Leeeetcode

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

LeetCode Topics

Database

0180-consecutive-numbers
0183-customers-who-never-order
0197-rising-temperature
0570-managers-with-at-least-5-direct-reports
0584-find-customer-referee
0595-big-countries
0596-classes-with-at-least-5-students
0602-friend-requests-ii-who-has-the-most-friends
0610-triangle-judgement
0619-biggest-single-number
0620-not-boring-movies
0626-exchange-seats
1135-customers-who-bought-all-products
1153-product-sales-analysis-i
1155-product-sales-analysis-iii
1182-game-play-analysis-iv
1245-user-activity-for-the-past-30-days-i
1258-article-views-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
1452-restaurant-growth
1480-movie-rating
1509-replace-employee-id-with-the-unique-identifier
1724-customer-who-visited-but-did-not-make-any-transactions
1801-average-time-of-process-per-machine
1811-fix-names-in-a-table
1827-invalid-tweets
1877-find-followers-count
1882-the-number-of-employees-which-report-to-each-employee
1908-recyclable-and-low-fat-products
1942-primary-department-for-each-employee
2024-calculate-special-bonus
2057-count-salary-categories
2087-confirmation-rate
2127-employees-whose-manager-left-the-company
2495-number-of-unique-subjects-taught-by-each-teacher

Array

0001-two-sum
0004-median-of-two-sorted-arrays
0011-container-with-most-water
0026-remove-duplicates-from-sorted-array
0027-remove-element
0034-find-first-and-last-position-of-element-in-sorted-array
0035-search-insert-position
0037-sudoku-solver
0039-combination-sum
0046-permutations
0047-permutations-ii
0048-rotate-image
0051-n-queens
0053-maximum-subarray
0059-spiral-matrix-ii
0063-unique-paths-ii
0064-minimum-path-sum
0066-plus-one
0075-sort-colors
0078-subsets
0079-word-search
0090-subsets-ii
0120-triangle
0121-best-time-to-buy-and-sell-stock
0128-longest-consecutive-sequence
0130-surrounded-regions
0152-maximum-product-subarray
0169-majority-element
0200-number-of-islands
0213-house-robber-ii
0219-contains-duplicate-ii
0228-summary-ranges
0239-sliding-window-maximum
0268-missing-number
0283-move-zeroes
0287-find-the-duplicate-number
0322-coin-change
0399-evaluate-division
0455-assign-cookies
0494-target-sum
0518-coin-change-ii
0526-beautiful-arrangement
0542-01-matrix
0560-subarray-sum-equals-k
0594-longest-harmonious-subsequence
0733-flood-fill
0792-binary-search
0797-rabbits-in-forest
0924-fair-candy-swap
0928-surface-area-of-3d-shapes
0958-sort-array-by-parity-ii
1022-unique-paths-iii
1036-rotting-oranges
1073-number-of-enclaves
1227-number-of-equivalent-domino-pairs
1293-three-consecutive-odds
1478-maximum-number-of-events-that-can-be-attended
1510-find-lucky-integer-in-an-array
1995-finding-pairs-with-a-certain-sum
2265-partition-array-according-to-given-pivot
2271-rearrange-array-elements-by-sign
2308-divide-array-into-equal-pairs
2320-find-all-k-distant-indices-in-an-array
2478-longest-nice-subarray
2707-merge-two-2d-arrays-by-summing-values
2915-count-of-interesting-subarrays
3430-count-days-without-meetings

Backtracking

0022-generate-parentheses
0037-sudoku-solver
0039-combination-sum
0046-permutations
0047-permutations-ii
0051-n-queens
0052-n-queens-ii
0078-subsets
0079-word-search
0089-gray-code
0090-subsets-ii
0131-palindrome-partitioning
0494-target-sum
0526-beautiful-arrangement
1022-unique-paths-iii

Bit Manipulation

0029-divide-two-integers
0067-add-binary
0078-subsets
0089-gray-code
0090-subsets-ii
0268-missing-number
0287-find-the-duplicate-number
0389-find-the-difference
0526-beautiful-arrangement
0767-prime-number-of-set-bits-in-binary-representation
1022-unique-paths-iii
2308-divide-array-into-equal-pairs
2478-longest-nice-subarray
3600-find-the-k-th-character-in-string-game-i
3601-find-the-k-th-character-in-string-game-ii

String

0006-zigzag-conversion
0008-string-to-integer-atoi
0013-roman-to-integer
0020-valid-parentheses
0022-generate-parentheses
0067-add-binary
0079-word-search
0127-word-ladder
0131-palindrome-partitioning
0241-different-ways-to-add-parentheses
0290-word-pattern
0389-find-the-difference
0399-evaluate-division
0451-sort-characters-by-frequency
2260-divide-a-string-into-groups-of-size-k
2309-maximize-number-of-subsequences-in-a-string
3617-find-the-original-typed-string-i
3618-find-the-original-typed-string-ii

Dynamic Programming

0022-generate-parentheses
0053-maximum-subarray
0062-unique-paths
0063-unique-paths-ii
0064-minimum-path-sum
0070-climbing-stairs
0120-triangle
0121-best-time-to-buy-and-sell-stock
0131-palindrome-partitioning
0152-maximum-product-subarray
0213-house-robber-ii
0241-different-ways-to-add-parentheses
0322-coin-change
0494-target-sum
0518-coin-change-ii
0526-beautiful-arrangement
0542-01-matrix
0803-cheapest-flights-within-k-stops
3618-find-the-original-typed-string-ii

Hash Table

0001-two-sum
0013-roman-to-integer
0037-sudoku-solver
0127-word-ladder
0128-longest-consecutive-sequence
0160-intersection-of-two-linked-lists
0169-majority-element
0219-contains-duplicate-ii
0268-missing-number
0290-word-pattern
0389-find-the-difference
0451-sort-characters-by-frequency
0560-subarray-sum-equals-k
0594-longest-harmonious-subsequence
0653-two-sum-iv-input-is-a-bst
0797-rabbits-in-forest
0924-fair-candy-swap
1227-number-of-equivalent-domino-pairs
1510-find-lucky-integer-in-an-array
1995-finding-pairs-with-a-certain-sum
2308-divide-array-into-equal-pairs
2707-merge-two-2d-arrays-by-summing-values
2915-count-of-interesting-subarrays

Two Pointers

0011-container-with-most-water
0026-remove-duplicates-from-sorted-array
0027-remove-element
0075-sort-colors
0160-intersection-of-two-linked-lists
0283-move-zeroes
0287-find-the-duplicate-number
0455-assign-cookies
0653-two-sum-iv-input-is-a-bst
0958-sort-array-by-parity-ii
2265-partition-array-according-to-given-pivot
2271-rearrange-array-elements-by-sign
2320-find-all-k-distant-indices-in-an-array
2707-merge-two-2d-arrays-by-summing-values

Simulation

0059-spiral-matrix-ii
0067-add-binary
1642-water-bottles
2260-divide-a-string-into-groups-of-size-k
2265-partition-array-according-to-given-pivot
2271-rearrange-array-elements-by-sign
3600-find-the-k-th-character-in-string-game-i

Math

0002-add-two-numbers
0007-reverse-integer
0013-roman-to-integer
0029-divide-two-integers
0048-rotate-image
0062-unique-paths
0066-plus-one
0067-add-binary
0070-climbing-stairs
0089-gray-code
0241-different-ways-to-add-parentheses
0268-missing-number
0767-prime-number-of-set-bits-in-binary-representation
0797-rabbits-in-forest
0928-surface-area-of-3d-shapes
1642-water-bottles
1889-check-if-number-is-a-sum-of-powers-of-three
2649-count-total-number-of-colored-cells
3600-find-the-k-th-character-in-string-game-i
3601-find-the-k-th-character-in-string-game-ii

Binary Search

0004-median-of-two-sorted-arrays
0034-find-first-and-last-position-of-element-in-sorted-array
0035-search-insert-position
0268-missing-number
0287-find-the-duplicate-number
0792-binary-search
0924-fair-candy-swap

Sliding Window

0219-contains-duplicate-ii
0239-sliding-window-maximum
0594-longest-harmonious-subsequence
2478-longest-nice-subarray

Counting

0169-majority-element
0451-sort-characters-by-frequency
0594-longest-harmonious-subsequence
1227-number-of-equivalent-domino-pairs
1510-find-lucky-integer-in-an-array
2308-divide-array-into-equal-pairs

Divide and Conquer

0004-median-of-two-sorted-arrays
0053-maximum-subarray
0169-majority-element

Sorting

0047-permutations-ii
0075-sort-colors
0169-majority-element
0268-missing-number
0389-find-the-difference
0451-sort-characters-by-frequency
0455-assign-cookies
0594-longest-harmonious-subsequence
0924-fair-candy-swap
0958-sort-array-by-parity-ii
1478-maximum-number-of-events-that-can-be-attended
3430-count-days-without-meetings

Stack

0020-valid-parentheses
0225-implement-stack-using-queues
0232-implement-queue-using-stacks

Greedy

0011-container-with-most-water
0455-assign-cookies
0797-rabbits-in-forest
1478-maximum-number-of-events-that-can-be-attended
2309-maximize-number-of-subsequences-in-a-string

Prefix Sum

0560-subarray-sum-equals-k
2309-maximize-number-of-subsequences-in-a-string
2915-count-of-interesting-subarrays
3618-find-the-original-typed-string-ii

Design

0225-implement-stack-using-queues
0232-implement-queue-using-stacks
1995-finding-pairs-with-a-certain-sum

Queue

0225-implement-stack-using-queues
0232-implement-queue-using-stacks
0239-sliding-window-maximum

Heap (Priority Queue)

0239-sliding-window-maximum
0451-sort-characters-by-frequency
0803-cheapest-flights-within-k-stops
1478-maximum-number-of-events-that-can-be-attended

Monotonic Queue

0239-sliding-window-maximum

Linked List

0002-add-two-numbers
0021-merge-two-sorted-lists
0024-swap-nodes-in-pairs
0025-reverse-nodes-in-k-group
0083-remove-duplicates-from-sorted-list
0160-intersection-of-two-linked-lists
0203-remove-linked-list-elements
0206-reverse-linked-list

Recursion

0002-add-two-numbers
0021-merge-two-sorted-lists
0024-swap-nodes-in-pairs
0025-reverse-nodes-in-k-group
0203-remove-linked-list-elements
0206-reverse-linked-list
0241-different-ways-to-add-parentheses
3600-find-the-k-th-character-in-string-game-i
3601-find-the-k-th-character-in-string-game-ii

Memoization

0070-climbing-stairs
0241-different-ways-to-add-parentheses

Bucket Sort

0451-sort-characters-by-frequency

Geometry

0928-surface-area-of-3d-shapes

Matrix

0037-sudoku-solver
0048-rotate-image
0059-spiral-matrix-ii
0063-unique-paths-ii
0064-minimum-path-sum
0079-word-search
0130-surrounded-regions
0200-number-of-islands
0542-01-matrix
0733-flood-fill
0928-surface-area-of-3d-shapes
1022-unique-paths-iii
1036-rotting-oranges
1073-number-of-enclaves

Tree

0099-recover-binary-search-tree
0129-sum-root-to-leaf-numbers
0226-invert-binary-tree
0230-kth-smallest-element-in-a-bst
0543-diameter-of-binary-tree
0653-two-sum-iv-input-is-a-bst
0783-search-in-a-binary-search-tree

Depth-First Search

0079-word-search
0099-recover-binary-search-tree
0129-sum-root-to-leaf-numbers
0130-surrounded-regions
0200-number-of-islands
0210-course-schedule-ii
0226-invert-binary-tree
0230-kth-smallest-element-in-a-bst
0399-evaluate-division
0543-diameter-of-binary-tree
0547-number-of-provinces
0653-two-sum-iv-input-is-a-bst
0733-flood-fill
0803-cheapest-flights-within-k-stops
0820-find-eventual-safe-states
1073-number-of-enclaves

Breadth-First Search

0127-word-ladder
0130-surrounded-regions
0200-number-of-islands
0210-course-schedule-ii
0226-invert-binary-tree
0322-coin-change
0399-evaluate-division
0542-01-matrix
0547-number-of-provinces
0653-two-sum-iv-input-is-a-bst
0733-flood-fill
0803-cheapest-flights-within-k-stops
0820-find-eventual-safe-states
1036-rotting-oranges
1073-number-of-enclaves

Binary Search Tree

0099-recover-binary-search-tree
0230-kth-smallest-element-in-a-bst
0653-two-sum-iv-input-is-a-bst
0783-search-in-a-binary-search-tree

Binary Tree

0099-recover-binary-search-tree
0129-sum-root-to-leaf-numbers
0226-invert-binary-tree
0230-kth-smallest-element-in-a-bst
0543-diameter-of-binary-tree
0653-two-sum-iv-input-is-a-bst
0783-search-in-a-binary-search-tree

Combinatorics

0062-unique-paths

Bitmask

0526-beautiful-arrangement

Union Find

0128-longest-consecutive-sequence
0130-surrounded-regions
0200-number-of-islands
0399-evaluate-division
0547-number-of-provinces
1073-number-of-enclaves

Graph

0210-course-schedule-ii
0399-evaluate-division
0547-number-of-provinces
0803-cheapest-flights-within-k-stops
0820-find-eventual-safe-states

Topological Sort

0210-course-schedule-ii
0820-find-eventual-safe-states

Shortest Path

0399-evaluate-division
0803-cheapest-flights-within-k-stops