️
903	Valid Permutations for DI Sequence	Hard		➖
904	Fruit Into Baskets	Medium	C#, Java, Python, JS	✔️
905	Sort Array By Parity	Easy	C#	✔️
906	Super Palindromes	Hard	C#	✔️
907	Sum of Subarray Minimums	Medium	C#, Java, JS	✔️
908	Smallest Range I	Easy	C#	✔️
909	Snakes and Ladders	Medium	C#, Java	✔️
910	Smallest Range II	Medium	C#	✔️
911	Online Election	Medium	C#	✔️
912	Sort an Array	Medium	C#, Java	✔️
913	Cat and Mouse	Hard	C#, Java	✔️
914	X of a Kind in a Deck of Cards	Easy	C#, Java	✔️
915	Partition Array into Disjoint Intervals	Medium	C#, JS	✔️
916	Word Subsets	Medium	C#, Java	✔️
917	Reverse Only Letters	Easy	C#, JS	✔️
918	Maximum Sum Circular Subarray	Medium	C#, JS	✔️
919	Complete Binary Tree Inserter	Medium	C#	✔️
920	Number of Music Playlists	Hard		➖
921	Minimum Add to Make Parentheses Valid	Medium	C#, JS	✔️
922	Sort Array By Parity II	Easy	C#	✔️
923	3Sum With Multiplicity	Medium	C#, Java	✔️
924	Minimize Malware Spread	Hard		➖
925	Long Pressed Name	Easy	C#	✔️
926	Flip String to Monotone Increasing	Medium	C#, Java, JS	✔️
927	Three Equal Parts	Hard	C#	✔️
928	Minimize Malware Spread II	Hard		➖
929	Unique Email Addresses	Easy	C#	✔️
930	Binary Subarrays With Sum	Medium	C#, Python, JS	✔️
931	Minimum Falling Path Sum	Medium	C#, JS	✔️
932	Beautiful Array	Medium	C#	✔️
933	Number of Recent Calls	Easy	C#, Java	✔️
934	Shortest Bridge	Medium	C#, Java, JS	✔️
935	Knight Dialer	Medium	C#, Java	✔️
936	Stamping The Sequence	Hard	C#	✔️
937	Reorder Data in Log Files	Easy	C#	✔️
938	Range Sum of BST	Easy	C#, Java, JS	✔️
939	Minimum Area Rectangle	Medium	C#	✔️
940	Distinct Subsequences II	Hard		➖
941	Valid Mountain Array	Easy	C#, JS	✔️
942	DI String Match	Easy	C#	✔️
943	Find the Shortest Superstring	Hard		➖
944	Delete Columns to Make Sorted	Easy	C#, JS	✔️
945	Minimum Increment to Make Array Unique	Medium	C#	✔️
946	Validate Stack Sequences	Medium	C#, Java, JS	✔️
947	Most Stones Removed with Same Row or Column	Medium	C#, JS	✔️
948	Bag of Tokens	Medium	C#, JS	✔️
949	Largest Time for Given Digits	Medium	C#	✔️
950	Reveal Cards In Increasing Order	Medium	C#	✔️
951	Flip Equivalent Binary Trees	Medium	C#	✔️
952	Largest Component Size by Common Factor	Hard	C#	✔️
953	Verifying an Alien Dictionary	Easy	C#, Java	✔️
954	Array of Doubled Pairs	Medium	C#, Java	✔️
955	Delete Columns to Make Sorted II	Medium	C#	✔️
956	Tallest Billboard	Hard	C#	✔️
957	Prison Cells After N Days	Medium	C#, Java	✔️
958	Check Completeness of a Binary Tree	Medium	C#, JS	✔️
959	Regions Cut By Slashes	Medium		➖
960	Delete Columns to Make Sorted III	Hard		➖
961	N-Repeated Element in Size 2N Array	Easy	C#	✔️
962	Maximum Width Ramp	Medium	C#	✔️
963	Minimum Area Rectangle II	Medium		➖
964	Least Operators to Express Number	Hard		➖
965	Univalued Binary Tree	Easy	C#, Java	✔️
966	Vowel Spellchecker	Medium	C#, Java	✔️
967	Numbers With Same Consecutive Differences	Medium	C#, JS	✔️
968	Binary Tree Cameras	Hard	C#, Java	✔️
969	Pancake Sorting	Medium	C#, JS	✔️
970	Powerful Integers	Medium	C#, Java	✔️
971	Flip Binary Tree To Match Preorder Traversal	Medium	C#	✔️
972	Equal Rational Numbers	Hard		➖
973	K Closest Points to Origin	Medium	C#, Java	✔️
974	Subarray Sums Divisible by K	Medium	C#, Java, JS	✔️
975	Odd Even Jump	Hard		➖
976	Largest Perimeter Triangle	Easy	C#, JS	✔️
977	Squares of a Sorted Array	Easy	C#	✔️
978	Longest Turbulent Subarray	Medium	C#	✔️
979	Distribute Coins in Binary Tree	Medium	C#, Java	✔️
980	Unique Paths III	Hard	C#, Java, JS	✔️
981	Time Based Key-Value Store	Medium	C#, Java, JS	✔️
982	Triples with Bitwise AND Equal To Zero	Hard		➖
983	Minimum Cost For Tickets	Medium	C#, Java, JS	✔️
984	String Without AAA or BBB	Medium	C#	✔️
985	Sum of Even Numbers After Queries	Easy	C#, JS	✔️
986	Interval List Intersections	Medium	C#, Java	✔️
987	Vertical Order Traversal of a Binary Tree	Hard	C#, Java	✔️
988	Smallest String Starting From Leaf	Medium	C#, Java	✔️
989	Add to Array-Form of Integer	Easy	C#, Java, JS	✔️
990	Satisfiability of Equality Equations	Medium	C#	✔️
991	Broken Calculator	Medium	C#, Java, JS	✔️
992	Subarrays with K Different Integers	Hard	C#, JS	✔️
993	Cousins in Binary Tree	Easy	C#, Java, Python	✔️
994	Rotting Oranges	Medium	C#, Java, JS	✔️
995	Minimum Number of K Consecutive Bit Flips	Hard		➖
996	Number of Squareful Arrays	Hard		➖
997	Find the Town Judge	Easy	C#, Java, JS	✔️
998	Maximum Binary Tree II	Medium	C#, Java	✔️
999	Available Captures for Rook	Easy	C#, Java	✔️
1000	Minimum Cost to Merge Stones	Hard		➖
1001	Grid Illumination	Hard	C#	✔️
1002	Find Common Characters	Easy	C#	✔️
1003	Check If Word Is Valid After Substitutions	Medium	C#	✔️
1004	Max Consecutive Ones III	Medium	C#, Java	✔️
1005	Maximize Sum Of Array After K Negations	Easy	C#, JS	✔️
1006	Clumsy Factorial	Medium	C#, Java	✔️
1007	Minimum Domino Rotations For Equal Row	Medium	C#, Java	✔️
1008	Construct Binary Search Tree from Preorder Traversal	Medium	C#, Java	✔️
1009	Complement of Base 10 Integer	Easy	C#, Java	✔️
1010	Pairs of Songs With Total Durations Divisible by 60	Medium	C#, Java, JS	✔️
1011	Capacity To Ship Packages Within D Days	Medium	C#, Java, JS	✔️
1012	Numbers With Repeated Digits	Hard		➖
1013	Partition Array Into Three Parts With Equal Sum	Easy	C#	✔️
1014	Best Sightseeing Pair	Medium	C#	✔️
1015	Smallest Integer Divisible by K	Medium	C#, JS	✔️
1016	Binary String With Substrings Representing 1 To N	Medium	C#	✔️
1017	Convert to Base -2	Medium	C#	✔️
1018	Binary Prefix Divisible By 5	Easy	C#	✔️
1019	Next Greater Node In Linked List	Medium	C#	✔️
1020	Number of Enclaves	Medium	C#, JS	✔️
1021	Remove Outermost Parentheses	Easy	C#, Java	✔️
1022	Sum of Root To Leaf Binary Numbers	Easy	C#, Java, JS	✔️
1023	Camelcase Matching	Medium	C#	✔️
1024	Video Stitching	Medium	C#	✔️
1025	Divisor Game	Easy	C#	✔️
1026	Maximum Difference Between Node and Ancestor	Medium	C#, JS, Java	✔️
1027	Longest Arithmetic Subsequence	Medium	C#	✔️
1028	Recover a Tree From Preorder Traversal	Hard	C#	✔️
1029	Two City Scheduling	Medium	C#, Java	✔️
1030	Matrix Cells in Distance Order	Easy	C#, Java	✔️
1031	Maximum Sum of Two Non-Overlapping Subarrays	Medium	C#	✔️
1032	Stream of Characters	Hard	C#	✔️
1033	Moving Stones Until Consecutive	Easy	C#	✔️
1034	Coloring A Border	Medium	C#, JS	✔️
1035	Uncrossed Lines	Medium	C#, Java	✔️
1036	Escape a Large Maze	Hard	C#	✔️
1037	Valid Boomerang	Easy	C#	✔️
1038	Binary Search Tree to Greater Sum Tree	Medium	C#, Java	✔️
1039	Minimum Score Triangulation of Polygon	Medium		➖
1040	Moving Stones Until Consecutive II	Medium		➖
1041	Robot Bounded In Circle	Medium	C#, Java, JS	✔️
1042	Flower Planting With No Adjacent	Medium	C#	✔️
1043	Partition Array for Maximum Sum	Medium	C#	✔️
1044	Longest Duplicate Substring	Hard		〽️
1045	Customers Who Bought All Products	Medium	MySQL, SQLServer	✔️
1046	Last Stone Weight	Easy	C#, Java	✔️
1047	Remove All Adjacent Duplicates In String	Easy	C#, Java	✔️
1048	Longest String Chain	Medium	C#, Java	✔️
1049	Last Stone Weight II	Medium	C#	✔️
1050	Actors and Directors Who Cooperated At Least Three Times	Easy	MySQL, SQLServer	✔️
1051	Height Checker	Easy	C#, Java	✔️
1052	Grumpy Bookstore Owner	Medium	C#, Java	✔️
1053	Previous Permutation With One Swap	Medium	C#	✔️
1054	Distant Barcodes	Medium	C#	✔️
1055	Shortest Way to Form String	Medium	C#, JS	✔️
1056	Confusing Number	Easy	C#, Java	✔️
1057	Campus Bikes	Medium	C#	✔️
1058	Minimize Rounding Error to Meet Target	Medium	C#	✔️
1059	All Paths from Source Lead to Destination	Medium	C#, Java	✔️
1060	Missing Element in Sorted Array	Medium	C#	✔️
1061	Lexicographically Smallest Equivalent String	Medium	C#, Java	✔️
1062	Longest Repeating Substring	Medium	C#	✔️
1063	Number of Valid Subarrays	Hard		➖
1064	Fixed Point	Easy	C#	✔️
1065	Index Pairs of a String	Easy	C#	✔️
1066	Campus Bikes II	Medium	C#, Java, JS	✔️
1067	Digit Count in Range	Hard		➖
1068	Product Sales Analysis I	Easy	MySQL, SQLServer	✔️
1069	Product Sales Analysis II	Easy	MySQL, SQLServer	✔️
1070	Product Sales Analysis III	Medium	MySQL, SQLServer	✔️
1071	Greatest Common Divisor of Strings	Easy	C#, JS	✔️
1072	Flip Columns For Maximum Number of Equal Rows	Medium	C#	✔️
1073	Adding Two Negabinary Numbers	Medium	C#	✔️
1074	Number of Submatrices That Sum to Target	Hard	C#, Java	✔️
1075	Project Employees I	Easy	MySQL, SQLServer	✔️
1076	Project Employees II	Easy	MySQL, SQLServer	✔️
1077	Project Employees III	Medium	MySQL, SQLServer	✔️
1078	Occurrences After Bigram	Easy	C#	✔️
1079	Letter Tile Possibilities	Medium	C#	✔️
1080	Insufficient Nodes in Root to Leaf Paths	Medium	C#	✔️
1081	Smallest Subsequence of Distinct Characters	Medium	C#, Java	✔️
1082	Sales Analysis I	Easy	MySQL, SQLServer	✔️
1083	Sales Analysis II	Easy	MySQL, SQLServer	✔️
1084	Sales Analysis III	Easy	MySQL, SQLServer	✔️
1085	Sum of Digits in the Minimum Number	Easy	C#	✔️
1086	High Five	Easy	C#	✔️
1087	Brace Expansion	Medium	C#	✔️
1088	Confusing Number II	Hard		➖
1089	Duplicate Zeros	Easy	C#, Java	✔️
1090	Largest Values From Labels	Medium	C#	✔️
1091	Shortest Path in Binary Matrix	Medium	C#, Java	✔️
1092	Shortest Common Supersequence	Hard		➖
1093	Statistics from a Large Sample	Medium	C#	✔️
1094	Car Pooling	Medium	C#, JS	✔️
1095	Find in Mountain Array	Hard	C#	✔️
1096	Brace Expansion II	Hard		➖
1097	Game Play Analysis V	Hard	MySQL, SQLServer	✔️
1098	Unpopular Books	Medium	MySQL, SQLServer	✔️
1099	Two Sum Less Than K	Easy	C#, JS	✔️
1100	Find K-Length Substrings With No Repeated Characters	Medium	C#	✔️
1101	The Earliest Moment When Everyone Become Friends	Medium	C#	✔️
1102	Path With Maximum Minimum Value	Medium	C#	✔️
1103	Distribute Candies to People	Easy	C#, Java	✔️
1104	Path In Zigzag Labelled Binary Tree	Medium	C#	✔️
1105	Filling Bookcase Shelves	Medium	C#	✔️
1106	Parsing A Boolean Expression	Hard		➖
1107	New Users Daily Count	Medium	MySQL, SQLServer	✔️
1108	Defanging an IP Address	Easy	C#	✔️
1109	Corporate Flight Bookings	Medium	C#, JS	✔️
1110	Delete Nodes And Return Forest	Medium	C#	✔️
1111	Maximum Nesting Depth of Two Valid Parentheses Strings	Medium	C#, Java	✔️
1112	Highest Grade For Each Student	Medium	MySQL, SQLServer	✔️
1113	Reported Posts	Easy	MySQL, SQLServer	✔️
1114	Print in Order	Easy	C#	✔️
1115	Print FooBar Alternately	Medium		➖
1116	Print Zero Even Odd	Medium		➖
1117	Building H2O	Medium		➖
1118	Number of Days in a Month	Easy	C#	✔️
1119	Remove Vowels from a String	Easy	C#	✔️
1120	Maximum Average Subtree	Medium	C#	✔️
1121	Divide Array Into Increasing Sequences	Hard		➖
1122	Relative Sort Array	Easy	C#, Java	✔️
1123	Lowest Common Ancestor of Deepest Leaves	Medium	C#	✔️
1124	Longest Well-Performing Interval	Medium	C#	✔️
1125	Smallest Sufficient Team	Hard	C#	✔️
1126	Active Businesses	Medium	SQLServer	✔️
1127	User Purchase Platform	Hard	MySQL, SQLServer	✔️
1128	Number of Equivalent Domino Pairs	Easy	C#	✔️
1129	Shortest Path with Alternating Colors	Medium	C#	✔️
1130	Minimum Cost Tree From Leaf Values	Medium	C#	✔️
1131	Maximum of Absolute Value Expression	Medium	C#, Java	✔️
1132	Reported Posts II	Medium	MySQL, SQLServer	✔️
1133	Largest Unique Number	Easy	C#, Java	✔️
1134	Armstrong Number	Easy	C#, Java	✔️
1135	Connecting Cities With Minimum Cost	Medium	C#, Java	✔️
1136	Parallel Courses	Medium	C#	✔️
1137	N-th Tribonacci Number	Easy	C#, Java, Python, JS	✔️
1138	Alphabet Board Path	Medium	C#, Java	✔️
1139	Largest 1-Bordered Square	Medium		➖
1140	Stone Game II	Medium	C#	✔️
1141	User Activity for the Past 30 Days I	Easy	MySQL, SQLServer	✔️
1142	User Activity for the Past 30 Days II	Easy	MySQL, SQLServer	✔️
1143	Longest Common Subsequence	Medium	C#, Java, Python, JS	✔️
1144	Decrease Elements To Make Array Zigzag	Medium	C#	✔️
1145	Binary Tree Coloring Game	Medium		➖
1146	Snapshot Array	Medium	C#	✔️
1147	Longest Chunked Palindrome Decomposition	Hard		➖
1148	Article Views I	Easy	MySQL, SQLServer	✔️
1149	Article Views II	Medium	MySQL, SQLServer	✔️
1150	Check If a Number Is Majority Element in a Sorted Array	Easy	C#	✔️
1151	Minimum Swaps to Group All 1's Together	Medium	C#	✔️
1152	Analyze User Website Visit Pattern	Medium	C#	✔️
1153	String Transforms Into Another String	Hard		➖
1154	Day of the Year	Easy	C#, JS	✔️
1155	Number of Dice Rolls With Target Sum	Medium	C#	✔️
1156	Swap For Longest Repeated Character Substring	Medium	C#	✔️
1157	Online Majority Element In Subarray	Hard		➖
1158	Market Analysis I	Medium	SQLServer	✔️
1159	Market Analysis II	Hard	MySQL, SQLServer	✔️
1160	Find Words That Can Be Formed by Characters	Easy	C#	✔️
1161	Maximum Level Sum of a Binary Tree	Medium	C#, Java	✔️
1162	As Far from Land as Possible	Medium	C#, Java, JS	✔️
1163	Last Substring in Lexicographical Order	Hard		➖
1164	Product Price at a Given Date	Medium	MySQL	✔️
1165	Single-Row Keyboard	Easy	C#, Java	✔️
1166	Design File System	Medium	C#	✔️
1167	Minimum Cost to Connect Sticks	Medium	C#, Java	✔️
1168	Optimize Water Distribution in a Village	Hard	C#	✔️
1169	Invalid Transactions	Medium	C#	✔️
1170	Compare Strings by Frequency of the Smallest Character	Medium	C#	✔️
1171	Remove Zero Sum Consecutive Nodes from Linked List	Medium	C#	✔️
1172	Dinner Plate Stacks	Hard		➖
1173	Immediate Food Delivery I	Easy	MySQL, SQLServer	✔️
1174	Immediate Food Delivery II	Medium	MySQL, SQLServer	✔️
1175	Prime Arrangements	Easy	C#, Java	✔️
1176	Diet Plan Performance	Easy	C#	✔️
1177	Can Make Palindrome from Substring	Medium	C#	✔️
1178	Number of Valid Words for Each Puzzle	Hard		➖
1179	Reformat Department Table	Easy	MySQL, SQLServer	✔️
1180	Count Substrings with Only One Distinct Letter	Easy	C#	✔️
1181	Before and After Puzzle	Medium	C#	✔️
1182	Shortest Distance to Target Color	Medium	C#, Java	✔️
1183	Maximum Number of Ones	Hard		➖
1184	Distance Between Bus Stops	Easy	C#	✔️
1185	Day of the Week	Easy	C#	✔️
1186	Maximum Subarray Sum with One Deletion	Medium		➖
1187	Make Array Strictly Increasing	Hard	C#	✔️
1188	Design Bounded Blocking Queue	Medium		➖
1189	Maximum Number of Balloons	Easy	C#, JS	✔️
1090	Reverse Substrings Between Each Pair of Parentheses	Medium	C#, Java	✔️
1191	K-Concatenation Maximum Sum	Medium	C#	✔️
1192	Critical Connections in a Network	Hard	C#	✔️
1193	Monthly Transactions I	Medium	MySQL, SQLServer	✔️
1194	Tournament Winners	Hard	MySQL, SQLServer	✔️
1195	Fizz Buzz Multithreaded	Medium		➖
1196	How Many Apples Can You Put into the Basket	Easy	C#	✔️
1197	Minimum Knight Moves	Medium	C#, Java	✔️
1198	Find Smallest Common Element in All Rows	Medium	C#, Java, JS	✔️
1199	Minimum Time to Build Blocks	Hard		➖
1200	Minimum Absolute Difference	Easy	C#, JS	✔️
1201	Ugly Number III	Medium	C#	✔️
1202	Smallest String With Swaps	Medium	C#	✔️
1203	Sort Items by Groups Respecting Dependencies	Hard		➖
1204	Last Person to Fit in the Bus	Medium	MySQL, SQLServer	✔️
1205	Monthly Transactions II	Medium	MySQL, SQLServer	✔️
1206	Design Skiplist	Hard		➖
1207	Unique Number of Occurrences	Easy	C#, JS	✔️
1208	Get Equal Substrings Within Budget	Medium	C#	✔️
1209	Remove All Adjacent Duplicates in String II	Medium	C#, Java	✔️
1210	Minimum Moves to Reach Target with Rotations	Hard		➖
1211	Queries Quality and Percentage	Easy	MySQL, SQLServer	✔️
1212	Team Scores in Football Tournament	Medium	SQLServer	✔️
1213	Intersection of Three Sorted Arrays	Easy	C#	✔️
1214	Two Sum BSTs	Medium	C#	✔️
1215	Stepping Numbers	Medium	C#	✔️
1216	Valid Palindrome III	Hard		➖
1217	Minimum Cost to Move Chips to The Same Position	Easy	C#, JS	✔️
1218	Longest Arithmetic Subsequence of Given Difference	Medium	C#	✔️
1219	Path with Maximum Gold	Medium	C#, JS	✔️
1220	Count Vowels Permutation	Hard	C#, Java	✔️
1221	Split a String in Balanced Strings	Easy	C#	✔️
1222	Queens That Can Attack the King	Medium	C#	✔️
1223	Dice Roll Simulation	Hard		➖
1224	Maximum Equal Frequency	Hard	C#	✔️
1225	Report Contiguous Dates	Hard	MySQL, SQLServer	✔️
1226	The Dining Philosophers	Medium		➖
1227	Airplane Seat Assignment Probability	Medium	C#, Java	✔️
1228	Missing Number In Arithmetic Progression	Easy	C#, Java	✔️
1229	Meeting Scheduler	Medium	C#, Java	✔️
1230	Toss Strange Coins	Medium		➖
1231	Divide Chocolate	Hard	C#	✔️
1232	Check If It Is a Straight Line	Easy	C#	✔️
1233	Remove Sub-Folders from the Filesystem	Medium	C#	✔️
1234	Replace the Substring for Balanced String	Medium	C#	✔️
1235	Maximum Profit in Job Scheduling	Hard	C#	✔️
1236	Web Crawler	Medium	C#	✔️
1237	Find Positive Integer Solution for a Given Equation	Medium	C#	✔️
1238	Circular Permutation in Binary Representation	Medium		➖
1239	Maximum Length of a Concatenated String with Unique Characters	Medium	C#, Java, JS	✔️
1240	Tiling a Rectangle with the Fewest Squares	Hard		➖
1241	Number of Comments per Post	Easy	MySQL, SQLServer	✔️
1242	Web Crawler Multithreaded	Medium		➖
1243	Array Transformation	Easy	C#	✔️
1244	Design A Leaderboard	Medium	C#	✔️
1245	Tree Diameter	Medium	C#	✔️
1246	Palindrome Removal	Hard	C#	✔️
1247	Minimum Swaps to Make Strings Equal	Medium	C#	✔️
1248	Count Number of Nice Subarrays	Medium	C#	✔️
1249	Minimum Remove to Make Valid Parentheses	Medium	C#, Java, JS	✔️
1250	Check If It Is a Good Array	Hard		➖
1251	Average Selling Price	Easy	MySQL, SQLServer	✔️
1252	Cells with Odd Values in a Matrix	Easy	C#	✔️
1253	Reconstruct a 2-Row Binary Matrix	Medium	C#	✔️
1254	Number of Closed Islands	Medium	C#, Java	✔️
1255	Maximum Score Words Formed by Letters	Hard	C#	✔️
1256	Encode Number	Medium	C#	✔️
1257	Smallest Common Region	Medium	C#	✔️
1258	Synonymous Sentences	Medium		➖
1259	Handshakes That Don't Cross	Hard		➖
1260	Shift 2D Grid	Easy	C#	✔️
1261	Find Elements in a Contaminated Binary Tree	Medium	C#, Java	✔️
1262	Greatest Sum Divisible by Three	Medium	C#	✔️
1263	Minimum Moves to Move a Box to Their Target Location	Hard		➖
1264	Page Recommendations	Medium	MySQL, SQLServer	✔️
1265	Print Immutable Linked List in Reverse	Medium	C#	✔️
1266	Minimum Time Visiting All Points	Easy	C#	✔️
1267	Count Servers that Communicate	Medium	C#, Java	✔️
1268	Search Suggestions System	Medium	C#, Java	✔️
1269	Number of Ways to Stay in the Same Place After Some Steps	Hard		➖
1270	All People Report to the Given Manager	Medium	MySQL, SQLServer	✔️
1271	Hexspeak	Easy	C#	✔️
1272	Remove Interval	Medium	C#, JS	✔️
1273	Delete Tree Nodes	Medium	C#	✔️
1274	Number of Ships in a Rectangle	Hard		➖
1275	Find Winner on a Tic Tac Toe Game	Easy	C#, Java	✔️
1276	Number of Burgers with No Waste of Ingredients	Medium	C#	✔️
1277	Count Square Submatrices with All Ones	Medium	C#	✔️
1278	Palindrome Partitioning III	Hard	C#	✔️
1279	Traffic Light Controlled Intersection	Easy	C#	✔️
1280	Students and Examinations	Easy	MySQL, SQLServer	✔️
1281	Subtract the Product and Sum of Digits of an Integer	Easy	C#	✔️
1282	Group the People Given the Group Size They Belong To	Medium	C#, Java, JS	✔️
1283	Find the Smallest Divisor Given a Threshold	Medium	C#	✔️
1284	Minimum Number of Flips to Convert Binary Matrix to Zero Matrix	Hard	C#	✔️
1285	Find the Start and End Number of Continuous Ranges	Medium	MySQL, SQLServer	✔️
1286	Iterator for Combination	Medium	C#, Java	✔️
1287	Element Appearing More Than 25% In Sorted Array	Easy	C#	✔️
1288	Remove Covered Intervals	Medium	C#, JS	✔️
1289	Minimum Falling Path Sum II	Hard		➖
1290	Convert Binary Number in a Linked List to Integer	Easy	C#, JS	✔️
1291	Sequential Digits	Medium	C#	✔️
1292	Maximum Side Length of a Square with Sum Less than or Equal to Threshold	Medium	C#	✔️
1293	Shortest Path in a Grid with Obstacles Elimination	Hard	C#	✔️
1294	Weather Type in Each Country	Easy	MySQL, SQLServer	✔️
1295	Find Numbers with Even Number of Digits	Easy	C#	✔️
1296	Divide Array in Sets of K Consecutive Numbers	Medium	C#, Java	✔️
1297	Maximum Number of Occurrences of a Substring	Medium	C#	✔️
1298	Maximum Candies You Can Get from Boxes	Hard	C#	✔️
1299	Replace Elements with Greatest Element on Right Side	Easy	C#	✔️
1300	Sum of Mutated Array Closest to Target	Medium	C#	✔️
1301	Number of Paths with Max Score	Hard		➖
1302	Deepest Leaves Sum	Medium	C#, Java, JS	✔️
1303	Find the Team Size	Easy	MySQL, SQLServer	✔️
1304	Find N Unique Integers Sum up to Zero	Easy	C#, Java	✔️
1305	All Elements in Two Binary Search Trees	Medium	C#, Java, JS	✔️
1306	Jump Game III	Medium	C#, Java, JS	✔️
1307	Verbal Arithmetic Puzzle	Hard		➖
1308	Running Total for Different Genders	Medium	MySQL, SQLServer	✔️
1309	Decrypt String from Alphabet to Integer Mapping	Easy	C#	✔️
1310	XOR Queries of a Subarray	Medium	C#, Java, JS	✔️
1311	Get Watched Videos by Your Friends	Medium	C#	✔️
1312	Minimum Insertion Steps to Make a String Palindrome	Hard	C#	✔️
1313	Decompress Run-Length Encoded List	Easy	C#, Java	✔️
1314	Matrix Block Sum	Medium	C#	✔️
1315	Sum of Nodes with Even-Valued Grandparent	Medium	C#, Java	✔️
1316	Distinct Echo Substrings	Hard		➖
1317	Convert Integer to the Sum of Two No-Zero Integers	Easy	C#	✔️
1318	Minimum Flips to Make a OR b Equal to c	Medium	C#	✔️
1319	Number of Operations to Make Network Connected	Medium	C#, Java, JS	✔️
1320	Minimum Distance to Type a Word Using Two Fingers	Hard		➖
1321	Restaurant Growth	Medium	MySQL, SQLServer	✔️
1322	Ads Performance	Easy	MySQL, SQLServer	✔️
1323	Maximum 69 Number	Easy	C#, Java, JS	✔️
1324	Print Words Vertically	Medium	C#	✔️
1325	Delete Leaves With a Given Value	Medium	C#, Java	✔️
1326	Minimum Number of Taps to Open to Water a Garden	Hard		➖
1327	List the Products Ordered in a Period	Easy	MySQL, SQLServer	✔️
1328	Break a Palindrome	Medium	C#, Java, JS	✔️
1329	Sort the Matrix Diagonally	Medium	C#, Java	✔️
1330	Reverse Subarray To Maximize Array Value	Hard		➖
1331	Rank Transform of an Array	Easy	C#	✔️
1332	Remove Palindromic Subsequences	Easy	C#, Java, JS	✔️
1333	Filter Restaurants by Vegan-Friendly, Price and Distance	Medium	C#	✔️
1334	Find the City With the Smallest Number of Neighbors at a Threshold Distance	Medium	C#	✔️
1335	Minimum Difficulty of a Job Schedule	Hard	C#	✔️
1336	Number of Transactions per Visit	Hard	MySQL, SQLServer	✔️
1337	The K Weakest Rows in a Matrix	Easy	C#, Java	✔️
1338	Reduce Array Size to The Half	Medium	C#, JS	✔️
1339	Maximum Product of Splitted Binary Tree	Medium	C#, JS	✔️
1340	Jump Game V	Hard		➖
1341	Movie Rating	Medium	MySQL, SQLServer	✔️
1342	Number of Steps to Reduce a Number to Zero	Easy	C#, [Java](