LeetCode Solutions Archive

Automated synchronization of solved LeetCode problems with original completion dates.

📊 Progress Overview

Total Solved: 208
🟢 Easy: 115
🟡 Medium: 86
🔴 Hard: 7

🏷️ Topic Summary

Topic	Solved Count
`Database`	83
`Array`	75
`Hash Table`	33
`String`	32
`Two Pointers`	31
`Math`	25
`Sorting`	24
`Sliding Window`	14
`Binary Search`	14
`Simulation`	12
`Prefix Sum`	10
`Linked List`	8
`Dynamic Programming`	7
`Bit Manipulation`	5
`Counting`	5
`Number Theory`	4
`Floyd's Cycle Finding Algorithm`	4
`Divide and Conquer`	4
`Recursion`	3
`Greedy`	2
`Matrix`	2
`Pigeonhole Principle`	2
`Z Algorithm`	2
`Boyer–Moore String-Search Algorithm`	2
`Boyer–Moore Majority Vote Algorithm`	2
`Counting Sort`	2
`Heap (Priority Queue)`	2
`Quicksort`	2
`Enumeration`	2
`Euclidean Algorithm`	1
`Greatest Common Divisor`	1
`String Matching`	1
`Knuth–Morris–Pratt Algorithm`	1
`Trie`	1
`Union-Find`	1
`Bucket Sort`	1
`Radix Sort`	1
`Queue`	1
`Monotonic Queue`	1
`Rolling Hash`	1
`Hash Function`	1
`Bubble Sort`	1
`Minimax`	1
`Game Theory`	1
`Zero-Sum Game`	1
`Stack`	1
`Bracket Sequences`	1

📜 Solutions Index

#	Problem	Difficulty	Topics	Solution
15	3Sum	Medium	`Array`, `Two Pointers`, `Sorting`	3sum/Solution.py
16	3Sum Closest	Medium	`Array`, `Two Pointers`, `Sorting`	3sum-closest/Solution.py
18	4Sum	Medium	`Array`, `Two Pointers`, `Sorting`	4sum/Solution.py
1136	Actors and Directors Who Cooperated At Least Three Times	Easy	`Database`	actors-and-directors-who-cooperated-at-least-three-times/Solution.sql
67	Add Binary	Easy	`Math`, `String`, `Bit Manipulation`, `Simulation`	add-binary/Solution.py
258	Add Digits	Easy	`Math`, `Simulation`, `Number Theory`	add-digits/Solution.py
2	Add Two Numbers	Medium	`Linked List`, `Math`, `Recursion`	add-two-numbers/Solution.py
1446	Angle Between Hands of a Clock	Medium	`Math`	angle-between-hands-of-a-clock/Solution.py
1258	Article Views I	Easy	`Database`	article-views-i/Solution.sql
1390	Average Selling Price	Easy	`Database`	average-selling-price/Solution.sql
1801	Average Time of Process per Machine	Easy	`Database`	average-time-of-process-per-machine/Solution.sql
1734	Bank Account Summary II	Easy	`Database`	bank-account-summary-ii/Solution.sql
121	Best Time to Buy and Sell Stock	Easy	`Array`, `Dynamic Programming`	best-time-to-buy-and-sell-stock/Solution.py
595	Big Countries	Easy	`Database`	big-countries/Solution.sql
619	Biggest Single Number	Easy	`Database`	biggest-single-number/Solution.sql
299	Bulls and Cows	Medium	`Hash Table`, `String`, `Counting`	bulls-and-cows/Solution.py
2024	Calculate Special Bonus	Easy	`Database`	calculate-special-bonus/Solution.sql
1523	Capital Gain/Loss	Medium	`Database`	capital-gainloss/Solution.sql
3918	Check Divisibility by Digit Sum and Product	Easy	`Math`	check-divisibility-by-digit-sum-and-product/Solution.py
2377	Check if Number Has Equal Digit Count and Digit Value	Easy	`Hash Table`, `String`, `Counting`	check-if-number-has-equal-digit-count-and-digit-value/Solution.py
596	Classes With at Least 5 Students	Easy	`Database`	classes-with-at-least-5-students/Solution.sql
175	Combine Two Tables	Easy	`Database`	combine-two-tables/Solution.sql
4058	Compute Alternating Sum	Easy	`Array`, `Simulation`	compute-alternating-sum/Solution.py
2058	Concatenation of Array	Easy	`Array`, `Simulation`	concatenation-of-array/Solution.py
2087	Confirmation Rate	Medium	`Database`	confirmation-rate/Solution.sql
180	Consecutive Numbers	Medium	`Database`	consecutive-numbers/Solution.sql
4256	Construct Uniform Parity Array I	Easy	`Array`, `Math`	construct-uniform-parity-array-i/Solution.py
11	Container With Most Water	Medium	`Array`, `Two Pointers`, `Greedy`	container-with-most-water/Solution.py
217	Contains Duplicate	Easy	`Array`, `Hash Table`, `Sorting`	contains-duplicate/Solution.py
219	Contains Duplicate II	Easy	`Array`, `Hash Table`, `Sliding Window`	contains-duplicate-ii/Solution.py
4245	Count Commas in Range	Easy	`Math`	count-commas-in-range/Solution.py
4248	Count Commas in Range II	Medium	`Math`	count-commas-in-range-ii/Solution.py
2057	Count Salary Categories	Medium	`Database`	count-salary-categories/Solution.sql
3338	Count Submatrices with Top-Left Element and Sum Less Than k	Medium	`Array`, `Matrix`, `Prefix Sum`	count-submatrices-with-top-left-element-and-sum-less-than-k/Solution.py
3405	Count the Number of Special Characters II	Medium	`Hash Table`, `String`	count-the-number-of-special-characters-ii/Solution.py
586	Customer Placing the Largest Number of Orders	Easy	`Database`	customer-placing-the-largest-number-of-orders/Solution.sql
1724	Customer Who Visited but Did Not Make Any Transactions	Easy	`Database`	customer-who-visited-but-did-not-make-any-transactions/Solution.sql
1135	Customers Who Bought All Products	Medium	`Database`	customers-who-bought-all-products/Solution.sql
183	Customers Who Never Order	Easy	`Database`	customers-who-never-order/Solution.sql
1837	Daily Leads and Partners	Easy	`Database`	daily-leads-and-partners/Solution.sql
196	Delete Duplicate Emails	Easy	`Database`	delete-duplicate-emails/Solution.sql
184	Department Highest Salary	Medium	`Database`	department-highest-salary/Solution.sql
185	Department Top Three Salaries	Hard	`Database`	department-top-three-salaries/Solution.sql
3347	Distribute Elements Into Two Arrays I	Easy	`Array`, `Simulation`	distribute-elements-into-two-arrays-i/Solution.py
3816	DNA Pattern Recognition	Medium	`Database`	dna-pattern-recognition/Solution.sql
182	Duplicate Emails	Easy	`Database`	duplicate-emails/Solution.sql
577	Employee Bonus	Easy	`Database`	employee-bonus/Solution.sql
181	Employees Earning More Than Their Managers	Easy	`Database`	employees-earning-more-than-their-managers/Solution.sql
2127	Employees Whose Manager Left the Company	Easy	`Database`	employees-whose-manager-left-the-company/Solution.sql
2110	Employees With Missing Information	Easy	`Database`	employees-with-missing-information/Solution.sql
626	Exchange Seats	Medium	`Database`	exchange-seats/Solution.sql
438	Find All Anagrams in a String	Medium	`Hash Table`, `String`, `Sliding Window`	find-all-anagrams-in-a-string/Solution.py
3910	Find Books with No Available Copies	Easy	`Database`	find-books-with-no-available-copies/Solution.sql
3891	Find Category Recommendation Pairs	Hard	`Database`	find-category-recommendation-pairs/Solution.sql
3932	Find COVID Recovery Patients	Medium	`Database`	find-covid-recovery-patients/Solution.sql
584	Find Customer Referee	Easy	`Database`	find-customer-referee/Solution.sql
34	Find First and Last Position of Element in Sorted Array	Medium	`Array`, `Binary Search`	find-first-and-last-position-of-element-in-sorted-array/Solution.py
1877	Find Followers Count	Easy	`Database`	find-followers-count/Solution.sql
4091	Find Golden Hour Customers	Medium	`None`	find-golden-hour-customers/Solution.sql
2106	Find Greatest Common Divisor of Array	Easy	`Array`, `Math`, `Number Theory`, `Euclidean Algorithm`, `Greatest Common Divisor`	find-greatest-common-divisor-of-array/Solution.py
4107	Find Missing Elements	Easy	`Array`, `Hash Table`, `Sorting`	find-missing-elements/Solution.py
724	Find Pivot Index	Easy	`Array`, `Prefix Sum`	find-pivot-index/Solution.py
3865	Find Product Recommendation Pairs	Medium	`Database`	find-product-recommendation-pairs/Solution.sql
3803	Find Products with Valid Serial Numbers	Easy	`Database`	find-products-with-valid-serial-numbers/Solution.sql
3767	Find Students Who Improved	Medium	`Database`	find-students-who-improved/Solution.sql
287	Find the Duplicate Number	Medium	`Array`, `Two Pointers`, `Binary Search`, `Bit Manipulation`, `Pigeonhole Principle`, `Floyd's Cycle Finding Algorithm`	find-the-duplicate-number/Solution.py
1833	Find the Highest Altitude	Easy	`Array`, `Prefix Sum`	find-the-highest-altitude/Solution.py
28	Find the Index of the First Occurrence in a String	Easy	`Two Pointers`, `String`, `String Matching`, `Z Algorithm`, `Knuth–Morris–Pratt Algorithm`, `Boyer–Moore String-Search Algorithm`	find-the-index-of-the-first-occurrence-in-a-string/Solution.py
1892	Find Total Time Spent by Each Employee	Easy	`Database`	find-total-time-spent-by-each-employee/Solution.sql
1664	Find Users With Valid E-Mails	Easy	`Database`	find-users-with-valid-e-mails/Solution.sql
3782	Find Valid Emails	Easy	`Database`	find-valid-emails/Solution.sql
1811	Fix Names in a Table	Easy	`Database`	fix-names-in-a-table/Solution.sql
412	Fizz Buzz	Easy	`Math`, `String`, `Simulation`	fizz-buzz/Solution.py
602	Friend Requests II: Who Has the Most Friends	Medium	`Database`	friend-requests-ii-who-has-the-most-friends/Solution.sql
940	Fruit Into Baskets	Medium	`Array`, `Hash Table`, `Sliding Window`	fruit-into-baskets/Solution.py
1179	Game Play Analysis I	Easy	`Database`	game-play-analysis-i/Solution.sql
1182	Game Play Analysis IV	Medium	`Database`	game-play-analysis-iv/Solution.sql
3995	GCD of Odd and Even Sums	Easy	`Math`, `Number Theory`	gcd-of-odd-and-even-sums/Solution.py
1625	Group Sold Products By The Date	Easy	`Database`	group-sold-products-by-the-date/Solution.sql
202	Happy Number	Easy	`Hash Table`, `Math`, `Two Pointers`, `Floyd's Cycle Finding Algorithm`	happy-number/Solution.py
1292	Immediate Food Delivery II	Medium	`Database`	immediate-food-delivery-ii/Solution.sql
57	Insert Interval	Medium	`Array`	insert-interval/Solution.py
349	Intersection of Two Arrays	Easy	`Array`, `Hash Table`, `Two Pointers`, `Binary Search`, `Sorting`	intersection-of-two-arrays/Solution.py
1827	Invalid Tweets	Easy	`Database`	invalid-tweets/Solution.sql
585	Investments in 2016	Medium	`Database`	investments-in-2016/Solution.sql
205	Isomorphic Strings	Easy	`Hash Table`, `String`	isomorphic-strings/Solution.py
1528	Kids With the Greatest Number of Candies	Easy	`Array`	kids-with-the-greatest-number-of-candies/Solution.py
1327	Last Person to Fit in the Bus	Medium	`Database`	last-person-to-fit-in-the-bus/Solution.sql
2714	Left and Right Sum Differences	Easy	`Array`, `Prefix Sum`	left-and-right-sum-differences/Solution.py
58	Length of Last Word	Easy	`String`	length-of-last-word/Solution.py
3225	Length of Longest Subarray With at Most K Frequency	Medium	`Array`, `Hash Table`, `Sliding Window`	length-of-longest-subarray-with-at-most-k-frequency/Solution.py
141	Linked List Cycle	Easy	`Hash Table`, `Linked List`, `Two Pointers`, `Floyd's Cycle Finding Algorithm`	linked-list-cycle/Solution.py
142	Linked List Cycle II	Medium	`Hash Table`, `Linked List`, `Two Pointers`, `Floyd's Cycle Finding Algorithm`	linked-list-cycle-ii/Solution.py
1462	List the Products Ordered in a Period	Easy	`Database`	list-the-products-ordered-in-a-period/Solution.sql
14	Longest Common Prefix	Easy	`Array`, `String`, `Trie`	longest-common-prefix/Solution.py
128	Longest Consecutive Sequence	Medium	`Array`, `Hash Table`, `Union-Find`	longest-consecutive-sequence/Solution.py
424	Longest Repeating Character Replacement	Medium	`Hash Table`, `String`, `Sliding Window`	longest-repeating-character-replacement/Solution.py
3	Longest Substring Without Repeating Characters	Medium	`Hash Table`, `String`, `Sliding Window`	longest-substring-without-repeating-characters/Solution.py
169	Majority Element	Easy	`Array`, `Hash Table`, `Divide and Conquer`, `Sorting`, `Counting`, `Boyer–Moore Majority Vote Algorithm`	majority-element/Solution.py
229	Majority Element II	Medium	`Array`, `Hash Table`, `Sorting`, `Counting`, `Boyer–Moore Majority Vote Algorithm`	majority-element-ii/Solution.py
570	Managers with at Least 5 Direct Reports	Medium	`Database`	managers-with-at-least-5-direct-reports/Solution.sql
1268	Market Analysis I	Medium	`Database`	market-analysis-i/Solution.sql
485	Max Consecutive Ones	Easy	`Array`	max-consecutive-ones/Solution.py
1046	Max Consecutive Ones III	Medium	`Array`, `Binary Search`, `Sliding Window`, `Prefix Sum`	max-consecutive-ones-iii/Solution.py
1849	Maximum Absolute Sum of Any Subarray	Medium	`Array`, `Dynamic Programming`	maximum-absolute-sum-of-any-subarray/Solution.py
1968	Maximum Building Height	Hard	`Array`, `Math`, `Sorting`	maximum-building-height/Solution.py
164	Maximum Gap	Medium	`Array`, `Sorting`, `Bucket Sort`, `Radix Sort`, `Pigeonhole Principle`	maximum-gap/Solution.py
1961	Maximum Ice Cream Bars	Medium	`Array`, `Greedy`, `Sorting`, `Counting Sort`	maximum-ice-cream-bars/Solution.py
3349	Maximum Length Substring With Two Occurrences	Easy	`Hash Table`, `String`, `Sliding Window`	maximum-length-substring-with-two-occurrences/Solution.py
1297	Maximum Number of Balloons	Easy	`Hash Table`, `String`, `Counting`	maximum-number-of-balloons/Solution.py
628	Maximum Product of Three Numbers	Easy	`Array`, `Math`, `Sorting`	maximum-product-of-three-numbers/Solution.py
3859	Maximum Product of Two Digits	Easy	`Math`, `Sorting`	maximum-product-of-two-digits/Solution.py
1574	Maximum Product of Two Elements in an Array	Easy	`Array`, `Sorting`, `Heap (Priority Queue)`	maximum-product-of-two-elements-in-an-array/Solution.py
152	Maximum Product Subarray	Medium	`Array`, `Dynamic Programming`	maximum-product-subarray/Solution.py
53	Maximum Subarray	Medium	`Array`, `Divide and Conquer`, `Dynamic Programming`	maximum-subarray/Solution.py
1288	Maximum Subarray Sum with One Deletion	Medium	`Array`, `Dynamic Programming`	maximum-subarray-sum-with-one-deletion/Solution.py
954	Maximum Sum Circular Subarray	Medium	`Array`, `Divide and Conquer`, `Dynamic Programming`, `Queue`, `Monotonic Queue`	maximum-sum-circular-subarray/Solution.py
4	Median of Two Sorted Arrays	Hard	`Array`, `Binary Search`, `Divide and Conquer`	median-of-two-sorted-arrays/Solution.py
56	Merge Intervals	Medium	`Array`, `Sorting`, `Quicksort`	merge-intervals/Solution.py
88	Merge Sorted Array	Easy	`Array`, `Two Pointers`, `Sorting`	merge-sorted-array/Solution.js
1894	Merge Strings Alternately	Easy	`Two Pointers`, `String`	merge-strings-alternately/Solution.py
21	Merge Two Sorted Lists	Easy	`Linked List`, `Recursion`	merge-two-sorted-lists/Solution.py
908	Middle of the Linked List	Easy	`Linked List`, `Two Pointers`	middle-of-the-linked-list/Solution.py
2634	Minimum Common Value	Easy	`Array`, `Hash Table`, `Two Pointers`, `Binary Search`	minimum-common-value/Solution.py
1975	Minimum Distance to the Target Element	Easy	`Array`	minimum-distance-to-the-target-element/Solution.py
4199	Minimum Prefix Removal to Make Array Strictly Increasing	Medium	`Array`	minimum-prefix-removal-to-make-array-strictly-increasing/Solution.py
209	Minimum Size Subarray Sum	Medium	`Array`, `Binary Search`, `Sliding Window`, `Prefix Sum`	minimum-size-subarray-sum/Solution.py
76	Minimum Window Substring	Hard	`Hash Table`, `String`, `Sliding Window`	minimum-window-substring/Solution.py
268	Missing Number	Easy	`Array`, `Hash Table`, `Math`, `Binary Search`, `Bit Manipulation`, `Sorting`	missing-number/Solution.py
1317	Monthly Transactions I	Medium	`Database`	monthly-transactions-i/Solution.sql
283	Move Zeroes	Easy	`Array`, `Two Pointers`	move-zeroes/Solution.py
1480	Movie Rating	Medium	`Database`	movie-rating/Solution.sql
43	Multiply Strings	Medium	`Math`, `String`, `Simulation`	multiply-strings/Solution.py
620	Not Boring Movies	Easy	`Database`	not-boring-movies/Solution.sql
177	Nth Highest Salary	Medium	`Database`	nth-highest-salary/Solution.sql
434	Number of Segments in a String	Easy	`String`	number-of-segments-in-a-string/Solution.py
2495	Number of Unique Subjects Taught by Each Teacher	Easy	`Database`	number-of-unique-subjects-taught-by-each-teacher/Solution.sql
3820	Number of Unique XOR Triplets II	Medium	`Array`, `Math`, `Bit Manipulation`, `Enumeration`	number-of-unique-xor-triplets-ii/Solution.py
3530	Odd and Even Transactions	Medium	`Database`	odd-and-even-transactions/Solution.sql
9	Palindrome Number	Easy	`Math`	palindrome-number/Solution.py
2265	Partition Array According to Given Pivot	Medium	`Array`, `Two Pointers`, `Simulation`	partition-array-according-to-given-pivot/Solution.py
1670	Patients With a Condition	Easy	`Database`	patients-with-a-condition/Solution.sql
1773	Percentage of Users Attended a Contest	Easy	`Database`	percentage-of-users-attended-a-contest/Solution.sql
567	Permutation in String	Medium	`Hash Table`, `Two Pointers`, `String`, `Sliding Window`	permutation-in-string/Solution.py
66	Plus One	Easy	`Array`, `Math`	plus-one/Solution.py
50	Pow(x, n)	Medium	`Math`, `Recursion`	powx-n/Solution.py
1942	Primary Department for Each Employee	Easy	`Database`	primary-department-for-each-employee/Solution.sql
1278	Product Price at a Given Date	Medium	`Database`	product-price-at-a-given-date/Solution.sql
1153	Product Sales Analysis I	Easy	`Database`	product-sales-analysis-i/Solution.sql
1155	Product Sales Analysis III	Medium	`Database`	product-sales-analysis-iii/Solution.sql
1161	Project Employees I	Easy	`Database`	project-employees-i/Solution.sql
1338	Queries Quality and Percentage	Easy	`Database`	queries-quality-and-percentage/Solution.sql
178	Rank Scores	Medium	`Database`	rank-scores/Solution.sql
2271	Rearrange Array Elements by Sign	Medium	`Array`, `Two Pointers`, `Simulation`	rearrange-array-elements-by-sign/Solution.py
1908	Recyclable and Low Fat Products	Easy	`Database`	recyclable-and-low-fat-products/Solution.sql
26	Remove Duplicates from Sorted Array	Easy	`Array`, `Two Pointers`	remove-duplicates-from-sorted-array/Solution.js
80	Remove Duplicates from Sorted Array II	Medium	`Array`, `Two Pointers`	remove-duplicates-from-sorted-array-ii/Solution.js
83	Remove Duplicates from Sorted List	Easy	`Linked List`	remove-duplicates-from-sorted-list/Solution.py
82	Remove Duplicates from Sorted List II	Medium	`Linked List`, `Two Pointers`	remove-duplicates-from-sorted-list-ii/Solution.py
27	Remove Element	Easy	`Array`, `Two Pointers`	remove-element/Solution.py
19	Remove Nth Node From End of List	Medium	`Linked List`, `Two Pointers`	remove-nth-node-from-end-of-list/Solution.py
187	Repeated DNA Sequences	Medium	`Hash Table`, `String`, `Bit Manipulation`, `Sliding Window`, `Rolling Hash`, `Hash Function`, `Z Algorithm`, `Boyer–Moore String-Search Algorithm`	repeated-dna-sequences/Solution.py
1509	Replace Employee ID With The Unique Identifier	Easy	`Database`	replace-employee-id-with-the-unique-identifier/Solution.sql
1452	Restaurant Growth	Medium	`Database`	restaurant-growth/Solution.sql
3811	Reverse Degree of a String	Easy	`String`, `Simulation`	reverse-degree-of-a-string/Solution.py
344	Reverse String	Easy	`Two Pointers`, `String`	reverse-string/Solution.py
345	Reverse Vowels of a String	Easy	`Two Pointers`, `String`	reverse-vowels-of-a-string/Solution.py
151	Reverse Words in a String	Medium	`Two Pointers`, `String`	reverse-words-in-a-string/Solution.py
197	Rising Temperature	Easy	`Database`	rising-temperature/Solution.sql
1174	Sales Analysis III	Easy	`Database`	sales-analysis-iii/Solution.sql
607	Sales Person	Easy	`Database`	sales-person/Solution.sql
33	Search in Rotated Sorted Array	Medium	`Array`, `Binary Search`	search-in-rotated-sorted-array/Solution.py
81	Search in Rotated Sorted Array II	Medium	`Array`, `Binary Search`	search-in-rotated-sorted-array-ii/Solution.py
35	Search Insert Position	Easy	`Array`, `Binary Search`	search-insert-position/Solution.py
3898	Seasonal Sales Analysis	Medium	`Database`	seasonal-sales-analysis/Solution.sql
176	Second Highest Salary	Medium	`Database`	second-highest-salary/Solution.sql
2598	Shortest Distance to Target String in a Circular Array	Easy	`Array`, `String`	shortest-distance-to-target-string-in-a-circular-array/Solution.py
540	Single Element in a Sorted Array	Medium	`Array`, `Binary Search`	single-element-in-a-sorted-array/Solution.py
3626	Smallest Divisible Digit Product I	Easy	`Math`, `Enumeration`	smallest-divisible-digit-product-i/Solution.py
3869	Smallest Index With Digit Sum Equal to Index	Easy	`Array`, `Math`	smallest-index-with-digit-sum-equal-to-index/Solution.py
3236	Smallest Missing Integer Greater Than Sequential Prefix Sum	Easy	`Array`, `Hash Table`, `Sorting`	smallest-missing-integer-greater-than-sequential-prefix-sum/Solution.py
4080	Smallest Missing Multiple of K	Easy	`Array`, `Hash Table`	smallest-missing-multiple-of-k/Solution.py
3812	Smallest Palindromic Rearrangement I	Medium	`String`, `Sorting`, `Counting Sort`	smallest-palindromic-rearrangement-i/Solution.py
4284	Smallest Stable Index I	Easy	`Array`, `Prefix Sum`	smallest-stable-index-i/Solution.py
4285	Smallest Stable Index II	Medium	`Array`, `Prefix Sum`	smallest-stable-index-ii/Solution.py
75	Sort Colors	Medium	`Array`, `Two Pointers`, `Sorting`, `Quicksort`, `Bubble Sort`	sort-colors/Solution.py
1019	Squares of a Sorted Array	Easy	`Array`, `Two Pointers`, `Sorting`	squares-of-a-sorted-array/Solution.py
909	Stone Game	Medium	`Array`, `Math`, `Dynamic Programming`, `Minimax`, `Game Theory`, `Zero-Sum Game`	stone-game/Solution.py
1415	Students and Examinations	Easy	`Database`	students-and-examinations/Solution.sql
713	Subarray Product Less Than K	Medium	`Array`, `Binary Search`, `Sliding Window`, `Prefix Sum`	subarray-product-less-than-k/Solution.py
560	Subarray Sum Equals K	Medium	`Array`, `Hash Table`, `Prefix Sum`	subarray-sum-equals-k/Solution.py
30	Substring with Concatenation of All Words	Hard	`Hash Table`, `String`, `Sliding Window`	substring-with-concatenation-of-all-words/Solution.py
2728	Sum in a Matrix	Medium	`Array`, `Sorting`, `Heap (Priority Queue)`, `Matrix`, `Simulation`	sum-in-a-matrix/Solution.py
4242	Sum of GCD of Formed Pairs	Medium	`Array`, `Math`, `Two Pointers`, `Sorting`, `Simulation`, `Number Theory`	sum-of-gcd-of-formed-pairs/Solution.py
627	Swap Sex of Employees	Easy	`Database`	swap-sex-of-employees/Solution.sql
1882	The Number of Employees Which Report to Each Employee	Easy	`Database`	the-number-of-employees-which-report-to-each-employee/Solution.sql
1541	Top Travellers	Easy	`Database`	top-travellers/Solution.sql
608	Tree Node	Medium	`Database`	tree-node/Solution.sql
610	Triangle Judgement	Easy	`Database`	triangle-judgement/Solution.sql
262	Trips and Users	Hard	`Database`	trips-and-users/Solution.sql
1	Two Sum	Easy	`Array`, `Hash Table`	two-sum/Solution.py
167	Two Sum II - Input Array Is Sorted	Medium	`Array`, `Two Pointers`, `Binary Search`	two-sum-ii-input-array-is-sorted/Solution.py
1245	User Activity for the Past 30 Days I	Easy	`Database`	user-activity-for-the-past-30-days-i/Solution.sql
242	Valid Anagram	Easy	`Hash Table`, `String`, `Sorting`	valid-anagram/Solution.py
125	Valid Palindrome	Easy	`Two Pointers`, `String`	valid-palindrome/Solution.py
20	Valid Parentheses	Easy	`String`, `Stack`, `Bracket Sequences`	valid-parentheses/Solution.py
290	Word Pattern	Easy	`Hash Table`, `String`	word-pattern/Solution.py
6	Zigzag Conversion	Medium	`String`	zigzag-conversion/Solution.py

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LeetCode Solutions Archive

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Name		Name	Last commit message	Last commit date
3sum-closest		3sum-closest
3sum		3sum
4sum		4sum
actors-and-directors-who-cooperated-at-least-three-times		actors-and-directors-who-cooperated-at-least-three-times
add-binary		add-binary
add-digits		add-digits
add-two-numbers		add-two-numbers
angle-between-hands-of-a-clock		angle-between-hands-of-a-clock
article-views-i		article-views-i
average-selling-price		average-selling-price
average-time-of-process-per-machine		average-time-of-process-per-machine
bank-account-summary-ii		bank-account-summary-ii
best-time-to-buy-and-sell-stock		best-time-to-buy-and-sell-stock
big-countries		big-countries
biggest-single-number		biggest-single-number
bulls-and-cows		bulls-and-cows
calculate-special-bonus		calculate-special-bonus
capital-gainloss		capital-gainloss
check-divisibility-by-digit-sum-and-product		check-divisibility-by-digit-sum-and-product
check-if-number-has-equal-digit-count-and-digit-value		check-if-number-has-equal-digit-count-and-digit-value
classes-with-at-least-5-students		classes-with-at-least-5-students
combine-two-tables		combine-two-tables
compute-alternating-sum		compute-alternating-sum
concatenation-of-array		concatenation-of-array
confirmation-rate		confirmation-rate
consecutive-numbers		consecutive-numbers
construct-uniform-parity-array-i		construct-uniform-parity-array-i
container-with-most-water		container-with-most-water
contains-duplicate-ii		contains-duplicate-ii
contains-duplicate		contains-duplicate
count-commas-in-range-ii		count-commas-in-range-ii
count-commas-in-range		count-commas-in-range
count-salary-categories		count-salary-categories
count-submatrices-with-top-left-element-and-sum-less-than-k		count-submatrices-with-top-left-element-and-sum-less-than-k
count-the-number-of-special-characters-ii		count-the-number-of-special-characters-ii
customer-placing-the-largest-number-of-orders		customer-placing-the-largest-number-of-orders
customer-who-visited-but-did-not-make-any-transactions		customer-who-visited-but-did-not-make-any-transactions
customers-who-bought-all-products		customers-who-bought-all-products
customers-who-never-order		customers-who-never-order
daily-leads-and-partners		daily-leads-and-partners
delete-duplicate-emails		delete-duplicate-emails
department-highest-salary		department-highest-salary
department-top-three-salaries		department-top-three-salaries
distribute-elements-into-two-arrays-i		distribute-elements-into-two-arrays-i
dna-pattern-recognition		dna-pattern-recognition
duplicate-emails		duplicate-emails
employee-bonus		employee-bonus
employees-earning-more-than-their-managers		employees-earning-more-than-their-managers
employees-whose-manager-left-the-company		employees-whose-manager-left-the-company
employees-with-missing-information		employees-with-missing-information
exchange-seats		exchange-seats
find-all-anagrams-in-a-string		find-all-anagrams-in-a-string
find-books-with-no-available-copies		find-books-with-no-available-copies
find-category-recommendation-pairs		find-category-recommendation-pairs
find-covid-recovery-patients		find-covid-recovery-patients
find-customer-referee		find-customer-referee
find-first-and-last-position-of-element-in-sorted-array		find-first-and-last-position-of-element-in-sorted-array
find-followers-count		find-followers-count
find-golden-hour-customers		find-golden-hour-customers
find-greatest-common-divisor-of-array		find-greatest-common-divisor-of-array
find-missing-elements		find-missing-elements
find-pivot-index		find-pivot-index
find-product-recommendation-pairs		find-product-recommendation-pairs
find-products-with-valid-serial-numbers		find-products-with-valid-serial-numbers
find-students-who-improved		find-students-who-improved
find-the-duplicate-number		find-the-duplicate-number
find-the-highest-altitude		find-the-highest-altitude
find-the-index-of-the-first-occurrence-in-a-string		find-the-index-of-the-first-occurrence-in-a-string
find-total-time-spent-by-each-employee		find-total-time-spent-by-each-employee
find-users-with-valid-e-mails		find-users-with-valid-e-mails
find-valid-emails		find-valid-emails
fix-names-in-a-table		fix-names-in-a-table
fizz-buzz		fizz-buzz
friend-requests-ii-who-has-the-most-friends		friend-requests-ii-who-has-the-most-friends
fruit-into-baskets		fruit-into-baskets
game-play-analysis-i		game-play-analysis-i
game-play-analysis-iv		game-play-analysis-iv
gcd-of-odd-and-even-sums		gcd-of-odd-and-even-sums
group-sold-products-by-the-date		group-sold-products-by-the-date
happy-number		happy-number
immediate-food-delivery-ii		immediate-food-delivery-ii
insert-interval		insert-interval
intersection-of-two-arrays		intersection-of-two-arrays
invalid-tweets		invalid-tweets
investments-in-2016		investments-in-2016
isomorphic-strings		isomorphic-strings
kids-with-the-greatest-number-of-candies		kids-with-the-greatest-number-of-candies
last-person-to-fit-in-the-bus		last-person-to-fit-in-the-bus
left-and-right-sum-differences		left-and-right-sum-differences
length-of-last-word		length-of-last-word
length-of-longest-subarray-with-at-most-k-frequency		length-of-longest-subarray-with-at-most-k-frequency
linked-list-cycle-ii		linked-list-cycle-ii
linked-list-cycle		linked-list-cycle
list-the-products-ordered-in-a-period		list-the-products-ordered-in-a-period
longest-common-prefix		longest-common-prefix
longest-consecutive-sequence		longest-consecutive-sequence
longest-repeating-character-replacement		longest-repeating-character-replacement
longest-substring-without-repeating-characters		longest-substring-without-repeating-characters
majority-element-ii		majority-element-ii
majority-element		majority-element

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