LeetCode

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Question List

#	Title	Difficulty	Solution
1	Two Sum	$\color{green}{\textsf{Easy}}$	Go
2	Add Two Numbers	$\color{orange}{\textsf{Medium}}$	Go
3	Longest Substring Without Repeating Characters	$\color{orange}{\textsf{Medium}}$	Go
9	Palindrome Number	$\color{green}{\textsf{Easy}}$	Go
11	Container With Most Water	$\color{orange}{\textsf{Medium}}$	Go
13	Roman to Integer	$\color{green}{\textsf{Easy}}$
14	Longest Common Prefix	$\color{green}{\textsf{Easy}}$
15	3Sum	$\color{orange}{\textsf{Medium}}$	Go
16	3Sum Closest	$\color{orange}{\textsf{Medium}}$	Go
17	Letter Combinations of a Phone Number	$\color{orange}{\textsf{Medium}}$	Go
18	4Sum	$\color{orange}{\textsf{Medium}}$	Go
20	Valid Parentheses	$\color{green}{\textsf{Easy}}$	Go
21	Merge Two Sorted Lists	$\color{green}{\textsf{Easy}}$
26	Remove Duplicates from Sorted Array	$\color{green}{\textsf{Easy}}$	Go
27	Remove Element	$\color{green}{\textsf{Easy}}$	Go
28	Find the Index of the First Occurrence in a String	$\color{green}{\textsf{Easy}}$	Go
31	Next Permutation	$\color{orange}{\textsf{Medium}}$	Go
35	Search Insert Position	$\color{green}{\textsf{Easy}}$	Go
46	Permutations	$\color{orange}{\textsf{Medium}}$	Go
48	Rotate Image	$\color{orange}{\textsf{Medium}}$	Go
52	N-Queens II	$\color{red}{\textsf{Hard}}$	Go
53	Maximum Subarray	$\color{orange}{\textsf{Medium}}$
54	Spiral Matrix	$\color{orange}{\textsf{Medium}}$	Go
58	Length of Last Word	$\color{green}{\textsf{Easy}}$
61	Rotate List	$\color{orange}{\textsf{Medium}}$	Go
66	Plus One	$\color{green}{\textsf{Easy}}$
67	Add Binary	$\color{green}{\textsf{Easy}}$
69	Sqrt(x)	$\color{green}{\textsf{Easy}}$
70	Climbing Stairs	$\color{green}{\textsf{Easy}}$
73	Set Matrix Zeroes	$\color{orange}{\textsf{Medium}}$	Go
75	Sort Colors	$\color{orange}{\textsf{Medium}}$	Go
83	Remove Duplicates from Sorted List	$\color{green}{\textsf{Easy}}$
88	Merge Sorted Array	$\color{green}{\textsf{Easy}}$	Go
94	Binary Tree Inorder Traversal	$\color{green}{\textsf{Easy}}$
98	Validate Binary Search Tree	$\color{orange}{\textsf{Medium}}$	Go
100	Same Tree	$\color{green}{\textsf{Easy}}$	GO
101	Symmetric Tree	$\color{green}{\textsf{Easy}}$
102	Binary Tree Level Order Traversal	$\color{orange}{\textsf{Medium}}$	Go
104	Maximum Depth of Binary Tree	$\color{green}{\textsf{Easy}}$	Go
105	Construct Binary Tree from Preorder and Inorder Traversal	$\color{orange}{\textsf{Medium}}$	Go
110	Balanced Binary Tree	$\color{green}{\textsf{Easy}}$
121	Best Time to Buy and Sell Stock	$\color{green}{\textsf{Easy}}$
125	Valid Palindrome	$\color{green}{\textsf{Easy}}$	Go
133	133.clone_graph	$\color{orange}{\textsf{Medium}}$	Go
136	Single Number	$\color{green}{\textsf{Easy}}$	Go
141	Linked List Cycle	$\color{green}{\textsf{Easy}}$	Go
142	Linked List Cycle II	$\color{orange}{\textsf{Medium}}$	Go
143	Reorder List	$\color{orange}{\textsf{Medium}}$	Go
144	Binary Tree Preorder Traversal	$\color{green}{\textsf{Easy}}$
145	Binary Tree Postorder Traversal	$\color{green}{\textsf{Easy}}$
151	Reverse Words in a String	$\color{orange}{\textsf{Medium}}$	Go
159	Longest Substring with At Most Two Distinct Characters 🔒	$\color{orange}{\textsf{Medium}}$	Go
160	Intersection of Two Linked Lists	$\color{green}{\textsf{Easy}}$	Go
162	Find Peak Element	$\color{orange}{\textsf{Medium}}$	Go
167	Two Sum II - Input Array Is Sorted	$\color{orange}{\textsf{Medium}}$	Go
170	Two Sum III - Data structure design 🔒	$\color{green}{\textsf{Easy}}$	Go
171	Excel Sheet Column Number	$\color{green}{\textsf{Easy}}$	Go
175	Combine Two Tables	$\color{green}{\textsf{Easy}}$
176	Second Highest Salary	$\color{orange}{\textsf{Medium}}$	MySQL
180	Consecutive Numbers	$\color{orange}{\textsf{Medium}}$	MySQL
185	Department Top Three Salaries	$\color{red}{\textsf{Hard}}$	MySQL
186	Reverse Words in a String II 🔒	$\color{orange}{\textsf{Medium}}$	Go
190	Reverse Bits	$\color{green}{\textsf{Easy}}$	Go
191	Number of 1 Bits	$\color{green}{\textsf{Easy}}$	Go
196	Delete Duplicate Emails	$\color{green}{\textsf{Easy}}$	MySQL
197	Rising Temperature	$\color{green}{\textsf{Easy}}$	MySQL
199	Binary Tree Right Side View	$\color{orange}{\textsf{Medium}}$	Go
202	Happy Number	$\color{green}{\textsf{Easy}}$	Go
206	Reverse Linked List	$\color{green}{\textsf{Easy}}$	Go
208	Implement Trie (Prefix Tree)	$\color{orange}{\textsf{Medium}}$	Go
215	Kth Largest Element in an Array	$\color{orange}{\textsf{Medium}}$	Go
216	Combination Sum III	$\color{orange}{\textsf{Medium}}$	Go
217	Contains Duplicate	$\color{green}{\textsf{Easy}}$	Go
219	Contains Duplicate II	$\color{green}{\textsf{Easy}}$	Go
222	Count Complete Tree Nodes	$\color{green}{\textsf{Easy}}$	Go
225	Implement Stack using Queues	$\color{green}{\textsf{Easy}}$
226	Invert Binary Tree	$\color{green}{\textsf{Easy}}$	Go
230	Kth Smallest Element in a BST	$\color{orange}{\textsf{Medium}}$	Go
234	Palindrome Linked List	$\color{green}{\textsf{Easy}}$	Go
236	Lowest Common Ancestor of a Binary tree	$\color{orange}{\textsf{Medium}}$	Go
238	Product of Array Except Self	$\color{orange}{\textsf{Medium}}$	Go
242	Valid Anagram	$\color{green}{\textsf{Easy}}$	Go
246	Strobogrammatic Number 🔒	$\color{green}{\textsf{Easy}}$	Go
253	Meeting Rooms II 🔒	$\color{orange}{\textsf{Medium}}$	Go
278	First Bad Version	$\color{green}{\textsf{Easy}}$
283	Move Zeroes	$\color{green}{\textsf{Easy}}$	Go
328	Odd Even Linked List	$\color{orange}{\textsf{Medium}}$	Go
334	Increasing Triplet Subsequence	$\color{orange}{\textsf{Medium}}$	Go
338	Counting Bits	$\color{green}{\textsf{Easy}}$	Go
340	Longest Substring with At Most K Distinct Characters 🔒	$\color{orange}{\textsf{Medium}}$	Go
344	Reverse String	$\color{green}{\textsf{Easy}}$	Go
345	Reverse Vowels of a String	$\color{green}{\textsf{Easy}}$	Go
347	Top K Frequent Elements	$\color{orange}{\textsf{Medium}}$	Go
349	Intersection of Two Arrays	$\color{green}{\textsf{Easy}}$	Go
350	Intersection of Two Arrays II	$\color{green}{\textsf{Easy}}$	Go
371	Sum of Two Integers	$\color{orange}{\textsf{Medium}}$	Go
374	Guess Number Higher or Lower	$\color{green}{\textsf{Easy}}$	Go
392	Is Subsequence	$\color{green}{\textsf{Easy}}$	Go
394	Decode String	$\color{orange}{\textsf{Medium}}$	Go
395	Longest Substring with At Least K Repeatin	$\color{orange}{\textsf{Medium}}$	Go
399	Evaluate Division	$\color{orange}{\textsf{Medium}}$	Go
408	Valid Word Abbreviation 🔒	$\color{green}{\textsf{Easy}}$	Go
412	Fizz Buzz	$\color{green}{\textsf{Easy}}$	Go
415	Add Strings	$\color{green}{\textsf{Easy}}$	Go
437	Path Sum III	$\color{orange}{\textsf{Medium}}$	Go
443	String Compression	$\color{orange}{\textsf{Medium}}$	Go
450	Delete Node in a BST	$\color{orange}{\textsf{Medium}}$	go
455	Assign Cookies	$\color{green}{\textsf{Easy}}$	Go
457	Circular Array Loop	$\color{orange}{\textsf{Medium}}$	Go
489	Robot Room Cleaner 🔒	$\color{red}{\textsf{Hard}}$	Go
490	The Maze 🔒	$\color{orange}{\textsf{Medium}}$	Go
496	Next Greater Element I	$\color{green}{\textsf{Easy}}$	Go
541	Reverse String II	$\color{green}{\textsf{Easy}}$	Go
547	Number of Provinces	$\color{orange}{\textsf{Medium}}$	Go
550	Game Play Analysis IV	$\color{orange}{\textsf{Medium}}$	MySQL
557	Reverse Words in a String III	$\color{green}{\textsf{Easy}}$	Go
570	Managers with at Least 5 Direct Reports	$\color{orange}{\textsf{Medium}}$	MySQL
577	Employee Bonus	$\color{green}{\textsf{Easy}}$	MySQL
584	Find Customer Referee	$\color{green}{\textsf{Easy}}$	MySQL
585	Investments in 2016	$\color{orange}{\textsf{Medium}}$	MySQL
595	Big Countries	$\color{green}{\textsf{Easy}}$	Python3 MySQL
596	Classes More Than 5 Students	$\color{green}{\textsf{Easy}}$	MySQL
602	Friend Requests II: Who Has the Most Friends	$\color{orange}{\textsf{Medium}}$	MySQL
605	Can Place Flowers	$\color{green}{\textsf{Easy}}$	Go
610	Triangle Judgement	$\color{green}{\textsf{Easy}}$	MySQL
619	Biggest Single Number	$\color{green}{\textsf{Easy}}$	MySQL
620	Not Boring Movies	$\color{green}{\textsf{Easy}}$	MySQL
624	Maximum Distance in Arrays 🔒	$\color{orange}{\textsf{Medium}}$	Go
626	Exchange Seats	$\color{orange}{\textsf{Medium}}$	MySQL
643	Maximum Average Subarray I	$\color{green}{\textsf{Easy}}$	Go
649	Dota2 Senate	$\color{orange}{\textsf{Medium}}$	Go
653	Two Sum IV - Input is a BST	$\color{green}{\textsf{Easy}}$	Go
680	Valid Palindrome II	$\color{green}{\textsf{Easy}}$	Go
682	Baseball Game	$\color{green}{\textsf{Easy}}$	Go
696	Count Binary Substrings	$\color{green}{\textsf{Easy}}$	Go
700	Search in a Binary Search Tree	$\color{green}{\textsf{Easy}}$	Go
713	Subarray Product Less Than K	$\color{orange}{\textsf{Medium}}$	Go
724	Find Pivot Index	$\color{green}{\textsf{Easy}}$	Go
735	Asteroid Collision	$\color{orange}{\textsf{Medium}}$	Go
821	Shortest Distance to a Character	$\color{green}{\textsf{Easy}}$	Go
832	Flipping an Image	$\color{green}{\textsf{Easy}}$	Go
841	Keys and Rooms	$\color{orange}{\textsf{Medium}}$	Go
844	Backspace String Compare	$\color{green}{\textsf{Easy}}$	Go
872	Leaf-Similar Trees	$\color{green}{\textsf{Easy}}$	Go
875	Koko Eating Bananas	$\color{orange}{\textsf{Medium}}$	Go
876	Middle of the Linked List	$\color{green}{\textsf{Easy}}$	Go
897	Increasing Order Search Tree	$\color{green}{\textsf{Easy}}$
905	Sort Array By Parity	$\color{green}{\textsf{Easy}}$	Go
917	Reverse Only Letters	$\color{green}{\textsf{Easy}}$	Go
922	Sort Array By Parity II	$\color{green}{\textsf{Easy}}$	Go
925	Long Pressed Name	$\color{green}{\textsf{Easy}}$	Go
933	Number of Recent Calls	$\color{green}{\textsf{Easy}}$
942	DI String Match	$\color{green}{\textsf{Easy}}$	Go
977	Squares of a Sorted Array	$\color{green}{\textsf{Easy}}$	Go
994	Rotting Oranges	$\color{orange}{\textsf{Medium}}$	Go
1002	Find Common Characters	$\color{green}{\textsf{Easy}}$	Go
1004	Max Consecutive Ones III	$\color{orange}{\textsf{Medium}}$	Go
1021	Remove Outermost Parentheses	$\color{green}{\textsf{Easy}}$
1045	Customers Who Bought All Products	$\color{orange}{\textsf{Medium}}$	MySQL
1047	Remove All Adjacent Duplicates In String	$\color{green}{\textsf{Easy}}$	Go
1056	Confusing Number 🔒	$\color{green}{\textsf{Easy}}$	Go
1068	Product Sales Analysis I	$\color{green}{\textsf{Easy}}$	MySQL
1070	Product Sales Analysis III	$\color{orange}{\textsf{Medium}}$	MySQL
1071	Greatest Common Divisor of Strings	$\color{green}{\textsf{Easy}}$	Go
1075	Project Employees I	$\color{green}{\textsf{Easy}}$	MySQL
1088	Confusing Number II 🔒	$\color{red}{\textsf{Hard}}$	Go
1089	Duplicate Zeros	$\color{green}{\textsf{Easy}}$	Go
1099	Two Sum Less Than K 🔒	$\color{green}{\textsf{Easy}}$	Go
1120	Maximum Average Subtree 🔒	$\color{orange}{\textsf{Medium}}$	Go
1137	N-th Tribonacci Number	$\color{green}{\textsf{Easy}}$	Go
1141	User Activity for the Past 30 Days I	$\color{green}{\textsf{Easy}}$	MySQL
1148	Article Views I	$\color{green}{\textsf{Easy}}$	MySQL
1160	Find Words That Can Be Formed by Characters	$\color{green}{\textsf{Easy}}$	Go
1161	Maximum Level Sum of a Binary Tree	$\color{orange}{\textsf{Medium}}$	Go
1164	Product Price at a Given Date	$\color{orange}{\textsf{Medium}}$	MySQL
1174	Immediate Food Delivery II	$\color{orange}{\textsf{Medium}}$	MySQL
1176	Diet Plan Performance 🔒	$\color{green}{\textsf{Easy}}$	Go
1193	Monthly Transactions I	$\color{orange}{\textsf{Medium}}$	MySQL
1204	Last Person to Fit in the Bus	$\color{orange}{\textsf{Medium}}$	MySQL
1207	Unique Number of Occurrences	$\color{green}{\textsf{Easy}}$	Go
1211	Queries Quality and Percentage	$\color{green}{\textsf{Easy}}$	MySQL
1251	Average Selling Price	$\color{green}{\textsf{Easy}}$	MySQL
1268	Search Suggestions System	$\color{orange}{\textsf{Medium}}$	Go
1280	Students and Examinations	$\color{green}{\textsf{Easy}}$	MySQL
1321	Restaurant Growth	$\color{orange}{\textsf{Medium}}$	MySQL
1327	List the Products Ordered in a Period	$\color{green}{\textsf{Easy}}$	MySQL
1341	Movie Rating	$\color{orange}{\textsf{Medium}}$	MySQL
1372	Longest ZigZag Path in a Binary Tree	$\color{orange}{\textsf{Medium}}$	Go
1378	Replace Employee ID With The Unique Identifier	$\color{green}{\textsf{Easy}}$	MySQL
1385	Find the Distance Value Between Two Arrays	$\color{green}{\textsf{Easy}}$	Go
1403	Minimum Subsequence in Non-Increasing	$\color{green}{\textsf{Easy}}$
1431	Kids With the Greatest Number of Candies	$\color{green}{\textsf{Easy}}$	Go
1448	Count Good Nodes in Binary Tree	$\color{orange}{\textsf{Medium}}$	Go
1456	Maximum Number of Vowels in a Substring	$\color{orange}{\textsf{Medium}}$	Go
1466	Reorder Routes to Make All Paths Lead to the City Zero	$\color{orange}{\textsf{Medium}}$	Go
1484	Group Sold Products By The Date	$\color{green}{\textsf{Easy}}$	MySQL
1493	Longest Subarray of 1's After Deleting One Element	$\color{orange}{\textsf{Medium}}$	Go
1527	Patients With a Condition	$\color{green}{\textsf{Easy}}$	MySQL
1544	Make The String Great	$\color{green}{\textsf{Easy}}$	Go
1561	Maximum Number of Coins You Can Get	$\color{orange}{\textsf{Medium}}$	Go
1581	Customer Who Visited but Did Not Make Any Transactions	$\color{green}{\textsf{Easy}}$	MySQL
1633	Percentage of Users Attended a Contest	$\color{green}{\textsf{Easy}}$	MySQL
1661	Average Time of Process per Machine	$\color{green}{\textsf{Easy}}$	MySQL
1657	Determine if Two Strings Are Close	$\color{orange}{\textsf{Medium}}$	Go
1662	Check If Two String Arrays are Equivalent	$\color{green}{\textsf{Easy}}$	Go
1667	Fix Names in a Table	$\color{green}{\textsf{Easy}}$	MySQL
1679	Max Number of K-Sum Pairs	$\color{orange}{\textsf{Medium}}$	Go
1683	Invalid Tweets	$\color{green}{\textsf{Easy}}$	MySQL
1685	Sum of Absolute Differences in a Sorted	$\color{orange}{\textsf{Medium}}$	Go
1688	Count of Matches in Tournament	$\color{green}{\textsf{Easy}}$	Go
1729	Find Followers Count	$\color{green}{\textsf{Easy}}$	MySQL
1731	The Number of Employees Which Report to Each Employee	$\color{green}{\textsf{Easy}}$	MySQL
1732	Find the Highest Altitude	$\color{green}{\textsf{Easy}}$	Go
1757	Recyclable and Low Fat Products	$\color{green}{\textsf{Easy}}$	Python3 MySQL
1768	Merge Strings Alternately	$\color{green}{\textsf{Easy}}$	Go
1789	Primary Department for Each Employee	$\color{green}{\textsf{Easy}}$	MySQL
1791	Find Center of Star Graph	$\color{green}{\textsf{Easy}}$	Go
1826	Faulty Sensor 🔒	$\color{green}{\textsf{Easy}}$	Go
1907	Count Salary Categories	$\color{orange}{\textsf{Medium}}$	MySQL
1926	Nearest Exit from Entrance in Maze	$\color{orange}{\textsf{Medium}}$	Go
1934	Confirmation Rate	$\color{orange}{\textsf{Medium}}$	MySQL
1971	Find if Path Exists in Graph	$\color{green}{\textsf{Easy}}$	Go
1978	Employees Whose Manager Left the Company	$\color{green}{\textsf{Easy}}$	MySQL
2000	Reverse Prefix of Word	$\color{green}{\textsf{Easy}}$	Go
2095	Delete the Middle Node of a Linked List	$\color{orange}{\textsf{Medium}}$	Go
2121	Intervals Between Identical Elements	$\color{orange}{\textsf{Medium}}$	Go
2130	Maximum Twin Sum of a Linked List	$\color{orange}{\textsf{Medium}}$	Go
2164	Sort Even and Odd Indices Independently	$\color{green}{\textsf{Easy}}$	Go
2215	Find the Difference of Two Arrays	$\color{green}{\textsf{Easy}}$	Go
2300	Successful Pairs of Spells and Potions	$\color{orange}{\textsf{Medium}}$	Go
2336	Smallest Number in Infinite Set	$\color{orange}{\textsf{Medium}}$	Go
2352	Equal Row and Column Pairs	$\color{orange}{\textsf{Medium}}$	Go
2356	Number of Unique Subjects Taught by Each Teacher	$\color{green}{\textsf{Easy}}$	MySQL
2367	Number of Arithmetic Triplets	$\color{green}{\textsf{Easy}}$	Go
2390	Removing Stars From a String	$\color{orange}{\textsf{Medium}}$	Go
2441	Largest Positive Integer That Exists With Its Negative	$\color{green}{\textsf{Easy}}$	Go
2462	Total Cost to Hire K Workers	$\color{orange}{\textsf{Medium}}$	Go
2542	Maximum Subsequence Score	$\color{orange}{\textsf{Medium}}$	Go
2562	Find the Array Concatenation Value	$\color{green}{\textsf{Easy}}$	Go
2570	Merge Two 2D Arrays by Summing Values	$\color{green}{\textsf{Easy}}$	Go
2706	Buy Two Chocolates	$\color{green}{\textsf{Easy}}$	Go
2824	Count Pairs Whose Sum is Less than Target	$\color{green}{\textsf{Easy}}$	Go