LeetCode All In One

English | 简体中文

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Provide all my solutions and explanations in Chinese for all the Leetcode coding problems.

Same as this: LeetCode All in One 题目讲解汇总(持续更新中...)

Note: All explanations are written in Github Issues, please do not create any new issue or pull request in this project since the problem index should be consistent with the issue index, thanks!

('$' means the problem is locked on Leetcode, '*' means the problem is related to Database, '#' means the problem is related to Shell.)

#	Title	Solution	Difficulty
919	Complete Binary Tree Inserter	55.70%	Medium
918	Maximum Sum Circular Subarray	33.20%	Medium
917	Reverse Only Letters	56.30%	Easy
916	Word Subsets	45.90%	Medium
915	Partition Array into Disjoint Intervals	43.90%	Medium
914	X of a Kind in a Deck of Cards	34.00%	Easy
913	Cat and Mouse	29.90%	Hard
912	Sort an Array	62.90%	Medium
911	Online Election	48.30%	Medium
910	Smallest Range II	24.90%	Medium
909	Snakes and Ladders	36.10%	Easy
908	Smallest Range I	65.00%	Easy
907	Sum of Subarray Minimums	29.40%	Medium
906	Super Palindromes	30.80%	Hard
905	Sort Array By Parity	72.60%	Easy
904	Fruit Into Baskets	41.70%	Medium
903	Valid Permutations for DI Sequence	45.10%	Hard
902	Numbers At Most N Given Digit Set	28.80%	Hard
901	Online Stock Span	49.90%	Medium
900	RLE Iterator	50.50%	Medium
899	Orderly Queue	47.70%	Hard
898	Bitwise ORs of Subarrays	34.70%	Medium
897	Increasing Order Search Tree	65.20%	Easy
896	Monotonic Array	55.40%	Easy
895	Maximum Frequency Stack	56.70%	Hard
894	All Possible Full Binary Trees	71.30%	Medium
893	Groups of Special-Equivalent Strings	63.00%	Easy
892	Surface Area of 3D Shapes	56.10%	Easy
891	Sum of Subsequence Widths	29.20%	Hard
890	Find and Replace Pattern	71.30%	Medium
889	Construct Binary Tree from Preorder and Postorder Traversal	60.70%	Medium
888	Fair Candy Swap	56.90%	Easy
887	Super Egg Drop	24.90%	Hard
886	Possible Bipartition	40.90%	Medium
885	Spiral Matrix III	64.80%	Medium
884	Uncommon Words from Two Sentences	60.90%	Easy
883	Projection Area of 3D Shapes	65.90%	Easy
882	Reachable Nodes In Subdivided Graph	38.20%	Hard
881	Boats to Save People	44.10%	Medium
880	Decoded String at Index	23.00%	Medium
879	Profitable Schemes	36.20%	Hard
878	Nth Magical Number	25.40%	Hard
877	Stone Game	61.10%	Medium
876	Middle of the Linked List	63.80%	Easy
875	Koko Eating Bananas	45.90%	Medium
874	Walking Robot Simulation	31.70%	Easy
873	Length of Longest Fibonacci Subsequence	46.00%	Medium
872	Leaf-Similar Trees	63.10%	Easy
871	Minimum Number of Refueling Stops	28.70%	Hard
870	Advantage Shuffle	42.20%	Medium
869	Reordered Power of 2	50.60%	Medium
868	Binary Gap	59.30%	Easy
867	Transpose Matrix	63.90%	Easy
866	Prime Palindrome	20.00%	Medium
865	Smallest Subtree with all the Deepest Nodes	55.40%	Medium
864	Shortest Path to Get All Keys	35.70%	Hard
863	All Nodes Distance K in Binary Tree	46.80%	Medium
862	Shortest Subarray with Sum at Least K	22.00%	Hard
861	Score After Flipping Matrix	69.30%	Medium
860	Lemonade Change	50.20%	Easy
859	Buddy Strings	27.60%	Easy
858	Mirror Reflection	52.00%	Medium
857	Minimum Cost to Hire K Workers	47.30%	Hard
856	Score of Parentheses	55.90%	Medium
855	Exam Room	38.10%	Medium
854	K-Similar Strings	33.20%	Hard
853	Car Fleet	39.30%	Medium
852	Peak Index in a Mountain Array	68.50%	Easy
851	Loud and Rich	47.40%	Medium
850	Rectangle Area II	44.00%	Hard
849	Maximize Distance to Closest Person	40.40%	Easy
848	Shifting Letters	39.90%	Medium
847	Shortest Path Visiting All Nodes	45.90%	Hard
846	Hand of Straights	48.60%	Medium
845	Longest Mountain in Array	34.00%	Medium
844	Backspace String Compare	45.50%	Easy
843	Guess the Word	42.60%	Hard
842	Split Array into Fibonacci Sequence	34.60%	Medium
841	Keys and Rooms	59.70%	Medium
840	Magic Squares In Grid	35.10%	Easy
839	Similar String Groups	33.50%	Hard
838	Push Dominoes	42.80%	Medium
837	New 21 Game	29.50%	Medium
836	Rectangle Overlap	45.50%	Easy
835	Image Overlap	50.30%	Medium
834	Sum of Distances in Tree	38.10%	Hard
833	Find And Replace in String	44.50%	Medium
832	Flipping an Image	71.30%	Easy
831	Masking Personal Information	41.50%	Medium
830	Positions of Large Groups	47.40%	Easy
829	Consecutive Numbers Sum	32.10%	Hard
828	Unique Letter String	38.10%	Hard
827	Making A Large Island	42.10%	Hard
826	Most Profit Assigning Work	34.70%	Medium
825	Friends Of Appropriate Ages	35.00%	Medium
824	Goat Latin	56.70%	Easy
823	Binary Trees With Factors	31.50%	Medium
822	Card Flipping Game	39.70%	Medium
821	Shortest Distance to a Character	62.60%	Easy
820	Short Encoding of Words	46.00%	Medium
819	Most Common Word	41.50%	Easy
818	Race Car	34.00%	Hard
817	Linked List Components	51.90%	Medium
816	Ambiguous Coordinates	42.40%	Medium
815	Bus Routes	36.10%	Hard
814	Binary Tree Pruning	68.30%	Medium
813	Largest Sum of Averages	42.40%	Medium
812	Largest Triangle Area	53.80%	Easy
811	Subdomain Visit Count	61.50%	Easy
810	Chalkboard XOR Game	41.90%	Hard
809	Expressive Words	39.50%	Medium
808	Soup Servings	33.60%	Medium
807	Max Increase to Keep City Skyline	79.60%	Medium
806	Number of Lines To Write String	62.10%	Easy
805	Split Array With Same Average	21.00%	Hard
804	Unique Morse Code Words	71.30%	Easy
803	Bricks Falling When Hit	22.90%	Hard
802	Find Eventual Safe States	39.20%	Medium
801	Minimum Swaps To Make Sequences Increasing	31.00%	Medium
800	Similar RGB Color $	54.50%	Easy
799	Champagne Tower	29.90%	Medium
798	Smallest Rotation with Highest Score	34.30%	Hard
797	All Paths From Source to Target	67.40%	Medium
796	Rotate String	49.60%	Easy
795	Number of Subarrays with Bounded Maximum	41.60%	Medium
794	Valid Tic-Tac-Toe State	27.80%	Medium
793	Preimage Size of Factorial Zeroes Function	40.80%	Hard
792	Number of Matching Subsequences	37.30%	Medium
791	Custom Sort String	59.40%	Medium
790	Domino and Tromino Tiling	32.80%	Medium
789	Escape The Ghosts	51.00%	Medium
788	Rotated Digits	51.00%	Easy
787	Cheapest Flights Within K Stops	29.90%	Medium
786	K-th Smallest Prime Fraction	32.50%	Hard
785	Is Graph Bipartite	38.50%	Medium
784	Letter Case Permutation	53.00%	Easy
783	Minimum Distance Between BST Nodes	47.80%	Easy
782	Transform to Chessboard	37.50%	Hard
781	Rabbits in Forest	49.80%	Medium
780	Reaching Points	23.90%	Hard
779	K-th Symbol in Grammar	37.30%	Medium
778	Swim in Rising Water	44.60%	Hard
777	Swap Adjacent in LR String	28.90%	Medium
776	Split BST $	49.90%	Medium
775	Global and Local Inversions	33.60%	Medium
774	Minimize Max Distance to Gas Station $	32.80%	Hard
773	Sliding Puzzle	46.50%	Hard
772	Basic Calculator III $	40.10%	Hard
771	Jewels and Stones	81.90%	Easy
770	Basic Calculator IV	42.10%	Hard
769	Max Chunks To Make Sorted	48.00%	Medium
768	Max Chunks To Make Sorted II	43.20%	Hard
767	Reorganize String	36.50%	Medium
766	Toeplitz Matrix	57.90%	Easy
765	Couples Holding Hands	48.50%	Hard
764	Largest Plus Sign	39.20%	Medium
763	Partition Labels	64.10%	Medium
762	Prime Number of Set Bits in Binary Representation	55.00%	Easy
761	Special Binary String	41.00%	Hard
760	Find Anagram Mappings $	75.60%	Easy
759	Employee Free Time $	51.90%	Hard
758	Bold Words in String $	37.90%	Easy
757	Set Intersection Size At Least Two	34.60%	Hard
756	Pyramid Transition Matrix	45.50%	Medium
755	Pour Water $	34.00%	Medium
754	Reach a Number	26.10%	Medium
753	Cracking the Safe	39.70%	Hard
752	Open the Lock	38.20%	Medium
751	IP to CIDR $	54.80%	Easy
750	Number Of Corner Rectangles $	51.00%	Medium
749	Contain Virus	39.60%	Hard
748	Shortest Completing Word	53.50%	Medium
747	Largest Number At Least Twice of Others	42.60%	Easy
746	Min Cost Climbing Stairs	43.60%	Easy
745	Prefix and Suffix Search	24.50%	Hard
744	Find Smallest Letter Greater Than Target	45.30%	Easy
743	Network Delay Time	34.30%	Medium
742	Closest Leaf in a Binary Tree $	33.20%	Medium
741	Cherry Pickup	22.50%	Hard
740	Delete and Earn	42.60%	Medium
739	Daily Temperatures	53.50%	Medium
738	Monotone Increasing Digits	41.80%	Medium
737	Sentence Similarity II $	41.20%	Medium
736	Parse Lisp Expression	42.00%	Hard
735	Asteroid Collision	37.60%	Medium
734	Sentence Similarity $	38.60%	Easy
733	Flood Fill	49.30%	Easy
732	My Calendar III	51.30%	Hard
731	My Calendar II	35.00%	Medium
730	Count Different Palindromic Subsequences	32.40%	Hard
729	My Calendar I	40.10%	Medium
728	Self Dividing Numbers	68.50%	Easy
727	Minimum Window Subsequence	30.10%	Hard
726	Number of Atoms	45.00%	Hard
725	Split Linked List in Parts	50.00%	Medium
724	Find Pivot Index	41.00%	Easy
723	Candy Crush $	56.10%	Medium
722	Remove Comments	26.30%	Medium
721	Accounts Merge	29.60%	Medium
720	Longest Word in Dictionary	40.60%	Easy
719	Find K-th Smallest Pair Distance	26.10%	Hard
718	Maximum Length of Repeated Subarray	39.90%	Medium
717	1-bit and 2-bit Characters	50.90%	Easy
716	Max Stack $	35.50%	Hard
715	Range Module	31.00%	Hard
714	Best Time to Buy and Sell Stock with Transaction Fee	41.60%	Medium
713	Subarray Product Less Than K	32.90%	Medium
712	Minimum ASCII Delete Sum for Two Strings	50.90%	Medium
711	Number of Distinct Islands II $	39.40%	Hard
710	Random Pick with Blacklist	29.80%	Hard
709	To Lower Case	74.50%	Easy
708	Insert into a Cyclic Sorted List $	25.50%	Medium
707	Design Linked List	19.10%	Easy
706	Design HashMap	49.10%	Easy
705	Design HashSet	43.60%	Easy
704	Binary Search	40.10%	Easy
703	Kth Largest Element in a Stream	39.60%	Easy
702	Search in a Sorted Array of Unknown Size	43.00%	Medium
701	Insert into a Binary Search Tree	67.90%	Medium
700	Search in a Binary Search Tree	62.70%	Easy
699	Falling Squares	36.80%	Hard
698	Partition to K Equal Sum Subsets	35.60%	Medium
697	Degree of an Array	47.90%	Easy
696	Count Binary Substrings	51.90%	Easy
695	Max Area of Island	53.30%	Easy
694	Number of Distinct Islands $	43.90%	Medium
693	Binary Number with Alternating Bits	54.20%	Easy
692	Top K Frequent Words	41.70%	Medium
691	Stickers to Spell Word	32.30%	Hard
690	Employee Importance	53.60%	Easy
689	Maximum Sum of 3 Non-Overlapping Subarrays	41.70%	Hard
688	Knight Probability in Chessboard	38.90%	Medium
687	Longest Univalue Path	32.90%	Easy
686	Repeated String Match	31.70%	Easy
685	Redundant Connection II	28.40%	Hard
684	Redundant Connection	37.40%	Medium
683	K Empty Slots	37.00%	Hard
682	Baseball Game	58.60%	Easy
681	Next Closest Time $	43.00%	Medium
680	Valid Palindrome II	31.10%	Easy
679	24 Game	38.30%	Hard
678	Valid Parenthesis String	28.30%	Medium
677	Map Sum Pairs	53.80%	Medium
676	Implement Magic Dictionary	50.70%	Medium
675	Cut Off Trees for Golf Event	27.20%	Hard
674	Longest Continuous Increasing Subsequence	43.20%	Easy
673	Number of Longest Increasing Subsequence	30.80%	Medium
672	Bulb Switcher II	47.60%	Medium
671	Second Minimum Node In a Binary Tree	42.30%	Easy
670	Maximum Swap	38.40%	Medium
669	Trim a Binary Search Tree	58.70%	Easy
668	Kth Smallest Number in Multiplication Table	36.30%	Hard
667	Beautiful Arrangement II	51.50%	Medium
666	Path Sum IV $	48.90%	Medium
665	Non-decreasing Array	21.20%	Easy
664	Strange Printer	31.10%	Hard
663	Equal Tree Partition $	36.70%	Medium
662	Maximum Width of Binary Tree	37.00%	Medium
661	Image Smoother	46.60%	Easy
660	Remove 9 $	46.10%	Hard
659	Split Array into Consecutive Subsequences	39.40%	Medium
658	Find K Closest Elements	36.30%	Medium
657	Judge Route Circle	69.30%	Easy
656	Coin Path $	24.60%	Hard
655	Print Binary Tree	50.80%	Medium
654	Maximum Binary Tree	70.80%	Medium
653	Two Sum IV - Input is a BST	50.60%	Easy
652	Find Duplicate Subtrees	33.20%	Medium
651	4 Keys Keyboard $	46.70%	Medium
650	2 Keys Keyboard	42.70%	Medium
649	Dota2 Senate	35.60%	Medium
648	Replace Words	48.40%	Medium
647	Palindromic Substrings	55.70%	Medium
646	Maximum Length of Pair Chain	47.40%	Medium
645	Set Mismatch	40.40%	Easy
644	Maximum Average Subarray II $	20.30%	Hard
643	Maximum Average Subarray I	38.40%	Easy
642	Design Search Autocomplete System $	29.40%	Hard
641	Design Circular Deque	48.00%	Medium
640	Solve the Equation	39.00%	Medium
639	Decode Ways II	22.80%	Hard
638	Shopping Offers	41.50%	Medium
637	Average of Levels in Binary Tree	55.60%	Easy
636	Exclusive Time of Functions	40.30%	Medium
635	Design Log Storage System $	47.70%	Medium
634	Find the Derangement of An Array $	32.70%	Medium
633	Sum of Square Numbers	31.60%	Easy
632	Smallest Range	42.80%	Hard
631	Design Excel Sum Formula $	25.60%	Hard
630	Course Schedule III	20.50%	Medium
629	K Inverse Pairs Array	23.90%	Hard
628	Maximum Product of Three Numbers	45.40%	Easy
627	Swap Salary	67.40%	Easy
626	Exchange Seats	49.60%	Medium
625	Minimum Factorization	29.50%	Medium
624	Maximum Distance in Arrays $	32.70%	Easy
623	Add One Row to Tree	48.70%	Medium
622	Design Circular Queue	36.60%	Medium
621	Task Scheduler	41.40%	Medium
620	Not Boring Movies	59.80%	Easy
619	Biggest Single Number $	36.60%	Easy
618	Students Report By Geography $	40.40%	Hard
617	Merge Two Binary Trees	69.60%	Easy
616	Add Bold Tag in String $	37.30%	Medium
615	Average Salary: Departments VS Company $	33.00%	Hard
614	Second Degree Follower $	22.70%	Medium
613	Shortest Distance in a Line $	70.60%	Easy
612	Shortest Distance in a Plane $	51.00%	Medium
611	Valid Triangle Number	38.90%	Medium
610	Triangle Judgement $	59.10%	Easy
609	Find Duplicate File in System	52.50%	Medium
608	Tree Node $	54.60%	Medium
607	Sales Person $	51.10%	Easy
606	Construct String from Binary Tree	51.80%	Easy
605	Can Place Flowers	30.00%	Easy
604	Design Compressed String Iterator $	31.60%	Easy
603	Consecutive Available Seats $	54.50%	Easy
602	Friend Requests II: Who Has the Most Friends $	42.50%	Medium
601	Human Traffic of Stadium	33.80%	Hard
600	Non-negative Integers without Consecutive Ones	27.40%	Hard
599	Minimum Index Sum of Two Lists	48.00%	Easy
598	Range Addition II	48.30%	Easy
597	Friend Requests I: Overall Acceptance Rate $	38.40%	Easy
596	Classes More Than 5 Students	33.40%	Easy
595	Big Countries	72.00%	Easy
594	Longest Harmonious Subsequence	40.00%	Easy
593	Valid Square	39.20%	Medium
592	Fraction Addition and Subtraction	47.00%	Medium
591	Tag Validator	26.40%	Hard
590	N-ary Tree Postorder Traversal	63.00%	Easy
589	N-ary Tree Preorder Traversal	63.10%	Easy
588	Design In-Memory File System $	32.40%	Hard
587	Erect the Fence	29.90%	Hard
586	Customer Placing the Largest Number of Orders $	62.50%	Easy
585	Investments in 2016 $	44.60%	Medium
584	Find Customer Referee $	63.60%	Easy
583	Delete Operation for Two Strings	44.00%	Medium
582	Kill Process $	47.70%	Medium
581	Shortest Unsorted Continuous Subarray	30.10%	Easy
580	Count Student Number in Departments $	40.00%	Medium
579	Find Cumulative Salary of an Employee $	30.90%	Hard
578	Get Highest Answer Rate Question $	33.10%	Medium
577	Employee Bonus $	53.80%	Easy
576	Out of Boundary Paths	33.10%	Medium
575	Distribute Candies	59.50%	Easy
574	Winning Candidate $	34.50%	Medium
573	Squirrel Simulation $	51.00%	Medium
572	Subtree of Another Tree	41.00%	Easy
571	Find Median Given Frequency of Numbers $	44.90%	Hard
570	Managers with at Least 5 Direct Reports $	59.00%	Medium
569	Median Employee Salary $	41.60%	Hard
568	Maximum Vacation Days $	39.90%	Hard
567	Permutation in String	36.30%	Medium
566	Reshape the Matrix	59.80%	Easy
565	Array Nesting	50.00%	Medium
564	Find the Closest Palindrome	16.60%	Hard
563	Binary Tree Tilt	47.00%	Easy
562	Longest Line of Consecutive One in Matrix $	38.80%	Medium
561	Array Partition I	69.80%	Easy
560	Subarray Sum Equals K	41.80%	Medium
559	Maximum Depth of N-ary Tree	62.10%	Easy
558	Quad Tree Intersection	36.40%	Easy
557	Reverse Words in a String III	61.20%	Easy
556	Next Greater Element III	27.70%	Medium
555	Split Concatenated Strings $	30.00%	Medium
554	Brick Wall	42.70%	Medium
553	Optimal Division	55.20%	Medium
552	Student Attendance Record II	28.50%	Hard
551	Student Attendance Record I	43.90%	Easy
549	Binary Tree Longest Consecutive Sequence II $	38.10%	Medium
548	Split Array with Equal Sum $	30.80%	Medium
547	Friend Circles	49.00%	Medium
546	Remove Boxes	29.60%	Hard
545	Boundary of Binary Tree $	29.10%	Medium
544	Output Contest Matches $	73.20%	Medium
543	Diameter of Binary Tree	42.70%	Easy
542	01 Matrix	32.50%	Medium
541	Reverse String II	44.40%	Easy
540	Single Element in a Sorted Array	55.90%	Medium
539	Minimum Time Difference	44.70%	Medium
538	Convert BST to Greater Tree	52.70%	Medium
537	Complex Number Multiplication	65.90%	Medium
536	Construct Binary Tree from String $	36.30%	Medium
535	Encode and Decode TinyURL	76.10%	Medium
534	Design TinyURL	N/A	Medium
533	Lonely Pixel II $	38.90%	Medium
532	K-diff Pairs in an Array	27.20%	Easy
531	Lonely Pixel I $	50.20%	Medium
530	Minimum Absolute Difference in BST	48.00%	Easy
529	Minesweeper	52.00%	Medium
528	Random Pick with Weight	41.80%	Medium
527	Word Abbreviation $	33.90%	Hard
526	Beautiful Arrangement	53.50%	Medium
525	Contiguous Array	34.40%	Medium
524	Longest Word in Dictionary through Deleting	40.20%	Medium
523	Continuous Subarray Sum	21.3	Medium
522	Longest Uncommon Subsequence II	28.10%	Medium
521	Longest Uncommon Subsequence I	50.70%	Easy
520	Detect Capital	54.20%	Easy
519	Random Flip Matrix	32.20%	Medium
518	Coin Change 2	33.20%	Medium
517	Super Washing Machines	34.60%	Hard
516	Longest Palindromic Subsequence	42.00%	Medium
515	Find Largest Value in Each Tree Row	52.70%	Medium
514	Freedom Trail	27.20%	Hard
513	Find Bottom Left Tree Value	55.60%	Medium
510	Inorder Successor in BST II $	56.20%	Medium
509	Fibonacci Number	66.40%	Easy
508	Most Frequent Subtree Sum	52.00%	Medium
507	Perfect Number	32.70%	Easy
506	Relative Ranks	48.50%	Easy
505	The Maze II	34.80%	Medium
504	Base 7	46.40%	Easy
503	Next Greater Element II	46.20%	Medium
502	IPO	32.40%	Hard
501	Find Mode in Binary Search Tree	39.40%	Easy
500	Keyboard Row	60.20%	Easy
499	The Maze III	32.00%	Hard
498	Diagonal Traverse	46.20%	Medium
497	Random Point in Non-overlapping Rectangles	33.20%	Medium
496	Next Greater Element I	58.80%	Easy
495	Teemo Attacking	51.90%	Medium
494	Target Sum	44.40%	Medium
493	Reverse Pairs	17.10%	Hard
492	Construct the Rectangle	49.70%	Easy
491	Increasing Subsequences	39.30%	Medium
490	The Maze	42.80%	Medium
489	Robot Room Cleaner	57.10%	Hard
488	Zuma Game	38.00%	Hard
487	Max Consecutive Ones II $	42.70%	Medium
486	Predict the Winner	43.60%	Medium
485	Max Consecutive Ones	55.30%	Easy
484	Find Permutation $	50.50%	Medium
483	Smallest Good Base	30.60%	Hard
482	License Key Formatting	41.20%	Medium
481	Magical String	46.20%	Medium
480	Sliding Window Median	31.00%	Hard
479	Largest Palindrome Product	23.90%	Easy
478	Generate Random Point in a Circle	33.80%	Medium
477	Total Hamming Distance	44.10%	Medium
476	Number Complement	61.20%	Easy
475	Heaters	30.20%	Easy
474	Ones and Zeroes	34.90%	Medium
473	Matchsticks to Square	31.80%	Medium
472	Concatenated Words	29.20%	Hard
471	Encode String with Shortest Length $	43.50%	Hard
470	Implement Rand10() Using Rand7()	43.00%	Medium
469	Convex Polygon $	27.20%	Medium
468	Validate IP Address	22.10%	Medium
467	Unique Substrings in Wraparound String	29.90%	Medium
466	Count The Repetitions	24.20%	Hard
465	Optimal Account Balancing $	29.20%	Hard
464	Can I Win	22.20%	Medium
463	Island Perimeter	56.70%	Easy
462	Minimum Moves to Equal Array Elements II	50.90%	Medium
461	Hamming Distance	73.20%	Easy
460	LFU Cache	18.30%	Hard
459	Repeated Substring Pattern	39.70%	Easy
458	Poor Pigs	40.70%	Easy
457	Circular Array Loop	20.60%	Medium
456	132 Pattern	28.00%	Medium
455	Assign Cookies	48.10%	Easy
454	4Sum II	42.80%	Medium
453	Minimum Moves to Equal Array Elements	46.30%	Easy
452	Minimum Number of Arrows to Burst Balloons	42.10%	Medium
451	Sort Characters By Frequency	50.90%	Medium
450	Delete Node in a BST	34.50%	Medium
449	Serialize and Deserialize BST	41.20%	Medium
448	Find All Numbers Disappeared in an Array	58.30%	Easy
447	Number of Boomerangs	42.20%	Easy
446	Arithmetic Slices II - Subsequence	22.30%	Hard
445	Add Two Numbers II	45.40%	Medium
444	Sequence Reconstruction $	20.50%	Medium
443	String Compression	35.80%	Easy
442	Find All Duplicates in an Array	46.40%	Medium
441	Arranging Coins	36.20%	Easy
440	K-th Smallest in Lexicographical Order	21.50%	Hard
439	Ternary Expression Parser $	49.40%	Medium
438	Find All Anagrams in a String	33.50%	Easy
437	Path Sum III	38.60%	Easy
436	Find Right Interval	42.30%	Medium
435	Non-overlapping Intervals	39.80%	Medium
434	Number of Segments in a String	38.40%	Easy
433	Minimum Genetic Mutation	33.50%	Medium
432	All O`one Data Structure	28.30%	Hard
431	Encode N-ary Tree to Binary Tree $	53.70%	Hard
430	Flatten a Multilevel Doubly Linked List	36.20%	Medium
429	N-ary Tree Level Order Traversal	55.80%	Easy
428	Serialize and Deserialize N-ary Tree $	48.10%	Hard
427	Construct Quad Tree	49.20%	Easy
426	Convert Binary Search Tree to Sorted Doubly Linked List	43.30%	Medium
425	Word Squares $	40.10%	Hard
424	Longest Repeating Character Replacement	38.10%	Medium
423	Reconstruct Original Digits from English	40.80%	Medium
422	Valid Word Square $	36.40%	Easy
421	Maximum XOR of Two Numbers in an Array	36.40%	Medium
420	Strong Password Checker	22.10%	Hard
419	Battleships in a Board	59.30%	Medium
418	Sentence Screen Fitting $	25.10%	Medium
417	Pacific Atlantic Water Flow	31.10%	Medium
416	Partition Equal Subset Sum	36.80%	Medium
415	Add Strings	41.50%	Easy
414	Third Maximum Number	26.50%	Easy
413	Arithmetic Slices	53.50%	Medium
412	Fizz Buzz	57.50%	Easy
411	Minimum Unique Word Abbreviation $	25.60%	Hard
410	Split Array Largest Sum	25.00%	Hard
409	Longest Palindrome	44.90%	Easy
408	Valid Word Abbreviation $	26.20%	Easy
407	Trapping Rain Water II	33.10%	Hard
406	Queue Reconstruction by Height	54.10%	Medium
405	Convert a Number to Hexadecimal	41.80%	Easy
404	Sum of Left Leaves	46.20%	Easy
403	Frog Jump	31.70%	Hard
402	Remove K Digits	25.90%	Medium
401	Binary Watch	43.00%	Easy
400	Nth Digit	30.70%	Easy
399	Evaluate Division	34.60%	Medium
398	Random Pick Index	30.40%	Medium
397	Integer Replacement	25.90%	Easy
396	Rotate Function	28.40%	Easy
395	Longest Substring with At Least K Repeating Characters	32.50%	Medium
394	Decode String	38.60%	Medium
393	UTF-8 Validation	33.00%	Medium
392	Is Subsequence	44.10%	Medium
391	Perfect Rectangle	13.30%	Hard
390	Elimination Game	12.50%	Medium
389	Find the Difference	49.90%	Easy
388	Longest Absolute File Path	28.30%	Medium
387	First Unique Character in a String	43.10%	Easy
386	Lexicographical Numbers	31.00%	Medium
385	Mini Parser	26.90%	Medium
384	Shuffle an Array	45.50%	Medium
383	Ransom Note	44.60%	Easy
382	Linked List Random Node	48.60%	Medium
381	Insert Delete GetRandom O(1) - Duplicates allowed	30.90%	Hard
380	Insert Delete GetRandom O(1)	33.80%	Medium
379	Design Phone Directory $	25.80%	Medium
378	Kth Smallest Element in a Sorted Matrix	40.20%	Medium
377	Combination Sum IV	37.50%	Medium
376	Wiggle Subsequence	35.80%	Medium
375	Guess Number Higher or Lower II	28.30%	Medium
374	Guess Number Higher or Lower	31.70%	Easy
373	Find K Pairs with Smallest Sums	25.50%	Medium
372	Super Pow	30.10%	Medium
371	Sum of Two Integers	54.00%	Easy
370	Range Addition $	49.90%	Medium
369	Plus One Linked List $	50.10%	Medium
368	Largest Divisible Subset	32.00%	Medium
367	Valid Perfect Square	36.60%	Medium
366	Find Leaves of Binary Tree $	53.60%	Medium
365	Water and Jug Problem	20.10%	Medium
364	Nested List Weight Sum II $	47.20%	Medium
363	Max Sum of Rectangle No Larger Than K	27.00%	Hard
362	Design Hit Counter $	48.30%	Medium
361	Bomb Enemy $	32.60%	Medium
360	Sort Transformed Array $	40.80%	Medium
359	Logger Rate Limiter $	56.00%	Easy
358	Rearrange String k Distance Apart $	26.90%	Hard
357	Count Numbers with Unique Digits	42.50%	Medium
356	Line Reflection $	28.70%	Medium
355	Design Twitter	22.20%	Medium
354	Russian Doll Envelopes	27.10%	Hard
353	Design Snake Game $	19.80%	Medium
352	Data Stream as Disjoint Intervals	34.40%	Hard
351	Android Unlock Patterns $	32.00%	Medium
350	Intersection of Two Arrays II	41.50%	Easy
349	Intersection of Two Arrays	47.80%	Easy
348	Design Tic-Tac-Toe $	45.60%	Medium
347	Top K Frequent Elements	44.50%	Medium
346	Moving Average from Data Stream $	69.20%	Easy
345	Reverse Vowels of a String	35.30%	Easy
344	Reverse String	58.90%	Easy
343	Integer Break	43.60%	Medium
342	Power of Four	34.10%	Easy
341	Flatten Nested List Iterator $	18.70%	Medium
340	Longest Substring with At Most K Distinct Characters $	36.30%	Hard
339	Nested List Weight Sum $	54.60%	Easy
338	Counting Bits	55.40%	Medium
337	House Robber III	37.00%	Medium
336	Palindrome Pairs	18.70%	Hard
335	Self Crossing	18.00%	Medium
334	Increasing Triplet Subsequence	33.20%	Medium
333	Largest BST Subtree $	26.50%	Medium
332	Reconstruct Itinerary	23.40%	Medium
331	Verify Preorder Serialization of a Binary Tree	31.50%	Medium
330	Patching Array	28.80%	Medium
329	Longest Increasing Path in a Matrix	29.50%	Medium
328	Odd Even Linked List	37.80%	Easy
327	Count of Range Sum	24.30%	Hard
326	Power of Three	35.30%	Easy
325	Maximum Size Subarray Sum Equals k $	39.60%	Easy
324	Wiggle Sort II	20.10%	Medium
323	Number of Connected Components in an Undirected Graph $	43.30%	Medium
322	Coin Change	24.90%	Medium
321	Create Maximum Number	19.10%	Hard
320	Generalized Abbreviation $	40.40%	Medium
319	Bulb Switcher	39.20%	Medium
318	Maximum Product of Word Lengths	38.70%	Medium
317	Shortest Distance from All Buildings $	29.10%	Hard
316	Remove Duplicate Letters	23.00%	Medium
315	Count of Smaller Numbers After Self	28.20%	Hard
314	Binary Tree Vertical Order Traversal $	30.10%	Medium
313	Super Ugly Number	31.20%	Medium
312	Burst Balloons	24.50%	Medium
311	Sparse Matrix Multiplication $	40.00%	Medium
310	Minimum Height Trees	20.20%	Medium
309	Best Time to Buy and Sell Stock with Cooldown	32.60%	Medium
308	Range Sum Query 2D - Mutable $	20.30%	Hard
307	Range Sum Query - Mutable	14.50%	Medium
306	Additive Number	23.30%	Medium
305	Number of Islands II $	26.70%	Hard
304	Range Sum Query 2D - Immutable	21.50%	Medium
303	Range Sum Query - Immutable	25.70%	Easy
302	Smallest Rectangle Enclosing Black Pixels $	36.70%	Hard
301	Remove Invalid Parentheses	27.00%	Hard
300	Longest Increasing Subsequence	31.50%	Medium
299	Bulls and Cows	23.80%	Easy
298	Binary Tree Longest Consecutive Sequence $	32.20%	Medium
297	Serialize and Deserialize Binary Tree	23.80%	Medium
296	Best Meeting Point $	41.40%	Hard
295	Find Median from Data Stream	18.60%	Hard
294	Flip Game II $	38.10%	Medium
293	Flip Game $	47.60%	Easy
292	Nim Game	49.50%	Easy
291	Word Pattern II $	31.50%	Hard
290	Word Pattern	26.50%	Easy
289	Game of Life	32.60%	Medium
288	Unique Word Abbreviation $	16.80%	Easy
287	Find the Duplicate Number	32.80%	Hard
286	Walls and Gates $	29.90%	Medium
285	Inorder Successor in BST $	32.50%	Medium
284	Peeking Iterator	31.00%	Medium
283	Move Zeroes	41.40%	Easy
282	Expression Add Operators	18.90%	Hard
281	Zigzag Iterator $	37.20%	Medium
280	Wiggle Sort $	43.30%	Medium
279	Perfect Squares	28.80%	Medium
278	First Bad Version	19.80%	Easy
277	Find the Celebrity $	31.70%	Medium
276	Paint Fence $	25.00%	Easy
275	H-Index II	31.40%	Medium
274	H-Index	25.30%	Medium
273	Integer to English Words	15.50%	Medium
272	Closest Binary Search Tree Value II $	26.90%	Hard
271	Encode and Decode Strings $	25.40%	Medium
270	Closest Binary Search Tree Value $	29.40%	Easy
269	Alien Dictionary $	16.50%	Hard
268	Missing Number	34.70%	Medium
267	Palindrome Permutation II $	22.50%	Medium
266	Palindrome Permutation $	45.80%	Easy
265	Paint House II $	30.00%	Hard
264	Ugly Number II	21.60%	Medium
263	Ugly Number	32.60%	Easy
262	Trips and Users *	16.10%	Hard
261	Graph Valid Tree $	25.40%	Medium
260	Single Number III	37.60%	Medium
259	3Sum Smaller $	34.20%	Medium
258	Add Digits	46.50%	Easy
257	Binary Tree Paths	21.90%	Easy
256	Paint House $	38.40%	Medium
255	Verify Preorder Sequence in Binary Search Tree $	32.30%	Medium
254	Factor Combinations $	29.00%	Medium
253	Meeting Rooms II $	28.80%	Medium
252	Meeting Rooms $	35.40%	Easy
251	Flatten 2D Vector $	28.30%	Medium
250	Count Univalue Subtrees $	32.70%	Medium
249	Group Shifted Strings $	25.20%	Easy
248	Strobogrammatic Number III $	21.80%	Hard
247	Strobogrammatic Number II $	26.70%	Medium
246	Strobogrammatic Number $	31.60%	Easy
245	Shortest Word Distance III $	43.20%	Medium
244	Shortest Word Distance II $	33.70%	Medium
243	Shortest Word Distance $	41.80%	Easy
242	Valid Anagram	39.30%	Easy
241	Different Ways to Add Parentheses	27.10%	Medium
240	Search a 2D Matrix II	31.40%	Medium
239	Sliding Window Maximum	24.30%	Hard
238	Product of Array Except Self	42.40%	Medium
237	Delete Node in a Linked List	50.90%	Easy
236	Lowest Common Ancestor of a Binary Tree	28.30%	Medium
235	Lowest Common Ancestor of a Binary Search Tree	38.90%	Medium
234	Palindrome Linked List	23.80%	Easy
233	Number of Digit One	16.10%	Medium
232	Implement Queue using Stacks	37.40%	Easy
231	Power of Two	31.30%	Easy
230	Kth Smallest Element in a BST	30.50%	Medium
229	Majority Element II	30.50%	Medium
228	Summary Ranges	21.10%	Easy
227	Basic Calculator II	18.00%	Medium
226	Invert Binary Tree	35.40%	Easy
225	Implement Stack using Queues	29.60%	Medium
224	Basic Calculator	15.80%	Medium
223	Rectangle Area	25.60%	Easy
222	Count Complete Tree Nodes	19.40%	Medium
221	Maximal Square	20.30%	Medium
220	Contains Duplicate III	15.30%	Medium
219	Contains Duplicate II	25.60%	Easy
218	The Skyline Problem	16.20%	Hard
217	Contains Duplicate	35.90%	Easy
216	Combination Sum III	27.70%	Medium
215	Kth Largest Element in an Array	27.30%	Medium
214	Shortest Palindrome	16.80%	Hard
213	House Robber II	26.30%	Medium
212	Word Search II	15.00%	Hard
211	Add and Search Word - Data structure design	20.70%	Medium
210	Course Schedule II	19.30%	Medium
209	Minimum Size Subarray Sum	22.90%	Medium
208	Implement Trie (Prefix Tree)	24.80%	Medium
207	Course Schedule	21.70%	Medium
206	Reverse Linked List	31.50%	Easy
205	Isomorphic Strings	24.20%	Easy
204	Count Primes	19.00%	Easy
203	Remove Linked List Elements	25.80%	Easy
202	Happy Number	31.40%	Easy
201	Bitwise AND of Numbers Range	23.30%	Medium
200	Number of Islands	21.90%	Medium
199	Binary Tree Right Side View	27.10%	Medium
198	House Robber	28.80%	Easy
197	Rising Temperature *	25.90%	Easy
196	Delete Duplicate Emails *	19.00%	Easy
195	Tenth Line #	32.20%	Easy
194	Transpose File #	21.40%	Medium
193	Valid Phone Numbers #	24.40%	Easy
192	Word Frequency #	26.10%	Medium
191	Number of 1 Bits	37.30%	Easy
190	Reverse Bits	28.40%	Easy
189	Rotate Array	17.80%	Easy
188	Best Time to Buy and Sell Stock IV	17.30%	Hard
187	Repeated DNA Sequences	19.50%	Medium
186	Reverse Words in a String II $	31.10%	Medium
185	Department Top Three Salaries *	15.20%	Hard
184	Department Highest Salary *	19.00%	Medium
183	Customers Who Never Order *	33.70%	Easy
182	Duplicate Emails *	38.10%	Easy
181	Employees Earning More Than Their Managers *	41.00%	Easy
180	Consecutive Numbers *	26.60%	Medium
179	Largest Number	15.70%	Medium
178	Rank Scores *	24.60%	Medium
177	Nth Highest Salary *	16.30%	Medium
176	Second Highest Salary *	25.00%	Easy
175	Combine Two Tables *	34.40%	Easy
174	Dungeon Game	17.70%	Hard
173	Binary Search Tree Iterator	29.30%	Medium
172	Factorial Trailing Zeroes	28.40%	Easy
171	Excel Sheet Column Number	36.50%	Easy
170	Two Sum III - Data structure design $	24.70%	Easy
169	Majority Element	35.00%	Easy
168	Excel Sheet Column Title	18.10%	Easy
167	Two Sum II - Input array is sorted $	43.30%	Medium
166	Fraction to Recurring Decimal	12.70%	Medium
165	Compare Version Numbers	15.20%	Easy
164	Maximum Gap	24.40%	Hard
163	Missing Ranges $	24.10%	Medium
162	Find Peak Element	31.50%	Medium
161	One Edit Distance $	24.00%	Medium
160	Intersection of Two Linked Lists	28.70%	Easy
159	Longest Substring with At Most Two Distinct Characters $	30.20%	Hard
158	Read N Characters Given Read4 II - Call multiple times $	22.30%	Hard
157	Read N Characters Given Read4 $	29.80%	Easy
156	Binary Tree Upside Down $	34.30%	Medium
155	Min Stack	18.50%	Easy
154	Find Minimum in Rotated Sorted Array II	31.90%	Hard
153	Find Minimum in Rotated Sorted Array	33.30%	Medium
152	Maximum Product Subarray	19.40%	Medium
151	Reverse Words in a String	15.10%	Medium
150	Evaluate Reverse Polish Notation	21.10%	Medium
149	Max Points on a Line	12.60%	Hard
148	Sort List	22.00%	Medium
147	Insertion Sort List	26.40%	Medium
146	LRU Cache	15.00%	Hard
145	Binary Tree Postorder Traversal	32.40%	Hard
144	Binary Tree Preorder Traversal	36.30%	Medium
143	Reorder List	21.00%	Medium
142	Linked List Cycle II	31.40%	Medium
141	Linked List Cycle	36.30%	Medium
140	Word Break II	17.70%	Hard
139	Word Break	23.00%	Medium
138	Copy List with Random Pointer	25.10%	Hard
137	Single Number II	35.00%	Medium
136	Single Number	45.10%	Medium
135	Candy	20.50%	Hard
134	Gas Station	25.70%	Medium
133	Clone Graph	24.00%	Medium
132	Palindrome Partitioning II	19.70%	Hard
131	Palindrome Partitioning	26.70%	Medium
130	Surrounded Regions	14.60%	Medium
129	Sum Root to Leaf Numbers	30.30%	Medium
128	Longest Consecutive Sequence	29.40%	Hard
127	Word Ladder	19.30%	Medium
126	Word Ladder II	12.90%	Hard
125	Valid Palindrome	22.00%	Easy
124	Binary Tree Maximum Path Sum	21.50%	Hard
123	Best Time to Buy and Sell Stock III	23.90%	Hard
122	Best Time to Buy and Sell Stock II	38.30%	Medium
121	Best Time to Buy and Sell Stock	32.60%	Medium
120	Triangle	27.40%	Medium
119	Pascal's Triangle II	29.40%	Easy
118	Pascal's Triangle	30.10%	Easy
117	Populating Next Right Pointers in Each Node II	32.00%	Hard
116	Populating Next Right Pointers in Each Node	36.20%	Medium
115	Distinct Subsequences	26.30%	Hard
114	Flatten Binary Tree to Linked List	28.80%	Medium
113	Path Sum II	26.60%	Medium
112	Path Sum	29.80%	Easy
111	Minimum Depth of Binary Tree	29.10%	Easy
110	Balanced Binary Tree	32.00%	Easy
109	Convert Sorted List to Binary Search Tree	27.90%	Medium
108	Convert Sorted Array to Binary Search Tree	34.00%	Medium
107	Binary Tree Level Order Traversal II	31.10%	Easy
106	Construct Binary Tree from Inorder and Postorder Traversal	26.80%	Medium
105	Construct Binary Tree from Preorder and Inorder Traversal	26.40%	Medium
104	Maximum Depth of Binary Tree	45.10%	Easy
103	Binary Tree Zigzag Level Order Traversal	26.40%	Medium
102	Binary Tree Level Order Traversal	29.30%	Easy
101	Symmetric Tree	31.60%	Easy
100	Same Tree	41.80%	Easy
99	Recover Binary Search Tree	24.30%	Hard
98	Validate Binary Search Tree	20.60%	Medium
97	Interleaving String	20.80%	Hard
96	Unique Binary Search Trees	36.00%	Medium
95	Unique Binary Search Trees II	28.00%	Medium
94	Binary Tree Inorder Traversal	36.20%	Medium
93	Restore IP Addresses	21.00%	Medium
92	Reverse Linked List II	26.10%	Medium
91	Decode Ways	16.40%	Medium
90	Subsets II	27.70%	Medium
89	Gray Code	32.80%	Medium
88	Merge Sorted Array	29.70%	Easy
87	Scramble String	24.20%	Hard
86	Partition List	27.50%	Medium
85	Maximal Rectangle	22.00%	Hard
84	Largest Rectangle in Histogram	22.60%	Hard
83	Remove Duplicates from Sorted List	34.50%	Easy
82	Remove Duplicates from Sorted List II	25.00%	Medium
81	Search in Rotated Sorted Array II	31.40%	Medium
80	Remove Duplicates from Sorted Array II	30.50%	Medium
79	Word Search	20.30%	Medium
78	Subsets	28.20%	Medium
77	Combinations	30.90%	Medium
76	Minimum Window Substring	18.90%	Hard
75	Sort Colors	32.60%	Medium
74	Search a 2D Matrix	31.60%	Medium
73	Set Matrix Zeroes	31.40%	Medium
72	Edit Distance	26.20%	Hard
71	Simplify Path	20.00%	Medium
70	Climbing Stairs	34.40%	Easy
69	Sqrt(x)	23.10%	Medium
68	Text Justification	14.60%	Hard
67	Add Binary	24.70%	Easy
66	Plus One	30.40%	Easy
65	Valid Number	11.40%	Hard
64	Minimum Path Sum	32.20%	Medium
63	Unique Paths II	28.00%	Medium
62	Unique Paths	32.80%	Medium
61	Rotate List	21.70%	Medium
60	Permutation Sequence	22.80%	Medium
59	Spiral Matrix II	31.80%	Medium
58	Length of Last Word	28.00%	Easy
57	Insert Interval	21.40%	Hard
56	Merge Intervals	22.40%	Hard
55	Jump Game	27.00%	Medium
54	Spiral Matrix	20.80%	Medium
53	Maximum Subarray	34.50%	Medium
52	N-Queens II	35.80%	Hard
51	N-Queens	26.50%	Hard
50	"Pow(x	n)"	26.70%
49	Anagrams	24.30%	Medium
48	Rotate Image	31.90%	Medium
47	Permutations II	25.80%	Hard
46	Permutations	31.90%	Medium
45	Jump Game II	24.20%	Hard
44	Wildcard Matching	15.00%	Hard
43	Multiply Strings	21.00%	Medium
42	Trapping Rain Water	30.00%	Hard
41	First Missing Positive	22.90%	Hard
40	Combination Sum II	25.20%	Medium
39	Combination Sum	27.90%	Medium
38	Count and Say	25.20%	Easy
37	Sudoku Solver	21.80%	Hard
36	Valid Sudoku	27.20%	Easy
35	Search Insert Position	35.40%	Medium
34	Search for a Range	27.50%	Medium
33	Search in Rotated Sorted Array	28.80%	Hard
32	Longest Valid Parentheses	20.90%	Hard
31	Next Permutation	25.00%	Medium
30	Substring with Concatenation of All Words	19.40%	Hard
29	Divide Two Integers	15.00%	Medium
28	Implement strStr()	22.20%	Easy
27	Remove Element	32.10%	Easy
26	Remove Duplicates from Sorted Array	31.30%	Easy
25	Reverse Nodes in k-Group	25.50%	Hard
24	Swap Nodes in Pairs	32.50%	Medium
23	Merge k Sorted Lists	21.10%	Hard
22	Generate Parentheses	32.60%	Medium
21	Merge Two Sorted Lists	32.70%	Easy
20	Valid Parentheses	26.50%	Easy
19	Remove Nth Node From End of List	27.10%	Easy
18	4Sum	21.70%	Medium
17	Letter Combinations of a Phone Number	25.80%	Medium
16	3Sum Closest	26.90%	Medium
15	3Sum	16.90%	Medium
14	Longest Common Prefix	25.50%	Easy
13	Roman to Integer	34.00%	Easy
12	Integer to Roman	33.80%	Medium
11	Container With Most Water	32.00%	Medium
10	Regular Expression Matching	20.70%	Hard
9	Palindrome Number	28.30%	Easy
8	String to Integer (atoi)	13.00%	Easy
7	Reverse Integer	25.10%	Easy
6	ZigZag Conversion	21.80%	Easy
5	Longest Palindromic Substring	20.70%	Medium
4	Median of Two Sorted Arrays	17.40%	Hard
3	Longest Substring Without Repeating Characters	20.60%	Medium
2	Add Two Numbers	21.10%	Medium
1	Two Sum	17.70%	Medium

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