LeetCode

LeetCode solutions in C++ 11 and and Java and Python3.

NO.	Title	solution	Difficulty	Tag
1	Two Sum	Cpp Java Python3	Easy	Mapping
2	Add Two Numbers	Cpp Java Python3	Medium	LinkedList
3	Median of Two Sorted Arrays		Hard
4	Longest Palindromic Substring	Cpp	Medium
5	ZigZag Conversion		Medium
6	Reverse Integer		Easy
7	String to Integer (atoi)		Medium
8	Palindrome Number		Easy
9	Regular Expression Matching		Hard
10	Container With Most Water		Medium
11	Integer to Roman		Medium
12	Roman to Integer		Easy
13	Longest Common Prefix		Easy
14	3Sum		Medium
15	3Sum Closest		Medium
16	Letter Combinations of a Phone Number		Medium
17	4Sum		Medium
18	Remove Nth Node From End of List		Medium
19	Valid Parentheses		Easy
20	Merge Two Sorted Lists		Easy
21	Generate Parentheses		Medium
22	Merge k Sorted Lists		Hard
23	Swap Nodes in Pairs		Medium
24	Reverse Nodes in k-Group		Hard
25	Remove Duplicates from Sorted Array		Easy
26	Remove Element		Easy
27	Implement strStr()		Easy
28	Divide Two Integers		Medium
29	Substring with Concatenation of All Words		Hard
30	Next Permutation		Medium
31	Longest Valid Parentheses		Hard
32	Search in Rotated Sorted Array		Medium
33	Search for a Range		Medium
34	Search Insert Position		Easy
35	Valid Sudoku		Medium
36	Sudoku Solver		Hard
37	Count and Say		Easy
38	Combination Sum		Medium
39	Combination Sum II		Medium
40	First Missing Positive		Hard
41	Trapping Rain Water		Hard
42	Multiply Strings		Medium
43	Wildcard Matching		Hard
44	Jump Game II		Hard
45	Permutations		Medium
46	Permutations II		Medium
47	Rotate Image		Medium
48	Group Anagrams		Medium
49	Pow(x, n)		Medium
50	N-Queens		Hard
51	N-Queens II		Hard
52	Maximum Subarray		Easy
53	Spiral Matrix		Medium
54	Jump Game		Medium
55	Merge Intervals		Medium
56	Insert Interval		Hard
57	Length of Last Word		Easy
58	Spiral Matrix II		Medium
59	Permutation Sequence		Medium
60	Rotate List		Medium
61	Unique Paths		Medium
62	Unique Paths II		Medium
63	Minimum Path Sum		Medium
64	Valid Number		Hard
65	Plus One		Easy
66	Add Binary		Easy
67	Text Justification		Hard
68	Sqrt(x)		Easy
69	Climbing Stairs		Easy
70	Simplify Path		Medium
71	Edit Distance		Hard
72	Set Matrix Zeroes		Medium
73	Search a 2D Matrix		Medium
74	Sort Colors		Medium
75	Minimum Window Substring		Hard
76	Combinations		Medium
77	Subsets		Medium
78	Word Search		Medium
79	Remove Duplicates from Sorted Array II		Medium
80	Search in Rotated Sorted Array II		Medium
81	Remove Duplicates from Sorted List II		Medium
82	Remove Duplicates from Sorted List		Easy
83	Largest Rectangle in Histogram		Hard
84	Maximal Rectangle		Hard
85	Partition List		Medium
86	Scramble String		Hard
87	Merge Sorted Array		Easy
88	Gray Code		Medium
89	Subsets II		Medium
90	Decode Ways		Medium
91	Reverse Linked List II		Medium
92	Restore IP Addresses		Medium
93	Binary Tree Inorder Traversal		Medium
94	Unique Binary Search Trees II		Medium
95	Unique Binary Search Trees		Medium
96	Interleaving String		Hard
97	Validate Binary Search Tree		Medium
98	Recover Binary Search Tree		Hard
99	Same Tree		Easy
100	Symmetric Tree		Easy
101	Binary Tree Level Order Traversal		Medium
102	Binary Tree Zigzag Level Order Traversal		Medium
103	Maximum Depth of Binary Tree		Easy
104	Construct Binary Tree from Preorder and Inorder Traversal		Medium
105	Construct Binary Tree from Inorder and Postorder Traversal		Medium
106	Binary Tree Level Order Traversal II		Easy
107	Convert Sorted Array to Binary Search Tree		Easy
108	Convert Sorted List to Binary Search Tree		Medium
109	Balanced Binary Tree		Easy
110	Minimum Depth of Binary Tree		Easy
111	Path Sum		Easy
112	Path Sum II		Medium
113	Flatten Binary Tree to Linked List		Medium
114	Distinct Subsequences		Hard
115	Populating Next Right Pointers in Each Node		Medium
116	Populating Next Right Pointers in Each Node II		Medium
117	Pascal's Triangle		Easy
118	Pascal's Triangle II		Easy
119	Triangle		Medium
120	Best Time to Buy and Sell Stock		Easy
121	Best Time to Buy and Sell Stock II		Easy
122	Best Time to Buy and Sell Stock III		Hard
123	Binary Tree Maximum Path Sum		Hard
124	Valid Palindrome		Easy
125	Word Ladder II		Hard
126	Word Ladder		Medium
127	Longest Consecutive Sequence		Hard
128	Sum Root to Leaf Numbers		Medium
129	Surrounded Regions		Medium
130	Palindrome Partitioning		Medium
131	Palindrome Partitioning II		Hard
132	Clone Graph		Medium
133	Gas Station		Medium
134	Candy		Hard
135	Single Number		Easy
136	Single Number II		Medium
137	Copy List with Random Pointer		Medium
138	Word Break		Medium
139	Word Break II		Hard
140	Linked List Cycle		Easy
141	Linked List Cycle II		Medium
142	Reorder List		Medium
143	Binary Tree Preorder Traversal		Medium
144	Binary Tree Postorder Traversal		Hard
145	LRU Cache		Hard
146	Insertion Sort List		Medium
147	Sort List		Medium
148	Max Points on a Line		Hard
149	Evaluate Reverse Polish Notation		Medium
150	Reverse Words in a String		Medium
151	Maximum Product Subarray		Medium
152	Find Minimum in Rotated Sorted Array		Medium
153	Find Minimum in Rotated Sorted Array II		Hard
154	Min Stack		Easy
155	Binary Tree Upside Down		None
156	Read N Characters Given Read4		None
157	Read N Characters Given Read4 II - Call multiple times		None
158	Longest Substring with At Most Two Distinct Characters		None
159	Intersection of Two Linked Lists		Easy
160	One Edit Distance		None
161	Find Peak Element		Medium
162	Missing Ranges		None
163	Maximum Gap		Hard
164	Compare Version Numbers		Medium
165	Fraction to Recurring Decimal		Medium
166	Two Sum II - Input array is sorted		Easy
167	Excel Sheet Column Title		Easy
168	Majority Element		Easy
169	Two Sum III - Data structure design		None
170	Excel Sheet Column Number		Easy
171	Factorial Trailing Zeroes		Easy
172	Binary Search Tree Iterator		Medium
173	Dungeon Game		Hard
174	Combine Two Tables		Easy
175	Second Highest Salary		Easy
176	Nth Highest Salary		Medium
177	Rank Scores		Medium
178	Largest Number		Medium
179	Consecutive Numbers		Medium
180	Employees Earning More Than Their Managers		Easy
181	Duplicate Emails		Easy
182	Customers Who Never Order		Easy
183	Department Highest Salary		Medium
184	Department Top Three Salaries		Hard
185	Reverse Words in a String II		None
186	Repeated DNA Sequences		Medium
187	Best Time to Buy and Sell Stock IV		Hard
188	Rotate Array		Easy
189	Reverse Bits		Easy
190	Number of 1 Bits		Easy
191	Word Frequency		Medium
192	Valid Phone Numbers		Easy
193	Transpose File		Medium
194	Tenth Line		Easy
195	Delete Duplicate Emails		Easy
196	Rising Temperature		Easy
197	House Robber		Easy
198	Binary Tree Right Side View		Medium
199	Number of Islands		Medium
200	Bitwise AND of Numbers Range		Medium
201	Happy Number		Easy
202	Remove Linked List Elements		Easy
203	Count Primes		Easy
204	Isomorphic Strings		Easy
205	Reverse Linked List		Easy
206	Course Schedule		Medium
207	Implement Trie (Prefix Tree)		Medium
208	Minimum Size Subarray Sum		Medium
209	Course Schedule II		Medium
210	Add and Search Word - Data structure design		Medium
211	Word Search II		Hard
212	House Robber II		Medium
213	Shortest Palindrome		Hard
214	Kth Largest Element in an Array		Medium
215	Combination Sum III		Medium
216	Contains Duplicate		Easy
217	The Skyline Problem		Hard
218	Contains Duplicate II		Easy
219	Contains Duplicate III		Medium
220	Maximal Square		Medium
221	Count Complete Tree Nodes		Medium
222	Rectangle Area		Medium
223	Basic Calculator		Hard
224	Implement Stack using Queues		Easy
225	Invert Binary Tree		Easy
226	Basic Calculator II		Medium
227	Summary Ranges		Medium
228	Majority Element II		Medium
229	Kth Smallest Element in a BST		Medium
230	Power of Two		Easy
231	Implement Queue using Stacks		Easy
232	Number of Digit One		Hard
233	Palindrome Linked List		Easy
234	Lowest Common Ancestor of a Binary Search Tree		Easy
235	Lowest Common Ancestor of a Binary Tree		Medium
236	Delete Node in a Linked List		Easy
237	Product of Array Except Self		Medium
238	Sliding Window Maximum		Hard
239	Search a 2D Matrix II		Medium
240	Different Ways to Add Parentheses		Medium
241	Valid Anagram		Easy
242	Shortest Word Distance		None
243	Shortest Word Distance II		None
244	Shortest Word Distance III		None
245	Strobogrammatic Number		None
246	Strobogrammatic Number II		None
247	Strobogrammatic Number III		None
248	Group Shifted Strings		None
249	Count Univalue Subtrees		None
250	Flatten 2D Vector		None
251	Meeting Rooms		None
252	Meeting Rooms II		None
253	Factor Combinations		None
254	Verify Preorder Sequence in Binary Search Tree		None
255	Paint House		None
256	Binary Tree Paths		Easy
257	Add Digits		Easy
258	3Sum Smaller		None
259	Single Number III		Medium
260	Graph Valid Tree		None
261	Trips and Users		Hard
262	Ugly Number		Easy
263	Ugly Number II		Medium
264	Paint House II		None
265	Palindrome Permutation		None
266	Palindrome Permutation II		None
267	Missing Number		Easy
268	Alien Dictionary		None
269	Closest Binary Search Tree Value		None
270	Encode and Decode Strings		None
271	Closest Binary Search Tree Value II		None
272	Integer to English Words		Hard
273	H-Index		Medium
274	H-Index II		Medium
275	Paint Fence		None
276	Find the Celebrity		None
277	First Bad Version		Easy
278	Perfect Squares		Medium
279	Wiggle Sort		None
280	Zigzag Iterator		None
281	Expression Add Operators		Hard
282	Move Zeroes		Easy
283	Peeking Iterator		Medium
284	Inorder Successor in BST		None
285	Walls and Gates		None
286	Find the Duplicate Number		Medium
287	Unique Word Abbreviation		None
288	Game of Life		Medium
289	Word Pattern		Easy
290	Word Pattern II		None
291	Nim Game		Easy
292	Flip Game		None
293	Flip Game II		None
294	Find Median from Data Stream		Hard
295	Best Meeting Point		None
296	Serialize and Deserialize Binary Tree		Hard
297	Binary Tree Longest Consecutive Sequence		None
298	Bulls and Cows		Medium
299	Longest Increasing Subsequence		Medium
300	Remove Invalid Parentheses		Hard
301	Smallest Rectangle Enclosing Black Pixels		None
302	Range Sum Query - Immutable		Easy
303	Range Sum Query 2D - Immutable		Medium
304	Number of Islands II		None
305	Additive Number		Medium
306	Range Sum Query - Mutable		Medium
307	Range Sum Query 2D - Mutable		None
308	Best Time to Buy and Sell Stock with Cooldown		Medium
309	Minimum Height Trees		Medium
310	Sparse Matrix Multiplication		None
311	Burst Balloons		Hard
312	Super Ugly Number		Medium
313	Binary Tree Vertical Order Traversal		None
314	Count of Smaller Numbers After Self		Hard
315	Remove Duplicate Letters		Hard
316	Shortest Distance from All Buildings		None
317	Maximum Product of Word Lengths		Medium
318	Bulb Switcher		Medium
319	Generalized Abbreviation		None
320	Create Maximum Number		Hard
321	Coin Change		Medium
322	Number of Connected Components in an Undirected Graph		None
323	Wiggle Sort II		Medium
324	Maximum Size Subarray Sum Equals k		None
325	Power of Three		Easy
326	Count of Range Sum		Hard
327	Odd Even Linked List		Medium
328	Longest Increasing Path in a Matrix		Hard
329	Patching Array		Hard
330	Verify Preorder Serialization of a Binary Tree		Medium
331	Reconstruct Itinerary		Medium
332	Largest BST Subtree		None
333	Increasing Triplet Subsequence		Medium
334	Self Crossing		Hard
335	Palindrome Pairs		Hard
336	House Robber III		Medium
337	Counting Bits		Medium
338	Nested List Weight Sum		None
339	Longest Substring with At Most K Distinct Characters		None
340	Flatten Nested List Iterator		Medium
341	Power of Four		Easy
342	Integer Break		Medium
343	Reverse String		Easy
344	Reverse Vowels of a String		Easy
345	Moving Average from Data Stream		None
346	Top K Frequent Elements		Medium
347	Design Tic-Tac-Toe		None
348	Intersection of Two Arrays		Easy
349	Intersection of Two Arrays II		Easy
350	Android Unlock Patterns		None
351	Data Stream as Disjoint Intervals		Hard
352	Design Snake Game		None
353	Russian Doll Envelopes		Hard
354	Design Twitter		Medium
355	Line Reflection		None
356	Count Numbers with Unique Digits		Medium
357	Rearrange String k Distance Apart		None
358	Logger Rate Limiter		None
359	Sort Transformed Array		None
360	Bomb Enemy		None
361	Design Hit Counter		None
362	Max Sum of Rectangle No Larger Than K		Hard
363	Nested List Weight Sum II		None
364	Water and Jug Problem		Medium
365	Find Leaves of Binary Tree		None
366	Valid Perfect Square		Easy
367	Largest Divisible Subset		Medium
368	Plus One Linked List		None
369	Range Addition		None
370	Sum of Two Integers		Easy
371	Super Pow		Medium
372	Find K Pairs with Smallest Sums		Medium
373	Guess Number Higher or Lower		Easy
374	Guess Number Higher or Lower II		Medium
375	Wiggle Subsequence		Medium
376	Combination Sum IV		Medium
377	Kth Smallest Element in a Sorted Matrix		Medium
378	Design Phone Directory		None
379	Insert Delete GetRandom O(1)		Medium
380	Insert Delete GetRandom O(1) - Duplicates allowed		Hard
381	Linked List Random Node		Medium
382	Ransom Note		Easy
383	Shuffle an Array		Medium
384	Mini Parser		Medium
385	Lexicographical Numbers		Medium
386	First Unique Character in a String		Easy
387	Longest Absolute File Path		Medium
388	Find the Difference		Easy
389	Elimination Game		Medium
390	Perfect Rectangle		Hard
391	Is Subsequence		Medium
392	UTF-8 Validation		Medium
393	Decode String		Medium
394	Longest Substring with At Least K Repeating Characters		Medium
395	Rotate Function		Medium
396	Integer Replacement		Medium
397	Random Pick Index		Medium
398	Evaluate Division		Medium
399	Nth Digit		Easy
400	Binary Watch		Easy
401	Remove K Digits		Medium
402	Frog Jump		Hard
403	Sum of Left Leaves		Easy
404	Convert a Number to Hexadecimal		Easy
405	Queue Reconstruction by Height		Medium
406	Trapping Rain Water II		Hard
407	Valid Word Abbreviation		None
408	Longest Palindrome		Easy
409	Split Array Largest Sum		Hard
410	Minimum Unique Word Abbreviation		None
411	Fizz Buzz		Easy
412	Arithmetic Slices		Medium
413	Third Maximum Number		Easy
414	Add Strings		Easy
415	Partition Equal Subset Sum		Medium
416	Pacific Atlantic Water Flow		Medium
417	Sentence Screen Fitting		None
418	Battleships in a Board		Medium
419	Strong Password Checker		Hard
420	Maximum XOR of Two Numbers in an Array		Medium
421	Valid Word Square		None
422	Reconstruct Original Digits from English		Medium
423	Longest Repeating Character Replacement		Medium
424	Word Squares		None
425	All O'one Data Structure		Hard
426	Minimum Genetic Mutation		Medium
427	Number of Segments in a String		Easy
428	Non-overlapping Intervals		Medium
429	Find Right Interval		Medium
430	Path Sum III		Easy
431	Find All Anagrams in a String		Easy
432	Ternary Expression Parser		None
433	K-th Smallest in Lexicographical Order		Hard
434	Arranging Coins		Easy
435	Find All Duplicates in an Array		Medium
436	String Compression		Easy
437	Sequence Reconstruction		None
438	Add Two Numbers II		Medium
439	Arithmetic Slices II - Subsequence		Hard
440	Number of Boomerangs		Easy
441	Find All Numbers Disappeared in an Array		Easy
442	Serialize and Deserialize BST		Medium
443	Delete Node in a BST		Medium
444	Sort Characters By Frequency		Medium
445	Minimum Number of Arrows to Burst Balloons		Medium
446	Minimum Moves to Equal Array Elements		Easy
447	4Sum II		Medium
448	Assign Cookies		Easy
449	132 Pattern		Medium
450	Circular Array Loop		Medium
451	Poor Pigs		Easy
452	Repeated Substring Pattern		Easy
453	LFU Cache		Hard
454	Hamming Distance		Easy
455	Minimum Moves to Equal Array Elements II		Medium
456	Island Perimeter		Easy
457	Can I Win		Medium
458	Optimal Account Balancing		None
459	Count The Repetitions		Hard
460	Unique Substrings in Wraparound String		Medium
461	Validate IP Address		Medium
462	Convex Polygon		None
463	Encode String with Shortest Length		None
464	Concatenated Words		Hard
465	Matchsticks to Square		Medium
466	Ones and Zeroes		Medium
467	Heaters		Easy
468	Number Complement		Easy
469	Total Hamming Distance		Medium
470	Largest Palindrome Product		Easy
471	Sliding Window Median		Hard
472	Magical String		Medium
473	License Key Formatting		Easy
474	Smallest Good Base		Hard
475	Find Permutation		None
476	Max Consecutive Ones		Easy
477	Predict the Winner		Medium
478	Max Consecutive Ones II		None
479	Zuma Game		Hard
480	The Maze		None
481	Increasing Subsequences		Medium
482	Construct the Rectangle		Easy
483	Reverse Pairs		Hard
484	Target Sum		Medium
485	Teemo Attacking		Medium
486	Next Greater Element I		Easy
487	Diagonal Traverse		Medium
488	The Maze III		None
489	Keyboard Row		Easy
490	Find Mode in Binary Search Tree		Easy
491	IPO		Hard
492	Next Greater Element II		Medium
493	Base 7		Easy
494	The Maze II		None
495	Relative Ranks		Easy
496	Perfect Number		Easy
497	Most Frequent Subtree Sum		Medium
498	Find Bottom Left Tree Value		Medium
499	Freedom Trail		Hard
500	Find Largest Value in Each Tree Row		Medium
501	Longest Palindromic Subsequence		Medium
502	Super Washing Machines		Hard
503	Coin Change 2		Medium
504	Detect Capital		Easy
505	Longest Uncommon Subsequence I		Easy
506	Longest Uncommon Subsequence II		Medium
507	Continuous Subarray Sum		Medium
508	Longest Word in Dictionary through Deleting		Medium
509	Contiguous Array		Medium
510	Beautiful Arrangement		Medium
511	Word Abbreviation		None
512	Minesweeper		Medium
513	Minimum Absolute Difference in BST		Easy
514	Lonely Pixel I		None
515	K-diff Pairs in an Array		Easy
516	Lonely Pixel II		None
517	Design TinyURL		Medium
518	Encode and Decode TinyURL		Medium
519	Construct Binary Tree from String		None
520	Complex Number Multiplication		Medium
521	Convert BST to Greater Tree		Easy
522	Minimum Time Difference		Medium
523	Single Element in a Sorted Array		Medium
524	Reverse String II		Easy
525	01 Matrix		Medium
526	Diameter of Binary Tree		Easy
527	Output Contest Matches		None
528	Boundary of Binary Tree		None
529	Remove Boxes		Hard
530	Friend Circles		Medium
531	Split Array with Equal Sum		None
532	Binary Tree Longest Consecutive Sequence II		None
533	Student Attendance Record I		Easy
534	Student Attendance Record II		Hard
535	Optimal Division		Medium
536	Brick Wall		Medium
537	Split Concatenated Strings		None
538	Next Greater Element III		Medium
539	Reverse Words in a String III		Easy
540	Subarray Sum Equals K		Medium
541	Array Partition I		Easy
542	Longest Line of Consecutive One in Matrix		None
543	Binary Tree Tilt		Easy
544	Find the Closest Palindrome		Hard
545	Array Nesting		Medium
546	Reshape the Matrix		Easy
547	Permutation in String		Medium
548	Maximum Vacation Days		None
549	Median Employee Salary		None
550	Managers with at Least 5 Direct Reports		None
551	Find Median Given Frequency of Numbers		None
552	Subtree of Another Tree		Easy
553	Squirrel Simulation		None
554	Winning Candidate		None
555	Distribute Candies		Easy
556	Out of Boundary Paths		Medium
557	Employee Bonus		None
558	Get Highest Answer Rate Question		None
559	Find Cumulative Salary of an Employee		None
560	Count Student Number in Departments		None
561	Shortest Unsorted Continuous Subarray		Easy
562	Kill Process		None
563	Delete Operation for Two Strings		Medium
564	Find Customer Referee		None
565	Investments in 2016		None
566	Customer Placing the Largest Number of Orders		None
567	Erect the Fence		Hard
568	Design In-Memory File System		None
569	Tag Validator		Hard
570	Fraction Addition and Subtraction		Medium
571	Valid Square		Medium
572	Longest Harmonious Subsequence		Easy
573	Big Countries		Easy
574	Classes More Than 5 Students		Easy
575	Friend Requests I: Overall Acceptance Rate		None
576	Range Addition II		Easy
577	Minimum Index Sum of Two Lists		Easy
578	Non-negative Integers without Consecutive Ones		Hard
579	Human Traffic of Stadium		Hard
580	Friend Requests II: Who Has the Most Friends		None
581	Consecutive Available Seats		None
582	Design Compressed String Iterator		None
583	Can Place Flowers		Easy
584	Construct String from Binary Tree		Easy
585	Sales Person		None
586	Tree Node		None
587	Find Duplicate File in System		Medium
588	Triangle Judgement		None
589	Valid Triangle Number		Medium
590	Shortest Distance in a Plane		None
591	Shortest Distance in a Line		None
592	Second Degree Follower		None
593	Average Salary: Departments VS Company		None
594	Add Bold Tag in String		None
595	Merge Two Binary Trees		Easy
596	Students Report By Geography		None
597	Biggest Single Number		None
598	Not Boring Movies		Easy
599	Task Scheduler		Medium
600	Add One Row to Tree		Medium
601	Maximum Distance in Arrays		None
602	Minimum Factorization		None
603	Exchange Seats		Medium
604	Swap Salary		Easy
605	Maximum Product of Three Numbers		Easy
606	K Inverse Pairs Array		Hard
607	Course Schedule III		Hard
608	Design Excel Sum Formula		None
609	Smallest Range		Hard
610	Sum of Square Numbers		Easy
611	Find the Derangement of An Array		None
612	Design Log Storage System		None
613	Exclusive Time of Functions		Medium
614	Average of Levels in Binary Tree		Easy
615	Shopping Offers		Medium
616	Decode Ways II		Hard
617	Solve the Equation		Medium
618	Design Search Autocomplete System		None
619	Maximum Average Subarray I		Easy
620	Maximum Average Subarray II		None
621	Set Mismatch		Easy
622	Maximum Length of Pair Chain		Medium
623	Palindromic Substrings		Medium
624	Replace Words		Medium
625	Dota2 Senate		Medium
626	2 Keys Keyboard		Medium
627	4 Keys Keyboard		None
628	Find Duplicate Subtrees		Medium
629	Two Sum IV - Input is a BST		Easy
630	Maximum Binary Tree		Medium
631	Print Binary Tree		Medium
632	Coin Path		None
633	Judge Route Circle		Easy
634	Find K Closest Elements		Medium
635	Split Array into Consecutive Subsequences		Medium
636	Remove 9		None
637	Image Smoother		Easy
638	Maximum Width of Binary Tree		Medium
639	Equal Tree Partition		None
640	Strange Printer		Hard
641	Non-decreasing Array		Easy
642	Path Sum IV		None
643	Beautiful Arrangement II		Medium
644	Kth Smallest Number in Multiplication Table		Hard
645	Trim a Binary Search Tree		Easy
646	Maximum Swap		Medium
647	Second Minimum Node In a Binary Tree		Easy
648	Bulb Switcher II		Medium
649	Number of Longest Increasing Subsequence		Medium
650	Longest Continuous Increasing Subsequence		Easy
651	Cut Off Trees for Golf Event		Hard
652	Implement Magic Dictionary		Medium
653	Map Sum Pairs		Medium
654	Valid Parenthesis String		Medium
655	24 Game		Hard
656	Valid Palindrome II		Easy
657	Next Closest Time		None
658	Baseball Game		Easy
659	K Empty Slots		None
660	Redundant Connection		Medium
661	Redundant Connection II		Hard
662	Repeated String Match		Easy
663	Longest Univalue Path		Easy
664	Knight Probability in Chessboard		Medium
665	Maximum Sum of 3 Non-Overlapping Subarrays		Hard
666	Employee Importance		Easy
667	Stickers to Spell Word		Hard
668	Top K Frequent Words		Medium
669	Binary Number with Alternating Bits		Easy
670	Number of Distinct Islands		None
671	Max Area of Island		Easy
672	Count Binary Substrings		Easy
673	Degree of an Array		Easy
674	Partition to K Equal Sum Subsets		Medium
675	Falling Squares		Hard
676	Number of Distinct Islands II		None
677	Minimum ASCII Delete Sum for Two Strings		Medium
678	Subarray Product Less Than K		Medium
679	Best Time to Buy and Sell Stock with Transaction Fee		Medium
680	Range Module		Hard
681	Max Stack		None
682	1-bit and 2-bit Characters		Easy
683	Maximum Length of Repeated Subarray		Medium
684	Find K-th Smallest Pair Distance		Hard
685	Longest Word in Dictionary		Easy
686	Accounts Merge		Medium
687	Remove Comments		Medium
688	Candy Crush		None
689	Find Pivot Index		Easy
690	Split Linked List in Parts		Medium
691	Number of Atoms		Hard
692	Minimum Window Subsequence		None
693	Self Dividing Numbers		Easy
694	My Calendar I		Medium
695	Count Different Palindromic Subsequences		Hard
696	My Calendar II		Medium
697	My Calendar III		Hard
698	Flood Fill		Easy
699	Sentence Similarity		Easy
700	Asteroid Collision		Medium
701	Parse Lisp Expression		Hard
702	Sentence Similarity II		Medium
703	Monotone Increasing Digits		Medium
704	Daily Temperatures		Medium
705	Delete and Earn		Medium
706	Cherry Pickup		Hard
707	Closest Leaf in a Binary Tree		New
708	Network Delay Time		New
709	Find Smallest Letter Greater Than Target		New
710	Prefix and Suffix Search		New