LeetCode solutions in JavaScript

https://leetcode.com/

Table of Contents:

#	Title	Difficulty
1	Two Sum	Easy
2	Add Two Numbers	Medium
3	Longest Substring Without Repeating Characters	Medium
4	Median of Two Sorted Arrays	Hard
5	Longest Palindromic Substring	Medium
6	ZigZag Conversion	Medium
7	Reverse Integer	Easy
8	String to Integer (atoi)	Medium
9	Palindrome Number	Easy
10	Regular Expression Matching	Hard
11	Container With Most Water	Medium
12	Integer to Roman	Medium
13	Roman to Integer	Easy
14	Longest Common Prefix	Easy
15	3Sum	Medium
16	3Sum Closest	Medium
17	Letter Combinations of a Phone Number	Medium
18	4Sum	Medium
19	Remove Nth Node From End of List	Medium
20	Valid Parentheses	Easy
21	Merge Two Sorted Lists	Easy
22	Generate Parentheses	Medium
23	Merge k Sorted Lists	Hard
24	Swap Nodes in Pairs	Medium
25	Reverse Nodes in k-Group	Hard
26	Remove Duplicates from Sorted Array	Easy
27	Remove Element	Easy
28	Implement strStr()	Easy
29	Divide Two Integers	Medium
30	Substring with Concatenation of All Words	Hard
31	Next Permutation	Medium
32	Longest Valid Parentheses	Hard
33	Search in Rotated Sorted Array	Medium
34	Find First and Last Position of Element in Sorted Array	Medium
35	Search Insert Position	Easy
36	Valid Sudoku	Medium
37	Sudoku Solver	Hard
38	Count and Say	Medium
39	Combination Sum	Medium
40	Combination Sum II	Medium
41	First Missing Positive	Hard
42	Trapping Rain Water	Hard
43	Multiply Strings	Medium
44	Wildcard Matching	Hard
45	Jump Game II	Medium
46	Permutations	Medium
47	Permutations II	Medium
48	Rotate Image	Medium
49	Group Anagrams	Medium
50	Pow(x, n)	Medium
51	N-Queens	Hard
52	N-Queens II	Hard
53	Maximum Subarray	Easy
54	Spiral Matrix	Medium
55	Jump Game	Medium
56	Merge Intervals	Medium
57	Insert Interval	Medium
58	Length of Last Word	Easy
59	Spiral Matrix II	Medium
60	Permutation Sequence	Hard
61	Rotate List	Medium
62	Unique Paths	Medium
63	Unique Paths II	Medium
64	Minimum Path Sum	Medium
65	Valid Number	Hard
66	Plus One	Easy
67	Add Binary	Easy
68	Text Justification	Hard
69	Sqrt(x)	Medium
70	Climbing Stairs	Easy
71	Simplify Path	Medium
72	Edit Distance	Medium
73	Set Matrix Zeroes	Medium
74	Search a 2D Matrix	Medium
75	Sort Colors	Medium
77	Combinations	Medium
78	Subsets	Medium
79	Word Search	Medium
80	Remove Duplicates from Sorted Array II	Medium
81	Search in Rotated Sorted Array II	Medium
82	Remove Duplicates from Sorted List II	Medium
83	Remove Duplicates from Sorted List	Easy
84	Largest Rectangle in Histogram	Hard
85	Maximal Rectangle	Hard
86	Partition List	Medium
88	Merge Sorted Array	Easy
89	Gray Code	Medium
90	Subsets II	Medium
92	Reverse Linked List II	Medium
93	Restore IP Addresses	Medium
94	Binary Tree Inorder Traversal	Easy
95	Unique Binary Search Trees II	Medium
96	Unique Binary Search Trees	Medium
98	Validate Binary Search Tree	Medium
99	Recover Binary Search Tree	Medium
100	Same Tree	Easy
101	Symmetric Tree	Easy
102	Binary Tree Level Order Traversal	Medium
104	Maximum Depth of Binary Tree	Easy
108	Convert Sorted Array to Binary Search Tree	Easy
110	Balanced Binary Tree	Easy
111	Minimum Depth of Binary Tree	Easy
112	Path Sum	Easy
113	Path Sum II	Medium
114	Flatten Binary Tree to Linked List	Medium
115	Distinct Subsequences	Hard
116	Populating Next Right Pointers in Each Node	Medium
118	Pascal's Triangle	Easy
119	Pascal's Triangle II	Easy
120	Triangle	Medium
121	Best Time to Buy and Sell Stock	Easy
125	Valid Palindrome	Easy
128	Longest Consecutive Sequence	Medium
131	Palindrome Partitioning	Medium
133	Clone Graph	Medium
134	Gas Station	Medium
135	Candy	Hard
136	Single Number	Easy
137	Single Number II	Medium
138	Copy List with Random Pointer	Medium
139	Word Break	Medium
140	Word Break II	Hard
141	Linked List Cycle	Easy
142	Linked List Cycle II	Medium
143	Reorder List	Medium
144	Binary Tree Preorder Traversal	Easy
145	Binary Tree Postorder Traversal	Easy
146	LRU Cache	Medium
148	Sort List	Medium
149	Max Points on a Line	Hard
151	Reverse Words in a String	Medium
152	Maximum Product Subarray	Medium
160	Intersection of Two Linked Lists	Medium
164	Maximum Gap	Medium
167	Two Sum II - Input Array Is Sorted	Easy
168	Excel Sheet Column Title	Easy
169	Majority Element	Easy
179	Largest Number	Medium
187	Repeated DNA Sequences	Medium
189	Rotate Array	Medium
190	Reverse Bits	Easy
191	Number of 1 Bits	Easy
198	House Robber	Medium
202	Happy Number	Easy
203	Remove Linked List Elements	Easy
204	Count Primes	Medium
205	Isomorphic Strings	Easy
206	Reverse Linked List	Easy
207	Course Schedule	Medium
213	House Robber II	Medium
214	Shortest Palindrome	Hard
215	Kth Largest Element in an Array	Medium
216	Combination Sum III	Medium
217	Contains Duplicate	Easy
219	Contains Duplicate II	Easy
220	Contains Duplicate III	Hard
225	Implement Stack using Queues	Easy
226	Invert Binary Tree	Easy
229	Majority Element II	Medium
231	Power of Two	Easy
232	Implement Queue using Stacks	Easy
234	Palindrome Linked List	Easy
235	Lowest Common Ancestor of a Binary Search Tree	Easy
237	Delete Node in a Linked List	Easy
238	Product of Array Except Self	Medium
242	Valid Anagram	Easy
263	Ugly Number	Easy
264	Ugly Number II	Medium
268	Missing Number	Easy
273	Integer to English Words	Hard
274	H-Index	Medium
278	First Bad Version	Medium
283	Move Zeroes	Easy
290	Word Pattern	Easy
295	Find Median from Data Stream	Hard
316	Remove Duplicate Letters	Medium
326	Power of Three	Easy
328	Odd Even Linked List	Medium
334	Increasing Triplet Subsequence	Medium
338	Counting Bits	Easy
342	Power of Four	Easy
344	Reverse String	Easy
345	Reverse Vowels of a String	Easy
347	Top K Frequent Elements	Medium
349	Intersection of Two Arrays	Easy
350	Intersection of Two Arrays II	Easy
367	Valid Perfect Square	Easy
371	Sum of Two Integers	Medium
372	Super Pow	Medium
374	Guess Number Higher or Lower	Medium
383	Ransom Note	Easy
387	First Unique Character in a String	Easy
389	Find the Difference	Easy
392	Is Subsequence	Easy
394	Decode String	Medium
395	Longest Substring with At Least K Repeating Characters	Medium
405	Convert a Number to Hexadecimal	Easy
407	Trapping Rain Water II	Hard
412	Fizz Buzz	Easy
414	Third Maximum Number	Easy
415	Add Strings	Easy
419	Battleships in a Board	Medium
435	Non-overlapping Intervals	Medium
442	Find All Duplicates in an Array	Medium
443	String Compression	Medium
448	Find All Numbers Disappeared in an Array	Easy
451	Sort Characters By Frequency	Medium
452	Minimum Number of Arrows to Burst Balloons	Medium
456	132 Pattern	Medium
459	Repeated Substring Pattern	Easy
461	Hamming Distance	Easy
463	Island Perimeter	Medium
476	Number Complement	Easy
482	License Key Formatting	Easy
485	Max Consecutive Ones	Easy
491	Non-decreasing Subsequences	Medium
492	Construct the Rectangle	Easy
496	Next Greater Element I	Easy
500	Keyboard Row	Easy
501	Find Mode in Binary Search Tree	Easy
502	IPO	Hard
503	Next Greater Element II	Medium
504	Base 7	Easy
506	Relative Ranks	Easy
507	Perfect Number	Easy
509	Fibonacci Number	Easy
520	Detect Capital	Easy
521	Longest Uncommon Subsequence I	Easy
541	Reverse String II	Easy
542	01 Matrix	Medium
547	Number of Provinces	Medium
551	Student Attendance Record I	Easy
557	Reverse Words in a String III	Easy
563	Binary Tree Tilt	Easy
565	Array Nesting	Medium
566	Reshape the Matrix	Easy
567	Permutation in String	Medium
575	Distribute Candies	Easy
594	Longest Harmonious Subsequence	Easy
599	Minimum Index Sum of Two Lists	Easy
605	Can Place Flowers	Easy
606	Construct String from Binary Tree	Easy
617	Merge Two Binary Trees	Easy
621	Task Scheduler	Medium
628	Maximum Product of Three Numbers	Easy
643	Maximum Average Subarray I	Easy
645	Set Mismatch	Medium
648	Replace Words	Medium
649	Dota2 Senate	Medium
653	Two Sum IV - Input is a BST	Easy
680	Valid Palindrome II	Easy
686	Repeated String Match	Easy
695	Max Area of Island	Medium
697	Degree of an Array	Easy
700	Search in a Binary Search Tree	Easy
701	Insert into a Binary Search Tree	Medium
704	Binary Search	Easy
705	Design HashSet	Easy
706	Design HashMap	Easy
713	Subarray Product Less Than K	Medium
722	Remove Comments	Medium
724	Find Pivot Index	Easy
733	Flood Fill	Easy
735	Asteroid Collision	Medium
739	Daily Temperatures	Medium
746	Min Cost Climbing Stairs	Easy
747	Largest Number At Least Twice of Others	Easy
762	Prime Number of Set Bits in Binary Representation	Easy
784	Letter Case Permutation	Medium
791	Custom Sort String	Medium
796	Rotate String	Easy
804	Unique Morse Code Words	Easy
819	Most Common Word	Easy
821	Shortest Distance to a Character	Easy
824	Goat Latin	Easy
831	Masking Personal Information	Medium
841	Keys and Rooms	Medium
844	Backspace String Compare	Easy
846	Hand of Straights	Medium
867	Transpose Matrix	Easy
868	Binary Gap	Easy
872	Leaf-Similar Trees	Easy
876	Middle of the Linked List	Easy
884	Uncommon Words from Two Sentences	Easy
890	Find and Replace Pattern	Medium
901	Online Stock Span	Medium
905	Sort Array By Parity	Easy
912	Sort an Array	Medium
914	X of a Kind in a Deck of Cards	Medium
916	Word Subsets	Medium
922	Sort Array By Parity II	Easy
925	Long Pressed Name	Easy
926	Flip String to Monotone Increasing	Medium
929	Unique Email Addresses	Easy
933	Number of Recent Calls	Easy
966	Vowel Spellchecker	Medium
970	Powerful Integers	Easy
976	Largest Perimeter Triangle	Easy
977	Squares of a Sorted Array	Easy
985	Sum of Even Numbers After Queries	Easy
989	Add to Array-Form of Integer	Easy
994	Rotting Oranges	Medium
997	Find the Town Judge	Easy
1002	Find Common Characters	Easy
1004	Max Consecutive Ones III	Medium
1005	Maximize Sum Of Array After K Negations	Easy
1009	Complement of Base 10 Integer	Easy
1010	Pairs of Songs With Total Durations Divisible by 60	Medium
1022	Sum of Root To Leaf Binary Numbers	Easy
1023	Camelcase Matching	Medium
1037	Valid Boomerang	Easy
1041	Robot Bounded In Circle	Medium
1047	Remove All Adjacent Duplicates In String	Easy
1051	Height Checker	Easy
1071	Greatest Common Divisor of Strings	Easy
1081	Smallest Subsequence of Distinct Characters	Medium
1103	Distribute Candies to People	Easy
1108	Defanging an IP Address	Easy
1122	Relative Sort Array	Easy
1189	Maximum Number of Balloons	Easy
1200	Minimum Absolute Difference	Easy
1206	Design Skiplist	Hard
1207	Unique Number of Occurrences	Easy
1208	Get Equal Substrings Within Budget	Medium
1217	Minimum Cost to Move Chips to The Same Position	Easy
1232	Check If It Is a Straight Line	Easy
1233	Remove Sub-Folders from the Filesystem	Medium
1249	Minimum Remove to Make Valid Parentheses	Medium
1252	Cells with Odd Values in a Matrix	Easy
1287	Element Appearing More Than 25% In Sorted Array	Easy
1290	Convert Binary Number in a Linked List to Integer	Easy
1291	Sequential Digits	Medium
1292	Maximum Side Length of a Square with Sum Less than or Equal to Threshold	Medium
1295	Find Numbers with Even Number of Digits	Easy
1296	Divide Array in Sets of K Consecutive Numbers	Medium
1297	Maximum Number of Occurrences of a Substring	Medium
1304	Find N Unique Integers Sum up to Zero	Easy
1309	Decrypt String from Alphabet to Integer Mapping	Easy
1313	Decompress Run-Length Encoded List	Easy
1317	Convert Integer to the Sum of Two No-Zero Integers	Easy
1318	Minimum Flips to Make a OR b Equal to c	Medium
1323	Maximum 69 Number	Easy
1324	Print Words Vertically	Medium
1331	Rank Transform of an Array	Easy
1332	Remove Palindromic Subsequences	Easy
1333	Filter Restaurants by Vegan-Friendly, Price and Distance	Medium
1342	Number of Steps to Reduce a Number to Zero	Easy
1351	Count Negative Numbers in a Sorted Matrix	Easy
1356	Sort Integers by The Number of 1 Bits	Easy
1360	Number of Days Between Two Dates	Easy
1365	How Many Numbers Are Smaller Than the Current Number	Easy
1368	Minimum Cost to Make at Least One Valid Path in a Grid	Hard
1374	Generate a String With Characters That Have Odd Counts	Easy
1380	Lucky Numbers in a Matrix	Easy
1389	Create Target Array in the Given Order	Easy
1400	Construct K Palindrome Strings	Medium
1402	Reducing Dishes	Hard
1408	String Matching in an Array	Easy
1410	HTML Entity Parser	Medium
1431	Kids With the Greatest Number of Candies	Easy
1436	Destination City	Easy
1437	Check If All 1's Are at Least Length K Places Away	Easy
1443	Minimum Time to Collect All Apples in a Tree	Medium
1446	Consecutive Characters	Easy
1447	Simplified Fractions	Medium
1450	Number of Students Doing Homework at a Given Time	Easy
1451	Rearrange Words in a Sentence	Medium
1455	Check If a Word Occurs As a Prefix of Any Word in a Sentence	Easy
1456	Maximum Number of Vowels in a Substring of Given Length	Medium
1460	Make Two Arrays Equal by Reversing Sub-arrays	Easy
1464	Maximum Product of Two Elements in an Array	Easy
1466	Reorder Routes to Make All Paths Lead to the City Zero	Medium
1470	Shuffle the Array	Easy
1472	Design Browser History	Medium
1475	Final Prices With a Special Discount in a Shop	Easy
1480	Running Sum of 1d Array	Easy
1481	Least Number of Unique Integers after K Removals	Medium
1486	XOR Operation in an Array	Easy
1491	Average Salary Excluding the Minimum and Maximum Salary	Easy
1492	The kth Factor of n	Medium
1493	Longest Subarray of 1's After Deleting One Element	Medium
1496	Path Crossing	Easy
1502	Can Make Arithmetic Progression From Sequence	Easy
1507	Reformat Date	Easy
1512	Number of Good Pairs	Easy
1519	Number of Nodes in the Sub-Tree With the Same Label	Medium
1528	Shuffle String	Easy
1550	Three Consecutive Odds	Easy
1551	Minimum Operations to Make Array Equal	Medium
1566	Detect Pattern of Length M Repeated K or More Times	Easy
1576	Replace All ?'s to Avoid Consecutive Repeating Characters	Medium
1598	Crawler Log Folder	Easy
1657	Determine if Two Strings Are Close	Medium
1668	Maximum Repeating Substring	Easy
1669	Merge In Between Linked Lists	Medium
1672	Richest Customer Wealth	Easy
1679	Max Number of K-Sum Pairs	Medium
1716	Calculate Money in Leetcode Bank	Easy
1732	Find the Highest Altitude	Easy
1748	Sum of Unique Elements	Easy
1765	Map of Highest Peak	Medium
1768	Merge Strings Alternately	Easy
1780	Check if Number is a Sum of Powers of Three	Medium
1791	Find Center of Star Graph	Easy
1812	Determine Color of a Chessboard Square	Easy
1817	Finding the Users Active Minutes	Medium
1832	Check if the Sentence Is Pangram	Easy
1833	Maximum Ice Cream Bars	Medium
1880	Check if Word Equals Summation of Two Words	Easy
1886	Determine Whether Matrix Can Be Obtained By Rotation	Easy
1920	Build Array from Permutation	Easy
1929	Concatenation of Array	Easy
1935	Maximum Number of Words You Can Type	Easy
1996	The Number of Weak Characters in the Game	Medium
2000	Reverse Prefix of Word	Easy
2011	Final Value of Variable After Performing Operations	Easy
2016	Maximum Difference Between Increasing Elements	Easy
2017	Grid Game	Medium
2027	Minimum Moves to Convert String	Easy
2037	Minimum Number of Moves to Seat Everyone	Easy
2047	Number of Valid Words in a Sentence	Easy
2053	Kth Distinct String in an Array	Medium
2085	Count Common Words With One Occurrence	Easy
2095	Delete the Middle Node of a Linked List	Medium
2099	Find Subsequence of Length K With the Largest Sum	Medium
2114	Maximum Number of Words Found in Sentences	Easy
2116	Check if a Parentheses String Can Be Valid	Medium
2129	Capitalize the Title	Easy
2130	Maximum Twin Sum of a Linked List	Medium
2154	Keep Multiplying Found Values by Two	Easy
2185	Counting Words With a Given Prefix	Easy
2215	Find the Difference of Two Arrays	Easy
2235	Add Two Integers	Easy
2244	Minimum Rounds to Complete All Tasks	Medium
2352	Equal Row and Column Pairs	Medium
2390	Removing Stars From a String	Medium
2396	Strictly Palindromic Number	Medium
2413	Smallest Even Multiple	Easy
2425	Bitwise XOR of All Pairings	Medium
2427	Number of Common Factors	Easy
2429	Minimize XOR	Medium
2469	Convert the Temperature	Easy
2482	Difference Between Ones and Zeros in Row and Column	Medium
2490	Circular Sentence	Easy
2529	Maximum Count of Positive Integer and Negative Integer	Easy
2535	Difference Between Element Sum and Digit Sum of an Array	Easy
2618	Check if Object Instance of Class	Medium
2619	Array Prototype Last	Easy
2620	Counter	Easy
2621	Sleep	Easy
2622	Cache With Time Limit	Medium
2623	Memoize	Medium
2625	Flatten Deeply Nested Array	Medium
2626	Array Reduce Transformation	Easy
2627	Debounce	Medium
2629	Function Composition	Easy
2630	Memoize II	Hard
2631	Group By	Medium
2634	Filter Elements from Array	Easy
2635	Apply Transform Over Each Element in Array	Easy
2637	Promise Time Limit	Medium
2648	Generate Fibonacci Sequence	Easy
2649	Nested Array Generator	Medium
2650	Design Cancellable Function	Hard
2657	Find the Prefix Common Array of Two Arrays	Medium
2661	First Completely Painted Row or Column	Medium
2665	Counter II	Easy
2666	Allow One Function Call	Easy
2667	Create Hello World Function	Easy
2677	Chunk Array	Easy
2683	Neighboring Bitwise XOR	Medium
2693	Call Function with Custom Context	Medium
2695	Array Wrapper	Easy
2703	Return Length of Arguments Passed	Easy
2704	To Be Or Not To Be	Easy
2705	Compact Object	Medium
2715	Timeout Cancellation	Easy
2721	Execute Asynchronous Functions in Parallel	Medium
2722	Join Two Arrays by ID	Medium
2723	Add Two Promises	Easy
2724	Sort By	Easy
3042	Count Prefix and Suffix Pairs I	Easy
3110	Score of a String	Easy
3223	Minimum Length of String After Operations	Medium
3392	Count Subarrays of Length Three With a Condition	Easy
3396	Minimum Number of Operations to Make Elements in Array Distinct	Easy
3397	Maximum Number of Distinct Elements After Operations	Medium
3402	Minimum Operations to Make Columns Strictly Increasing	Easy

License

MIT License

Copyright (c) 2019-2025 Josh Crozier