leetcode

A collection of LeetCode questions to ace the coding interview! - Created using LeetHub v2

LeetCode Topics

Linked List

0002-add-two-numbers
0019-remove-nth-node-from-end-of-list
0021-merge-two-sorted-lists
0024-swap-nodes-in-pairs
0083-remove-duplicates-from-sorted-list
0206-reverse-linked-list

Math

0002-add-two-numbers
0007-reverse-integer
0009-palindrome-number
0012-integer-to-roman
0013-roman-to-integer
0043-multiply-strings
0048-rotate-image
0066-plus-one
0069-sqrtx
0070-climbing-stairs
0089-gray-code
0096-unique-binary-search-trees
0189-rotate-array

Recursion

0002-add-two-numbers
0010-regular-expression-matching
0021-merge-two-sorted-lists
0024-swap-nodes-in-pairs
0044-wildcard-matching
0206-reverse-linked-list

Hash Table

0001-two-sum
0003-longest-substring-without-repeating-characters
0012-integer-to-roman
0013-roman-to-integer
0017-letter-combinations-of-a-phone-number
0036-valid-sudoku
0037-sudoku-solver
0041-first-missing-positive
0049-group-anagrams
0073-set-matrix-zeroes
0128-longest-consecutive-sequence
0217-contains-duplicate
0290-word-pattern
0442-find-all-duplicates-in-an-array
1016-subarray-sums-divisible-by-k
2483-task-scheduler-ii

String

0003-longest-substring-without-repeating-characters
0006-zigzag-conversion
0010-regular-expression-matching
0012-integer-to-roman
0013-roman-to-integer
0014-longest-common-prefix
0017-letter-combinations-of-a-phone-number
0022-generate-parentheses
0038-count-and-say
0043-multiply-strings
0044-wildcard-matching
0049-group-anagrams
0058-length-of-last-word
0065-valid-number
0068-text-justification
0072-edit-distance
0093-restore-ip-addresses
0125-valid-palindrome
0257-binary-tree-paths
0290-word-pattern

Sliding Window

0003-longest-substring-without-repeating-characters

Array

0001-two-sum
0011-container-with-most-water
0015-3sum
0016-3sum-closest
0018-4sum
0026-remove-duplicates-from-sorted-array
0036-valid-sudoku
0037-sudoku-solver
0039-combination-sum
0040-combination-sum-ii
0041-first-missing-positive
0046-permutations
0047-permutations-ii
0048-rotate-image
0049-group-anagrams
0051-n-queens
0053-maximum-subarray
0066-plus-one
0068-text-justification
0073-set-matrix-zeroes
0075-sort-colors
0088-merge-sorted-array
0108-convert-sorted-array-to-binary-search-tree
0120-triangle
0121-best-time-to-buy-and-sell-stock
0128-longest-consecutive-sequence
0130-surrounded-regions
0136-single-number
0189-rotate-array
0217-contains-duplicate
0238-product-of-array-except-self
0240-search-a-2d-matrix-ii
0284-peeking-iterator
0287-find-the-duplicate-number
0442-find-all-duplicates-in-an-array
1016-subarray-sums-divisible-by-k
1478-maximum-number-of-events-that-can-be-attended
2483-task-scheduler-ii
3628-find-minimum-time-to-reach-last-room-ii

Two Pointers

0011-container-with-most-water
0015-3sum
0016-3sum-closest
0018-4sum
0019-remove-nth-node-from-end-of-list
0026-remove-duplicates-from-sorted-array
0075-sort-colors
0088-merge-sorted-array
0125-valid-palindrome
0189-rotate-array
0287-find-the-duplicate-number

Database

0175-combine-two-tables
0176-second-highest-salary
0177-nth-highest-salary
0178-rank-scores
0180-consecutive-numbers
0182-duplicate-emails
0183-customers-who-never-order
0184-department-highest-salary
0185-department-top-three-salaries
0196-delete-duplicate-emails
0197-rising-temperature
0262-trips-and-users
0570-managers-with-at-least-5-direct-reports
0577-employee-bonus
0584-find-customer-referee
0585-investments-in-2016
0586-customer-placing-the-largest-number-of-orders
0595-big-countries
0596-classes-with-at-least-5-students
0602-friend-requests-ii-who-has-the-most-friends
0607-sales-person
0608-tree-node
0610-triangle-judgement
0619-biggest-single-number
0620-not-boring-movies
0626-exchange-seats
0627-swap-salary
1135-customers-who-bought-all-products
1136-actors-and-directors-who-cooperated-at-least-three-times
1153-product-sales-analysis-i
1155-product-sales-analysis-iii
1161-project-employees-i
1174-sales-analysis-iii
1179-game-play-analysis-i
1182-game-play-analysis-iv
1245-user-activity-for-the-past-30-days-i
1258-article-views-i
1268-market-analysis-i
1278-product-price-at-a-given-date
1292-immediate-food-delivery-ii
1317-monthly-transactions-i
1327-last-person-to-fit-in-the-bus
1338-queries-quality-and-percentage
1390-average-selling-price
1415-students-and-examinations
1452-restaurant-growth
1480-movie-rating
1509-replace-employee-id-with-the-unique-identifier
1625-group-sold-products-by-the-date
1664-find-users-with-valid-e-mails
1670-patients-with-a-condition
1724-customer-who-visited-but-did-not-make-any-transactions
1773-percentage-of-users-attended-a-contest
1801-average-time-of-process-per-machine
1811-fix-names-in-a-table
1827-invalid-tweets
1837-daily-leads-and-partners
1877-find-followers-count
1908-recyclable-and-low-fat-products
1942-primary-department-for-each-employee
2057-count-salary-categories
2087-confirmation-rate
2110-employees-with-missing-information
2127-employees-whose-manager-left-the-company
2495-number-of-unique-subjects-taught-by-each-teacher

Prefix Sum

0238-product-of-array-except-self
1016-subarray-sums-divisible-by-k

Backtracking

0017-letter-combinations-of-a-phone-number
0022-generate-parentheses
0037-sudoku-solver
0039-combination-sum
0040-combination-sum-ii
0046-permutations
0047-permutations-ii
0051-n-queens
0052-n-queens-ii
0089-gray-code
0093-restore-ip-addresses
0257-binary-tree-paths

Sorting

0015-3sum
0016-3sum-closest
0018-4sum
0047-permutations-ii
0049-group-anagrams
0075-sort-colors
0088-merge-sorted-array
0217-contains-duplicate
1478-maximum-number-of-events-that-can-be-attended

Trie

0014-longest-common-prefix

Dynamic Programming

0010-regular-expression-matching
0022-generate-parentheses
0044-wildcard-matching
0053-maximum-subarray
0070-climbing-stairs
0072-edit-distance
0096-unique-binary-search-trees
0120-triangle
0121-best-time-to-buy-and-sell-stock

Greedy

0011-container-with-most-water
0044-wildcard-matching
1478-maximum-number-of-events-that-can-be-attended

Stack

0094-binary-tree-inorder-traversal
0155-min-stack
0173-binary-search-tree-iterator
0937-online-stock-span

Design

0155-min-stack
0173-binary-search-tree-iterator
0284-peeking-iterator
0937-online-stock-span

Monotonic Stack

0937-online-stock-span

Data Stream

0937-online-stock-span

Divide and Conquer

0053-maximum-subarray
0108-convert-sorted-array-to-binary-search-tree
0240-search-a-2d-matrix-ii

Tree

0094-binary-tree-inorder-traversal
0096-unique-binary-search-trees
0098-validate-binary-search-tree
0100-same-tree
0108-convert-sorted-array-to-binary-search-tree
0110-balanced-binary-tree
0173-binary-search-tree-iterator
0257-binary-tree-paths

Binary Search Tree

0069-sqrtx
0096-unique-binary-search-trees
0098-validate-binary-search-tree
0108-convert-sorted-array-to-binary-search-tree
0173-binary-search-tree-iterator
0240-search-a-2d-matrix-ii
0287-find-the-duplicate-number

Binary Tree

0094-binary-tree-inorder-traversal
0096-unique-binary-search-trees
0098-validate-binary-search-tree
0100-same-tree
0108-convert-sorted-array-to-binary-search-tree
0110-balanced-binary-tree
0173-binary-search-tree-iterator
0257-binary-tree-paths

Matrix

0036-valid-sudoku
0037-sudoku-solver
0048-rotate-image
0073-set-matrix-zeroes
0130-surrounded-regions
0240-search-a-2d-matrix-ii
3628-find-minimum-time-to-reach-last-room-ii

Depth-First Search

0094-binary-tree-inorder-traversal
0098-validate-binary-search-tree
0100-same-tree
0110-balanced-binary-tree
0130-surrounded-regions
0257-binary-tree-paths

Bit Manipulation

0089-gray-code
0136-single-number
0287-find-the-duplicate-number

Iterator

0173-binary-search-tree-iterator
0284-peeking-iterator

Simulation

0043-multiply-strings
0068-text-justification
2483-task-scheduler-ii

Heap (Priority Queue)

1478-maximum-number-of-events-that-can-be-attended
3628-find-minimum-time-to-reach-last-room-ii

Breadth-First Search

0100-same-tree
0130-surrounded-regions

Graph

3628-find-minimum-time-to-reach-last-room-ii

Shortest Path

3628-find-minimum-time-to-reach-last-room-ii

Union Find

0128-longest-consecutive-sequence
0130-surrounded-regions

Memoization

0070-climbing-stairs