My Leetcode Solutions

If you have a better soluton or find an error, feel free to open a PR. Thanks.

#	Title	Solution	Difficulty
1	Two Sum	Swift	Easy
2	Add Two Numbers	Swift	Medium
3	Longest Substring Without Repeating Characters	Swift	Medium
5	Longest Palindromic Substring	Swift	Medium
7	Reverse Integer	Swift	Easy
9	Palindrome Number	Swift	Easy
11	Container With Most Water	Swift	Medium
13	Roman to Integer	Swift	Easy
15	3Sum	Swift	Medium
16	3Sum Closest	Swift	Medium
17	Letter Combinations of a Phone Number	Swift	Medium
18	4Sum	Swift	Medium
19	Remove Nth Node From End of List	Swift	Medium
20	Valid Parentheses	Swift	Easy
21	Merge Two Sorted Lists	Swift	Easy
22	Generate Parentheses	Swift	Medium
23	Merge k Sorted Lists	Swift	Hard
24	Swap Nodes in Pairs	Swift	Medium
25	Reverse Nodes in k-Group	Swift	Hard
26	Remove Duplicates from Sorted Array	Swift	Easy
27	Remove Element	Swift	Easy
28	Implement strStr()	Swift	Easy
29	Divide Two Integers	Swift	Medium
31	Next Permutation	Swift	Medium
32	Longest Valid Parentheses	Swift	Hard
33	Search in Rotated Sorted Array	Swift	Medium
34	Find First and Last Position of Element in Sorted Array	Swift	Medium
35	Search Insert Position	Swift	Easy
36	Valid Sudoku	Swift	Medium
37	Sudoku Solver	Swift	Hard
38	Count and Say	Swift	Easy
39	Combination Sum	Swift	Medium
40	Combination Sum II	Swift	Medium
41	First Missing Positive	Swift	Hard
42	Trapping Rain Water	Swift	Hard
43	Multiply Strings	Swift	Medium
46	Permutations	Swift	Medium
48	Rotate Image	Swift	Medium
49	Group Anagrams	Swift	Medium
50	Pow(x,n)	Swift	Medium
51	N-Queens	Swift, Swift,	Hard
52	N-Queens II	Swift	Hard
53	Maximum SubArray	Swift	Easy
54	Spiral Matrix	Swift	Medium
55	Jump Game	Swift	Medium
56	Merge Intervals	Swift	Medium
57	Insert Interval	Swift	Hard
59	Spiral Matrix II	Swift	Medium
60	Permutation Sequence	Swift	Medium
62	Unique Paths	Swift	Medium
63	Unique Paths II	Swift	Medium
64	Minimum Path Sum	Swift	Medium
66	Plus One	Swift	Easy
67	Add Binary	Swift	Easy
69	Sqrt(x)	Swift, Swift	Easy
70	Climbing Stairs	Swift, Swift	Easy
71	Simplify Path	Swift	Medium
72	Edit Distance	Swift	Hard
73	Set Matrix Zeroes	Swift	Medium
74	Search a 2D Matrix	Swift	Medium
75	Sort Colors	Swift	Medium
76	Minimum Window Substring	Swift	Hard
78	Subsets	Swift	Medium
79	Word Search	Swift	Medium
80	Remove Duplicates from Sorted Array II	Swift	Medium
81	Search in Rotated Sorted Array II	Swift	Medium
82	Remove Duplicates from Sorted List II	Swift	Medium
83	Remove Duplicates from Sorted List	Swift	Easy
86	Partition List	Swift	Medium
88	Merge Sorted Array	Swift	Easy
90	Subsets II	Swift	Medium
92	Reverse Linked List II	Swift	Medium
93	Restore IP Addresses	Swift	Medium
94	Binary Tree Inorder Traversal	Swift	Medium
95	Unique Binary Search Trees II	Swift	Medium
96	Unique Binary Search Trees	Swift	Medium
98	Validate Binary Search Tree	Swift	Medium
100	Same Tree	Swift	Easy
101	Symmetric Tree	Swift	Easy
102	Binary Tree Level Order Traversal	Swift	Medium
103	Binary Tree Zigzag Level Order Traversal	Swift	Medium
104	Maximum Depth of Binary Tree	Swift	Easy
105	Construct Binary Tree from Preorder and Inorder Traversal	Swift	Medium
106	Construct Binary Tree from Inorder and Postorder Traversal	Swift	Medium
107	Binary Tree Level Order Traversal II	Swift	Easy
108	Convert Sorted Array to Binary Search Tree	Swift	Easy
109	Convert Sorted List to Binary Search Tree	Swift	Medium
110	Balanced Binary Tree	Swift	Easy
111	Minimum Depth of Binary Tree	Swift	Easy
112	Path Sum	Swift	Easy
113	Path Sum II	Swift	Medium
116	Populating Next Right Pointers in Each Node	Swift	Medium
117	Populating Next Right Pointers in Each Node II	Swift	Medium
118	Pascal's Triangle	Swift	Easy
119	Pascal's Triangle II	Swift	Easy
120	Triangle	Swift	Medium
121	Best Time to Buy and Sell Stock	Swift	Easy
122	Best Time to Buy and Sell Stock II	Swift, Swift	Easy
123	Best Time to Buy and Sell Stock III	Swift, Swift	Hard
124	Binary Tree Maximum Path Sum	Swift	Hard
125	Valid Palindrome	Swift	Easy
129	Sum Root to Leaf Numbers	Swift	Medium
130	Surrounded Regions	Swift	Medium
136	Single Number	Swift	Easy
137	Single Number II	Swift	Medium
139	Word Break	Swift	Medium
141	Linked List Cycle	Swift	Easy
142	Linked List Cycle II	Swift	Medium
143	Reorder List	Swift	Medium
144	Binary Tree Preorder Traversal	Swift	Medium
145	Binary Tree Postorder Traversal	Swift	Hard
146	LRU Cache	Swift	Medium
147	Insertion Sort List	Swift	Medium
148	Sort List	Swift	Medium
150	Evaluate Reverse Polish Notation	Swift	Medium
152	Maximum Product Subarray	Swift, Swift	Medium
153	Find Minimum in Rotated Sorted Array	Swift	Medium
155	Min Stack	Swift	Easy
156	Binary Tree Upside Down	Swift	Medium
159	Longest Substring with At Most Two Distinct Characters	Swift	Medium
162	Find Peak Element	Swift	Medium
163	Missing Ranges	Swift	Medium
167	Two Sum II - input array is sorted	Swift	Easy
169	Majority Element	Swift	Easy
171	Excel Sheet Column Number	Swift	Easy
173	Binary Search Tree Iterator	Swift	Medium
174	Dungeon Gamer	Swift	Hard
189	Rotate Array	Swift	Easy
191	Number of 1 Bits	Swift	Easy
199	Binary Tree Right Side View	Swift	Medium
200	Number of Islands	Swift	Medium
201	Bitwise AND of Numbers Range	Swift	Medium
202	Happy Number	Swift	Easy
203	Remove Linked List Element	Swift	Easy
206	Reverse Linked List	Swift, Swift, Swift, Swift	Easy
207	Course Schedule	Swift	Medium
208	Implement Trie (Prefix Tree)	Swift	Medium
209	Minimum Size Subarray Sum	Swift	Medium
210	Course Schedule II	Swift	Medium
211	Add and Search Word - Data structure design	Swift	Medium
212	Word Search II	Swift	Hard
215	Kth Largest Element in an Array	Swift	Medium
216	Combination Sum III	Swift	Medium
217	Contains Duplicate	Swift	Easy
219	Contains Duplicate II	Swift	Easy
221	Maximal Square	Swift	Medium
222	Count Complete Tree Nodes	Swift	Medium
223	Rectangle Area	Swift	Medium
224	Basic Calculator	Swift	Hard
225	Implement Stack using Queue	Swift	Easy
226	Invert Binary Tree	Swift	Easy
227	Basic Calculator II	Swift	Medium
228	Summary Ranges	Swift	Medium
229	Majority Element II	Swift	Medium
230	Kth Smallest Element in a BST	Swift	Medium
231	Power of Two	Swift	Easy
232	Implement Queue using Stacks	Swift	Easy
234	Palindrome Linked List	Swift	Easy
235	Lowest Common Ancestor of a Binary Search Tree	Swift	Easy
236	Lowest Common Ancestor of a Binary Tree	Swift	Medium
237	Delete Node in a Linked List	Swift	Easy
238	Product of Array Except Self	Swift	Medium
239	Sliding Window Maximum	Swift, Swift,Swift	Hard
240	Search a 2D Matrix II	Swift	Medium
242	Valid Anagram	Swift, Swift	Easy
243	Shortest Word Distance	Swift	Easy
246	Strobogrammatic Number	Swift	Easy
247	Strobogrammatic Number II	Swift	Medium
249	Group Shifted Strings	Swift	Medium
250	Count Univalue Subtrees	Swift	Medium
252	Meeting Rooms	Swift	Easy
253	Meeting Rooms II	Swift	Medium
255	Verify Preorder Sequence in Binary Search Tree	Swift	Medium
257	Binary Tree Paths	Swift	Easy
259	3Sum Smaller	Swift	Medium
264	Ugly Number II	Swift	Medium
266	Palindrome Permutation	Swift	Easy
268	Missing Number	Swift	Easy
270	Closest Binary Search Tree Value	Swift	Easy
275	H-Index II	Swift	Medium
276	Paint Fence	Swift	Easy
279	Perfect Squares	Swift	Medium
280	Wiggle Sort	Swift	Medium
283	Move Zeroes	Swift	Easy
285	Inorder Successor in BST	Swift	Medium
286	Walls and Gates	Swift	Medium
287	Find the Duplicate Number	Swift, Swift	Medium
289	Game of Life	Swift	Medium
295	Find Median from Data Stream	Swift	Hard
297	Serialize and Deserialize Binary Tree	Swift	Medium
298	Binary Tree Longest Consecutive Sequence	Swift	Medium
300	Longest Increasing Subsequence	Swift, Swift	Medium
303	Range Sum Query - Immutable	Swift	Easy
304	Range Sum Query 2D - Immutable	Swift	Medium
311	Sparse Matrix Multiplication	Swift	Medium
314	Binary Tree Vertical Order Traversal	Swift	Medium
319	Bulb Switcher	Swift	Medium
322	Coin Change	Swift	Medium
325	Maximum Size Subarray Sum Equals k	Swift	Medium
328	Odd Even Linked List	Swift	Medium
329	Longest Increasing Path in a Matrix	Swift	Hard
331	Verify Preorder Serialization of a Binary Tree	Swift	Medium
332	Reconstruct Itinerary	Swift	Medium
333	Largest BST Subtree	Swift	Medium
334	Increasing Triplet Subsequence	Swift	Medium
337	House Robber III	Swift	Medium
338	Counting Bits	Swift	Medium
339	Nested List Weight Sum	Swift	Easy
340	Longest Substring with At Most K Distinct Characters	Swift	Hard
341	Flatten Nested List Iterator	Swift	Medium
344	Reverse String	Swift	Easy
345	Reverse Vowels of a String	Swift	Easy
346	Moving Average from Data Stream	Swift	Easy
347	Top K Frequent Elements	Swift	Medium
348	Design Tic-Tac-Toe	Swift	Medium
349	Intersection of Two Arrays	Swift	Easy
350	Intersection of Two Arrays II	Swift	Easy
353	Design Snake Game	Swift	Medium
360	Sort Transformed Array	Swift	Medium
362	Design Hit Counter	Swift	Medium
366	Find Leaves of Binary Tree	Swift	Medium
367	Valid Perfect Square	Swift	Easy
368	Largest Divisible Subset	Swift	Medium
369	Plus One Linked List	Swift	Medium
373	Find K Pairs with Smallest Sums	Swift	Medium
378	Kth Smallest Element in a Sorted Matrix	Swift	Medium
379	Design Phone Directory	Swift	Medium
380	Insert Delete GetRandom O(1)	Swift	Medium
383	Ransom Note	Swift	Easy
384	Shuffle an Array	Swift	Medium
385	Mini Parser	Swift	Medium
387	First Unique Character in a String	Swift	Easy
392	Is Subsequence	Swift	Easy
394	Decode String	Swift	Medium
398	Random Pick Index	Swift	Medium
402	Remove K Digits	Swift	Medium
404	Sum of Left Leaves	Swift	Easy
406	Queue Reconstruction by Height	Swift	Medium
407	Trapping Rain Water II	Swift	Hard
414	Third Maximum Number	Swift	Easy
415	Add Strings	Swift	Easy
416	Partition Equal Subset Sum	Swift	Medium
419	Battleships in a Board	Swift	Medium
424	Longest Repeating Character Replacement	Swift	Medium
429	N-ary Tree Level Order Traversal	Swift	Medium
437	Path Sum III	Swift	Easy
438	Find All Anagrams in a String	Swift	Medium
439	Ternary Expression Parser	Swift	Medium
441	Arranging Coins	Swift	Easy
442	Find All Duplicates in an Array	Swift	Medium
445	Add Two Numbers II	Swift	Medium
448	Find All Numbers Disappeared in an Array	Swift	Easy
449	Serialize and Deserialize BST	Swift	Medium
450	Delete Node in a BST	Swift	Medium
451	Sort Characters By Frequency	Swift	Medium
452	Minimum Number of Arrows to Burst Balloons	Swift	Medium
456	132 Pattern	Swift	Medium
457	Circular Array Loop	Swift	Medium
461	Hamming Distance	Swift	Easy
463	Island Perimeter	Swift	Easy
468	Validate IP Address	Swift	Medium
476	Number Complement	Swift	Easy
485	Max Consecutive Ones	Swift	Easy
487	Max Consecutive Ones II	Swift	Medium
490	The Maze	Swift	Medium
494	Target Sum	Swift	Medium
496	Next Greater Element I	Swift	Easy
498	Diagonal Traverse	Swift	Medium
501	Find Mode in Binary Search Tree	Swift	Easy
503	Next Greater Element II	Swift	Medium
508	Most Frequent Subtree Sum	Swift	Medium
509	Fibonacci Number	Swift	Easy
510	Inorder Successor in BST II	Swift	Medium
513	Find Bottom Left Tree Value	Swift	Medium
515	Find Largest Value in Each Tree Row	Swift	Medium
518	Coin Change 2	Swift	Medium
523	Continuous Subarray Sum	Swift	Medium
524	Longest Word in Dictionary through Deleting	Swift	Medium
525	Contiguous Array	Swift	Medium
528	Random Pick with Weight	Swift	Medium
529	Minesweeper	Swift	Medium
530	Minimum Absolute Difference in BST	Swift	Easy
532	K-diff Pairs in an Array	Swift	Easy
536	Construct Binary Tree from String	Swift	Medium
538	Convert BST to Greater Tree	Swift	Easy
540	Single Element in a Sorted Array	Swift	Medium
543	Diameter of Binary Tree	Swift	Easy
545	Boundary of Binary Tree	Swift	Medium
547	Friend Circles	Swift	Medium
549	Binary Tree Longest Consecutive Sequence II	Swift	Medium
559	Maximum Depth of N-ary Tree	Swift	Medium
560	Subarray Sum Equals K	Swift	Medium
561	Array Partition I	Swift	Easy
563	Binary Tree Tilt	Swift	Easy
565	Array Nesting	Swift	Medium
566	Reshape the Matrix	Swift	Easy
567	Permutation in String	Swift	Medium
572	Subtree of Another Tree	Swift	Easy
581	Shortest Unsorted Continuous Subarray	Swift, Swift	Easy
582	Kill Process	Swift	Medium
589	N-ary Tree Preorder Traversal	Swift	Easy
590	N-ary Tree Postorder Traversal	Swift, Swift	Easy
605	Can Place Flowers	Swift	Easy
606	Construct String from Binary Tree	Swift	Easy
611	Valid Triangle Number	Swift	Medium
616	Add Bold Tag in String	Swift	Medium
617	Merge Two Binary Trees	Swift	Easy
621	Task Scheduler	Swift	Medium
622	Design Circular Queue	Swift	Medium
623	Add One Row to Tree	Swift	Medium
628	Maximum Product of Three Numbers	Swift	Easy
630	Course Schedule III	Swift	Hard
636	Exclusive Time of Functions	Swift	Medium
637	Average of Levels in Binary Tree	Swift	Easy
641	Design Circular Deque	Swift	Medium
643	Maximum Average Subarray I	Swift	Easy
647	Palindromic Substrings	Swift	Medium
652	Find Duplicate Subtrees	Swift	Medium
653	Two Sum IV - Input is a BST	Swift	Easy
654	Maximum Binary Tree	Swift	Medium
655	Print Binary Tree	Swift	Medium
658	Find K Closest Elements	Swift	Medium
661	Image Smoother	Swift	Easy
662	Maximum Width of Binary Tree	Swift	Medium
663	Equal Tree Partition	Swift	Medium
665	Non-decreasing Array	Swift	Easy
666	Path Sum IV	Swift	Medium
667	Beautiful Arrangement II	Swift	Medium
669	Trim a Binary Search Tree	Swift	Easy
670	Maximum Swap	Swift	Medium
671	Second Minimum Node In a Binary Tree	Swift	Easy
674	Longest Continuous Increasing Subsequence	Swift	Easy
678	Valid Parenthesis String	Swift	Medium
680	Valid Palindrome II	Swift	Easy
682	Baseball Game	Swift	Medium
684	Redundant Connection	Swift	Medium
687	Longest Univalue Path	Swift	Easy
690	Employee Importance	Swift	Easy
692	Top K Frequent Words	Swift	Medium
695	Max Area of Island	Swift	Medium
697	Degree of an Array	Swift	Easy
700	Search in a Binary Search Tree	Swift	Easy
701	Insert into a Binary Search Tree	Swift	Medium
703	Kth Largest Element in a Stream	Swift	Easy
704	Binary Search	Swift	Easy
713	Subarray Product Less Than K	Swift	Medium
714	Best Time to Buy and Sell Stock with Transaction Fee	Swift	Medium
717	1-bit and 2-bit Characters	Swift	Easy
718	Maximum Length of Repeated Subarray	Swift	Medium
721	Accounts Merge	Swift	Medium
723	Candy Crush	Swift	Medium
724	Find Pivot Index	Swift	Easy
725	Split Linked List in Parts	Swift	Medium
729	My Calendar I	Swift	Medium
733	Flood Fill	Swift	Easy
735	Asteroid Collision	Swift	Medium
739	Daily Temperatures	Swift	Medium
742	Closest Leaf in a Binary Tree	Swift	Medium
743	Network Delay Time	Swift	Medium
744	Find Smallest Letter Greater Than Target	Swift	Easy
746	Min Cost Climbing Stairs	Swift	Easy
747	Largest Number At Least Twice of Others	Swift	Easy
750	Number Of Corner Rectangles	Swift	Medium
763	Partition Labels	Swift	Medium
766	Toeplitz Matrix	Swift	Easy
767	Reorganize String	Swift	Medium
769	Max Chunks To Make Sorted	Swift	Medium
771	Jewels and Stones	Swift	Easy
776	Split BST	Swift	Medium
783	Minimum Distance Between BST Nodes	Swift	Easy
784	Letter Case Permutation	Swift	Easy
785	Is Graph Bipartite?	Swift	Medium
787	Cheapest Flights Within K Stops	Swift	Medium
788	Rotated Digits	Swift	Medium
792	Number of Matching Subsequences	Swift	Medium
814	Binary Tree Pruning	Swift	Medium
817	Linked List Components	Swift	Medium
821	Shortest Distance to a Character	Swift	Easy
824	Goat Latin	Swift	Easy
825	Friends Of Appropriate Ages	Swift	Medium
826	Most Profit Assigning Work	Swift	Medium
832	Flipping an Image	Swift	Easy
838	Push Dominoes	Swift	Medium
844	Backspace String Compare	Swift	Easy
845	Longest Mountain in Array	Swift	Medium
849	Maximize Distance to Closest Person	Swift	Easy
856	Score of Parentheses	Swift	Medium
865	Smallest Subtree with all the Deepest Nodes	Swift	Medium
867	Transpose Matrix	Swift	Easy
871	Minimum Number of Refueling Stops	Swift, Swift	Hard
872	Leaf-Similar Trees	Swift	Easy
876	Middle of the Linked List	Swift	Easy
877	Stone Game	Swift	Medium
880	Decoded String at Index	Swift	Medium
881	Boats to Save People	Swift	Medium
886	Possible Bipartition	Swift	Medium
888	Fair Candy Swap	Swift	Easy
889	Construct Binary Tree from Preorder and Postorder Traversal	Swift	Medium
894	All Possible Full Binary Trees	Swift	Easy
896	Monotonic Array	Swift	Easy
897	Increasing Order Search Tree	Swift	Easy
901	Online Stock Span	Swift	Medium
904	Fruit Into Baskets	Swift	Medium
905	Sort Array By Parity	Swift	Easy
907	Sum of Subarray Minimus	Swift	Medium
918	Maximum Sum Circular Subarray	Swift	Medium
919	Complete Binary Tree Inserter	Swift	Medium
921	Minimum Add to Make Parentheses Valid	Swift	Medium
922	Sort Array By Parity II	Swift	Easy
923	3Sum With Multiplicity	Swift	Medium
925	Long Pressed Name	Swift	Easy
930	Binary Subarrays With Sum	Swift	Medium
931	Minimum Falling Path Sum	Swift	Medium
933	Number of Recent Calls	Swift	Easy
937	Reorder Data in Log Files	Swift	Easy
938	Range Sum of BST	Swift	Easy
946	Validate Stack Sequences	Swift	Medium
950	Reveal Cards In Increasing Order	Swift	Medium
951	Flip Equivalent Binary Trees	Swift	Medium
953	Verifying an Alien Dictionary	Swift	Easy
957	Prison Cells After N Days	Swift	Medium
958	Check Completeness of a Binary Tree	Swift	Medium
965	Univalued Binary Tree	Swift	Easy
969	Pancake Sorting	Swift	Medium
971	Flip Binary Tree To Match Preorder Traversal	Swift	Medium
973	K Closest Points to Origin	Swift	Medium
974	Subarray Sums Divisible by K	Swift	Medium
977	Squares of a Sorted Array	Swift	Easy
979	Distribute Coins in Binary Tree	Swift	Medium
981	Time Based Key-Value Store	Swift	Medium
983	Minimum Cost For Tickets	Swift	Medium
986	Interval List Intersections	Swift	Medium
987	Vertical Order Traversal of a Binary Tree	Swift	Medium
988	Smallest String Starting From Leaf	Swift	Medium
993	Cousins in Binary Tree	Swift	Easy
997	Find the Town Judge	Swift	Easy
998	Maximum Binary Tree II	Swift	Medium
1002	Find Common Characters	Swift	Easy
1003	Check If Word Is Valid After Substitutions	Swift	Medium
1004	Max Consecutive Ones III	Swift	Medium
1008	Construct Binary Search Tree from Preorder Traversal	Swift	Medium
1010	Pairs of Songs With Total Durations Divisible by 60	Swift	Easy
1011	Capacity To Ship Packages Within D Days	Swift	Medium
1013	Partition Array Into Three Parts With Equal Sum	Swift	Easy
1019	Next Greater Node In Linked List	Swift	Medium
1021	Remove Outermost Parentheses	Swift	Easy
1022	Sum of Root To Leaf Binary Numbers	Swift	Easy
1025	Divisor Game	Swift	Easy
1026	Maximum Difference Between Node and Ancestor	Swift	Medium
1027	Longest Arithmetic Sequence	Swift	Medium
1029	Two City Scheduling	Swift	Easy
1030	Minimum Cost Tree From Leaf Values	Swift	Medium
1031	Maximum Sum of Two Non-Overlapping Subarrays	Swift	Medium
1035	Uncrossed Lines	Swift	Medium
1043	Partition Array for Maximum Sum	Swift	Medium
1046	Last Stone Weight	Swift	Easy
1047	Remove All Adjacent Duplicates In String	Swift	Easy
1051	Height Checker	Swift	Easy
1060	Missing Element in Sorted Array	Swift	Medium
1086	High Five	Swift	Easy
1089	Duplicate Zeros	Swift	Easy
1093	Statistics from a Large Sample	Swift	Medium
1094	Car Pooling	Swift	Medium
1104	Path In Zigzag Labelled Binary Tree	Swift	Medium
1110	Delete Nodes And Return Forest	Swift	Medium
1119	Remove Vowels from a String	Swift	Easy
1120	Maximum Average Subtree	Swift	Medium
1123	Lowest Common Ancestor of Deepest Leaves	Swift	Medium
1124	Longest Well-Performing Interval	Swift	Medium
1130	Minimum Cost Tree From Leaf Values	Swift	Medium
1143	Longest Common Subsequence	Swift	Medium
1145	Binary Tree Coloring Game	Swift	Medium
1146	Snapshot Array	Swift	Medium
1171	Remove Zero Sum Consecutive Nodes from Linked List	Swift	Medium
1190	Reverse Substrings Between Each Pair of Parentheses	Swift	Medium
1197	Minimum Knight Moves	Swift	Medium
1209	Remove All Adjacent Duplicates in String II	Swift	Medium
1213	Intersection of Three Sorted Arrays	Swift	Easy
1217	Play with Chips	Swift	Easy
1218	Longest Arithmetic Subsequence of Given Difference	Swift	Medium
1219	Path with Maximum Gold	Swift	Medium
1221	Split a String in Balanced Strings	Swift	Easy
1232	Check If It Is a Straight Line	Swift	Easy
1234	Replace the Substring for Balanced String	Swift	Medium
1245	Tree Diameter	Swift	Medium
1248	Count Number of Nice Subarrays	Swift	Medium
1249	Minimum Remove to Make Valid Parentheses	Swift	Medium
1257	Smallest Common Region	Swift	Medium
1261	Find Elements in a Contaminated Binary Tree	Swift	Medium
1273	Delete Tree Nodes	Swift	Medium
1275	Find Winner on a Tic Tac Toe Game	Swift	Easy
1277	Count Square Submatrices with All Ones	Swift	Medium
1290	Convert Binary Number in a Linked List to Integer	Swift	Easy
1302	Deepest Leaves Sum	Swift	Medium
1314	Matrix Block Sum	Swift	Medium
1315	Sum of Nodes with Even-Valued Grandparent	Swift	Medium
1317	Convert Integer to the Sum of Two No-Zero Integers	Swift	Easy
1318	Minimum Flips to Make a OR b Equal to c	Swift	Medium
1319	Number of Operations to Make Network Connected	Swift	Medium
1325	Delete Leaves With a Given Value	Swift	Medium
1329	Sort the Matrix Diagonally	Swift	Medium
1339	Maximum Product of Splitted Binary Tree	Swift	Medium
1366	Rank Teams by Votes	Swift	Medium
1367	Linked List in Binary Tree	Swift	Medium
1372	Longest ZigZag Path in a Binary Tree	Swift	Medium
1381	Design a Stack With Increment Operation	Swift	Medium
1395	Count Number of Teams	Swift	Medium
1410	HTML Entity Parser	Swift	Medium
1413	Minimum Value to Get Positive Step by Step Sum	Swift	Easy
1423	Maximum Points You Can Obtain from Cards	Swift	Medium
1424	Diagonal Traverse II	Swift	Medium
1426	Counting elements	Swift	Easy
1427	Perform String Shifts	Swift	Easy
1428	Leftmost Column with at Least a One	Swift, Swift	Medium
1429	First Unique Number	Swift	Medium
1430	Check If a String Is a Valid Sequence from Root to Leaves Path in a Binary Tree	Swift	Medium
1431	Kids With the Greatest Number of Candies	Swift	Easy
1438	Longest Continuous Subarray With Absolute Diff Less Than or Equal to Limit	Swift	Medium
1441	Build an Array With Stack Operations	Swift	Easy
1443	Minimum Time to Collect All Apples in a Tree	Swift	Medium
1448	Count Good Nodes in Binary Tree	Swift	Medium
1457	Pseudo-Palindromic Paths in a Binary Tree	Swift	Medium
1466	Reorder Routes to Make All Paths Lead to the City Zero	Swift	Medium
1469	Find All The Lonely Nodes	Swift	Medium
1470	Shuffle the Array	Swift	Easy
1474	Delete N Nodes After M Nodes of a Linked List	Swift	Easy
1480	Running Sum of 1d Array	Swift	Easy
1485	Clone Binary Tree With Random Pointer	Swift	Medium
1490	Clone N-ary Tree	Swift	Medium
1497	Check If Array Pairs Are Divisible by k	Swift	Medium
1512	Number of Good Pairs	Swift	Medium
1530	Number of Good Leaf Nodes Pairs	Swift	Medium
1541	Minimum Insertions to Balance a Parentheses String	Swift	Medium
1544	Make The String Great	Swift	Easy
1570	Dot Product of Two Sparse Vectors	Swift	Medium
1603	Design Parking System	Swift	Easy
1614	Maximum Nesting Depth of the Parentheses	Swift	Easy
1615	Maximal Network Rank	Swift	Medium
1616	Split Two Strings to Make Palindrome	Swift	Medium
1624	Largest Substring Between Two Equal Characters	Swift	Easy
1626	Best Team With No Conflicts	Swift	Medium
1627	Graph Connectivity With Threshold	Swift	Hard
1629	Slowest Key	Swift	Easy
1630	Arithmetic Subarrays	Swift	Medium
1631	Path With Minimum Effort	Swift	Medium
1636	Sort Array by Increasing Frequency	Swift	Easy
1637	Widest Vertical Area Between Two Points Containing No Points	Swift	Medium
1638	Count Substrings That Differ by One Character	Swift	Medium
1640	Check Array Formation Through Concatenation	Swift	Easy
1641	Count Sorted Vowel Strings	Swift	Medium
1642	Furthest Building You Can Reach	Swift	Medium
1646	Get Maximum in Generated Array	Swift	Easy
1647	Minimum Deletions to Make Character Frequencies Unique	Swift	Medium
1648	Sell Diminishing-Valued Colored Balls	Swift	Medium
1652	Defuse the Bomb	Swift	Easy
1653	Minimum Deletions to Make String Balanced	Swift	Medium
1656	Design an Ordered Stream	Swift	Easy
1657	Determine if Two Strings Are Close	Swift	Medium
1658	Minimum Operations to Reduce X to Zero	Swift	Medium
1688	Count of Matches in Tournament	Swift	Easy
1689	Partitioning Into Minimum Number Of Deci-Binary Numbers	Swift	Medium
1690	Stone Game VII	Swift, Swift, Swift	Medium
1691	Maximum Height by Stacking Cuboids	Swift	Medium
1672	Richest Customer Wealth	Swift	Easy
1746	Maximum Subarray Sum After One Operation	Swift	Medium

Categories

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K-way Merge
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Algorithms

Other Swift Algorithms Repo

• BTree: Fast ordered collections for Swift using in-memory B-trees
• JXSort
• stanfordacm: Stanford ACM-ICPC related materials
• Top 20 dynamic programming interview questions
• Majority Voting Algorithm

Posts

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Courses

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