Leetcode

Collection of LeetCode questions to ace the coding interview! - Created using LeetHub

LeetCode Topics

Array

0001-two-sum
0015-3sum
0016-3sum-closest
0031-next-permutation
0034-find-first-and-last-position-of-element-in-sorted-array
0035-search-insert-position
0036-valid-sudoku
0040-combination-sum-ii
0041-first-missing-positive
0045-jump-game-ii
0049-group-anagrams
0051-n-queens
0057-insert-interval
0066-plus-one
0073-set-matrix-zeroes
0074-search-a-2d-matrix
0075-sort-colors
0078-subsets
0079-word-search
0084-largest-rectangle-in-histogram
0085-maximal-rectangle
0106-construct-binary-tree-from-inorder-and-postorder-traversal
0118-pascals-triangle
0120-triangle
0128-longest-consecutive-sequence
0130-surrounded-regions
0135-candy
0137-single-number-ii
0139-word-break
0153-find-minimum-in-rotated-sorted-array
0154-find-minimum-in-rotated-sorted-array-ii
0167-two-sum-ii-input-array-is-sorted
0169-majority-element
0179-largest-number
0209-minimum-size-subarray-sum
0212-word-search-ii
0217-contains-duplicate
0219-contains-duplicate-ii
0228-summary-ranges
0229-majority-element-ii
0238-product-of-array-except-self
0260-single-number-iii
0300-longest-increasing-subsequence
0312-burst-balloons
0322-coin-change
0324-wiggle-sort-ii
0347-top-k-frequent-elements
0368-largest-divisible-subset
0373-find-k-pairs-with-smallest-sums
0376-wiggle-subsequence
0377-combination-sum-iv
0378-kth-smallest-element-in-a-sorted-matrix
0410-split-array-largest-sum
0413-arithmetic-slices
0416-partition-equal-subset-sum
0421-maximum-xor-of-two-numbers-in-an-array
0435-non-overlapping-intervals
0436-find-right-interval
0447-number-of-boomerangs
0474-ones-and-zeroes
0493-reverse-pairs
0494-target-sum
0498-diagonal-traverse
0518-coin-change-ii
0525-contiguous-array
0539-minimum-time-difference
0560-subarray-sum-equals-k
0594-longest-harmonious-subsequence
0605-can-place-flowers
0621-task-scheduler
0624-maximum-distance-in-arrays
0628-maximum-product-of-three-numbers
0665-non-decreasing-array
0674-longest-continuous-increasing-subsequence
0691-stickers-to-spell-word
0719-find-k-th-smallest-pair-distance
0729-my-calendar-i
0731-my-calendar-ii
0747-min-cost-climbing-stairs
0780-max-chunks-to-make-sorted
0794-swim-in-rising-water
0811-number-of-subarrays-with-bounded-maximum
0835-linked-list-components
0859-design-circular-deque
0860-design-circular-queue
0870-magic-squares-in-grid
0882-peak-index-in-a-mountain-array
0906-walking-robot-simulation
0940-fruit-into-baskets
0948-sort-an-array
0952-word-subsets
0971-shortest-bridge
1002-maximum-width-ramp
1025-minimum-cost-for-tickets
1036-rotting-oranges
1049-minimum-domino-rotations-for-equal-row
1063-best-sightseeing-pair
1096-maximum-sum-of-two-non-overlapping-subarrays
1147-flip-columns-for-maximum-number-of-equal-rows
1207-delete-nodes-and-return-forest
1227-number-of-equivalent-domino-pairs
1242-matrix-block-sum
1256-rank-transform-of-an-array
1293-three-consecutive-odds
1294-range-frequency-queries
1310-watering-plants
1325-path-with-maximum-probability
1333-sort-the-jumbled-numbers
1335-maximum-candies-allocated-to-k-children
1350-remove-sub-folders-from-the-filesystem
1352-maximum-profit-in-job-scheduling
1353-find-resultant-array-after-removing-anagrams
1364-tuple-with-same-product
1396-count-servers-that-communicate
1402-count-square-submatrices-with-all-ones
1421-find-numbers-with-even-number-of-digits
1426-find-n-unique-integers-sum-up-to-zero
1435-xor-queries-of-a-subarray
1477-product-of-the-last-k-numbers
1496-lucky-numbers-in-a-matrix
1497-design-a-stack-with-increment-operation
1511-count-number-of-teams
1524-string-matching-in-an-array
1570-final-prices-with-a-special-discount-in-a-shop
1586-longest-subarray-of-1s-after-deleting-one-element
1603-running-sum-of-1d-array
1615-range-sum-of-sorted-subarray-sums
1620-check-if-array-pairs-are-divisible-by-k
1628-count-submatrices-with-all-ones
1646-kth-missing-positive-number
1656-count-good-triplets
1679-shortest-subarray-to-be-removed-to-make-array-sorted
1711-find-valid-matrix-given-row-and-column-sums
1741-sort-array-by-increasing-frequency
1744-number-of-ways-to-form-a-target-string-given-a-dictionary
1755-defuse-the-bomb
1757-minimum-jumps-to-reach-home
1762-furthest-building-you-can-reach
1766-minimum-number-of-removals-to-make-mountain-array
1776-minimum-operations-to-reduce-x-to-zero
1786-count-the-number-of-consistent-strings
1849-maximum-absolute-sum-of-any-subarray
1851-maximum-number-of-events-that-can-be-attended-ii
1876-map-of-highest-peak
1878-check-if-array-is-sorted-and-rotated
1886-minimum-limit-of-balls-in-a-bag
1895-minimum-number-of-operations-to-move-all-balls-to-each-box
1917-maximum-average-pass-ratio
1923-sentence-similarity-iii
1927-maximum-ascending-subarray-sum
1940-maximum-xor-for-each-query
1962-single-threaded-cpu
1972-rotating-the-box
1993-sum-of-all-subset-xor-totals
1995-finding-pairs-with-a-certain-sum
2006-find-the-student-that-will-replace-the-chalk
2026-merge-triplets-to-form-target-triplet
2034-minimum-absolute-difference-queries
2035-count-sub-islands
2048-build-array-from-permutation
2054-the-number-of-the-smallest-unoccupied-chair
2089-maximum-matrix-sum
2107-find-unique-binary-string
2132-convert-1d-array-into-2d-array
2144-maximum-difference-between-increasing-elements
2145-grid-game
2155-find-missing-observations
2160-minimum-operations-to-make-a-uni-value-grid
2164-two-best-non-overlapping-events
2170-count-number-of-maximum-bitwise-or-subsets
2179-most-beautiful-item-for-each-query
2188-minimized-maximum-of-products-distributed-to-any-store
2204-find-subsequence-of-length-k-with-the-largest-sum
2215-finding-3-digit-even-numbers
2219-maximum-number-of-words-found-in-sentences
2232-adding-spaces-to-a-string
2237-longest-palindrome-by-concatenating-two-letter-words
2240-intervals-between-identical-elements
2255-minimum-swaps-to-group-all-1s-together-ii
2262-solving-questions-with-brainpower
2265-partition-array-according-to-given-pivot
2277-count-equal-and-divisible-pairs-in-an-array
2285-design-bitset
2289-minimum-operations-to-make-the-array-alternating
2292-counting-words-with-a-given-prefix
2294-minimum-time-to-complete-trips
2306-create-binary-tree-from-descriptions
2308-divide-array-into-equal-pairs
2316-count-hills-and-valleys-in-an-array
2320-find-all-k-distant-indices-in-an-array
2343-count-unguarded-cells-in-the-grid
2356-largest-combination-with-bitwise-and-greater-than-zero
2358-number-of-ways-to-split-array
2387-partition-array-such-that-maximum-difference-is-k
2394-count-subarrays-with-score-less-than-k
2411-spiral-matrix-iv
2437-maximum-number-of-groups-entering-a-competition
2448-count-number-of-bad-pairs
2473-max-sum-of-a-pair-with-equal-sum-of-digits
2478-longest-nice-subarray
2483-task-scheduler-ii
2488-divide-intervals-into-minimum-number-of-groups
2494-sum-of-prefix-scores-of-strings
2497-maximum-matching-of-players-with-trainers
2498-smallest-subarrays-with-maximum-bitwise-or
2502-sort-the-people
2503-longest-subarray-with-maximum-bitwise-and
2533-bitwise-xor-of-all-pairings
2545-height-of-binary-tree-after-subtree-removal-queries
2551-apply-operations-to-an-array
2552-maximum-sum-of-distinct-subarrays-with-length-k
2554-minimum-total-distance-traveled
2567-closest-nodes-queries-in-a-binary-search-tree
2581-divide-players-into-teams-of-equal-skill
2586-longest-square-streak-in-an-array
2600-maximum-tastiness-of-candy-basket
2614-maximum-count-of-positive-integer-and-negative-integer
2616-maximal-score-after-applying-k-operations
2626-count-the-number-of-good-subarrays
2636-maximum-subsequence-score
2640-maximum-number-of-integers-to-choose-from-a-range-i
2665-minimum-time-to-repair-cars
2673-maximize-win-from-two-segments
2685-first-completely-painted-row-or-column
2691-count-vowel-strings-in-ranges
2692-take-gifts-from-the-richest-pile
2695-find-score-of-an-array-after-marking-all-elements
2699-count-the-number-of-fair-pairs
2707-merge-two-2d-arrays-by-summing-values
2711-minimum-time-to-visit-a-cell-in-a-grid
2720-minimize-the-maximum-difference-of-pairs
2727-number-of-senior-citizens
2755-extra-characters-in-a-string
2766-find-the-prefix-common-array-of-two-arrays
2792-neighboring-bitwise-xor
2794-maximum-number-of-moves-in-a-grid
2808-painting-the-walls
2856-count-complete-subarrays-in-an-array
2868-continuous-subarrays
2888-minimum-index-of-a-valid-split
2891-maximum-beauty-of-an-array-after-applying-operation
2915-count-of-interesting-subarrays
3031-construct-product-matrix
3142-longest-unequal-adjacent-groups-subsequence-ii
3143-longest-unequal-adjacent-groups-subsequence-i
3152-maximum-value-of-an-ordered-triplet-ii
3154-maximum-value-of-an-ordered-triplet-i
3171-minimum-equal-sum-of-two-arrays-after-replacing-zeros
3194-find-words-containing-character
3209-minimum-number-of-coins-for-fruits
3213-count-subarrays-where-max-element-appears-at-least-k-times
3227-find-missing-and-repeated-values
3228-maximum-size-of-a-set-after-removals
3231-minimum-number-of-coins-to-be-added
3241-divide-array-into-arrays-with-max-difference
3242-count-elements-with-maximum-frequency
3251-maximum-area-of-longest-diagonal-rectangle
3278-find-the-number-of-ways-to-place-people-i
3291-find-if-array-can-be-sorted
3309-count-prefix-and-suffix-pairs-i
3321-type-of-triangle
3329-find-the-length-of-the-longest-common-prefix
3332-minimum-operations-to-exceed-threshold-value-ii
3372-longest-strictly-increasing-or-strictly-decreasing-subarray
3380-shortest-subarray-with-or-at-least-k-ii
3430-count-days-without-meetings
3434-find-the-number-of-distinct-colors-among-the-balls
3475-minimum-operations-to-make-binary-array-elements-equal-to-one-i
3483-alternating-groups-ii
3490-find-the-maximum-length-of-valid-subsequence-i
3491-find-the-maximum-length-of-valid-subsequence-ii
3501-delete-nodes-from-linked-list-present-in-array
3517-shortest-distance-after-road-addition-queries-i
3522-find-the-power-of-k-size-subarrays-i
3555-final-array-state-after-k-multiplication-operations-i
3612-adjacent-increasing-subarrays-detection-i
3621-minimum-operations-to-make-array-values-equal-to-k
3627-find-minimum-time-to-reach-last-room-i
3628-find-minimum-time-to-reach-last-room-ii
3639-zero-array-transformation-i
3643-zero-array-transformation-ii
3656-minimum-number-of-operations-to-make-elements-in-array-distinct
3685-count-subarrays-of-length-three-with-a-condition
3702-maximum-subarray-with-equal-products
3732-calculate-score-after-performing-instructions
3738-make-array-non-decreasing
3743-reschedule-meetings-for-maximum-free-time-i
3747-maximum-difference-between-adjacent-elements-in-a-circular-array
3788-maximum-unique-subarray-sum-after-deletion
3790-fruits-into-baskets-ii
3934-coupon-code-validator

Hash Table

0001-two-sum
0036-valid-sudoku
0041-first-missing-positive
0049-group-anagrams
0073-set-matrix-zeroes
0106-construct-binary-tree-from-inorder-and-postorder-traversal
0128-longest-consecutive-sequence
0133-clone-graph
0138-copy-list-with-random-pointer
0139-word-break
0141-linked-list-cycle
0146-lru-cache
0169-majority-element
0205-isomorphic-strings
0208-implement-trie-prefix-tree
0217-contains-duplicate
0219-contains-duplicate-ii
0229-majority-element-ii
0242-valid-anagram
0347-top-k-frequent-elements
0383-ransom-note
0421-maximum-xor-of-two-numbers-in-an-array
0424-longest-repeating-character-replacement
0433-minimum-genetic-mutation
0438-find-all-anagrams-in-a-string
0447-number-of-boomerangs
0460-lfu-cache
0508-most-frequent-subtree-sum
0525-contiguous-array
0560-subarray-sum-equals-k
0567-permutation-in-string
0594-longest-harmonious-subsequence
0621-task-scheduler
0768-partition-labels
0782-jewels-and-stones
0835-linked-list-components
0870-magic-squares-in-grid
0906-walking-robot-simulation
0920-uncommon-words-from-two-sentences
0940-fruit-into-baskets
0952-word-subsets
0984-most-stones-removed-with-same-row-or-column
1147-flip-columns-for-maximum-number-of-equal-rows
1160-letter-tile-possibilities
1207-delete-nodes-and-return-forest
1218-lowest-common-ancestor-of-deepest-leaves
1227-number-of-equivalent-domino-pairs
1256-rank-transform-of-an-array
1294-range-frequency-queries
1353-find-resultant-array-after-removing-anagrams
1364-tuple-with-same-product
1387-find-elements-in-a-contaminated-binary-tree
1423-maximum-number-of-occurrences-of-a-substring
1460-number-of-substrings-containing-all-three-characters
1473-find-the-longest-substring-containing-vowels-in-even-counts
1500-count-largest-group
1502-construct-k-palindrome-strings
1620-check-if-array-pairs-are-divisible-by-k
1715-split-a-string-into-the-max-number-of-unique-substrings
1741-sort-array-by-increasing-frequency
1776-minimum-operations-to-reduce-x-to-zero
1786-count-the-number-of-consistent-strings
1915-check-if-one-string-swap-can-make-strings-equal
1995-finding-pairs-with-a-certain-sum
2034-minimum-absolute-difference-queries
2044-number-of-wonderful-substrings
2054-the-number-of-the-smallest-unoccupied-chair
2059-unique-length-3-palindromic-subsequences
2107-find-unique-binary-string
2204-find-subsequence-of-length-k-with-the-largest-sum
2215-finding-3-digit-even-numbers
2237-longest-palindrome-by-concatenating-two-letter-words
2240-intervals-between-identical-elements
2285-design-bitset
2289-minimum-operations-to-make-the-array-alternating
2300-construct-string-with-repeat-limit
2306-create-binary-tree-from-descriptions
2308-divide-array-into-equal-pairs
2356-largest-combination-with-bitwise-and-greater-than-zero
2434-design-a-number-container-system
2448-count-number-of-bad-pairs
2473-max-sum-of-a-pair-with-equal-sum-of-digits
2475-largest-palindromic-number
2483-task-scheduler-ii
2502-sort-the-people
2552-maximum-sum-of-distinct-subarrays-with-length-k
2581-divide-players-into-teams-of-equal-skill
2586-longest-square-streak-in-an-array
2599-take-k-of-each-character-from-left-and-right
2626-count-the-number-of-good-subarrays
2640-maximum-number-of-integers-to-choose-from-a-range-i
2677-cousins-in-binary-tree-ii
2685-first-completely-painted-row-or-column
2695-find-score-of-an-array-after-marking-all-elements
2707-merge-two-2d-arrays-by-summing-values
2755-extra-characters-in-a-string
2766-find-the-prefix-common-array-of-two-arrays
2778-frequency-tracker
2856-count-complete-subarrays-in-an-array
2888-minimum-index-of-a-valid-split
2915-count-of-interesting-subarrays
3227-find-missing-and-repeated-values
3228-maximum-size-of-a-set-after-removals
3242-count-elements-with-maximum-frequency
3267-find-longest-special-substring-that-occurs-thrice-i
3329-find-the-length-of-the-longest-common-prefix
3434-find-the-number-of-distinct-colors-among-the-balls
3445-lexicographically-minimum-string-after-removing-stars
3455-minimum-length-of-string-after-operations
3501-delete-nodes-from-linked-list-present-in-array
3621-minimum-operations-to-make-array-values-equal-to-k
3629-total-characters-in-string-after-transformations-i
3634-find-mirror-score-of-a-string
3656-minimum-number-of-operations-to-make-elements-in-array-distinct
3678-design-task-manager
3732-calculate-score-after-performing-instructions
3788-maximum-unique-subarray-sum-after-deletion
3934-coupon-code-validator

Tree

0101-symmetric-tree
0106-construct-binary-tree-from-inorder-and-postorder-traversal
0110-balanced-binary-tree
0112-path-sum
0113-path-sum-ii
0124-binary-tree-maximum-path-sum
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0199-binary-tree-right-side-view
0235-lowest-common-ancestor-of-a-binary-search-tree
0297-serialize-and-deserialize-binary-tree
0508-most-frequent-subtree-sum
0513-find-bottom-left-tree-value
0515-find-largest-value-in-each-tree-row
0543-diameter-of-binary-tree
0572-subtree-of-another-tree
0776-n-ary-tree-postorder-traversal
0988-flip-equivalent-binary-trees
0998-check-completeness-of-a-binary-tree
1035-cousins-in-binary-tree
1092-maximum-difference-between-node-and-ancestor
1207-delete-nodes-and-return-forest
1218-lowest-common-ancestor-of-deepest-leaves
1387-find-elements-in-a-contaminated-binary-tree
1450-delete-leaves-with-a-given-value
1474-longest-zigzag-path-in-a-binary-tree
1475-maximum-sum-bst-in-binary-tree
1484-linked-list-in-binary-tree
1653-number-of-good-leaf-nodes-pairs
2217-step-by-step-directions-from-a-binary-tree-node-to-another
2306-create-binary-tree-from-descriptions
2347-count-nodes-equal-to-average-of-subtree
2416-evaluate-boolean-binary-tree
2493-reverse-odd-levels-of-binary-tree
2545-height-of-binary-tree-after-subtree-removal-queries
2558-minimum-number-of-operations-to-sort-a-binary-tree-by-level
2567-closest-nodes-queries-in-a-binary-search-tree
2646-kth-largest-sum-in-a-binary-tree
2677-cousins-in-binary-tree-ii

Binary Tree

0101-symmetric-tree
0106-construct-binary-tree-from-inorder-and-postorder-traversal
0110-balanced-binary-tree
0112-path-sum
0113-path-sum-ii
0124-binary-tree-maximum-path-sum
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0199-binary-tree-right-side-view
0235-lowest-common-ancestor-of-a-binary-search-tree
0297-serialize-and-deserialize-binary-tree
0508-most-frequent-subtree-sum
0513-find-bottom-left-tree-value
0515-find-largest-value-in-each-tree-row
0543-diameter-of-binary-tree
0572-subtree-of-another-tree
0988-flip-equivalent-binary-trees
0998-check-completeness-of-a-binary-tree
1035-cousins-in-binary-tree
1092-maximum-difference-between-node-and-ancestor
1207-delete-nodes-and-return-forest
1218-lowest-common-ancestor-of-deepest-leaves
1387-find-elements-in-a-contaminated-binary-tree
1450-delete-leaves-with-a-given-value
1474-longest-zigzag-path-in-a-binary-tree
1475-maximum-sum-bst-in-binary-tree
1484-linked-list-in-binary-tree
1653-number-of-good-leaf-nodes-pairs
2217-step-by-step-directions-from-a-binary-tree-node-to-another
2306-create-binary-tree-from-descriptions
2347-count-nodes-equal-to-average-of-subtree
2416-evaluate-boolean-binary-tree
2493-reverse-odd-levels-of-binary-tree
2545-height-of-binary-tree-after-subtree-removal-queries
2558-minimum-number-of-operations-to-sort-a-binary-tree-by-level
2567-closest-nodes-queries-in-a-binary-search-tree
2646-kth-largest-sum-in-a-binary-tree
2677-cousins-in-binary-tree-ii

Database

0176-second-highest-salary
0184-department-highest-salary
0185-department-top-three-salaries
0196-delete-duplicate-emails
0570-managers-with-at-least-5-direct-reports
0585-investments-in-2016
0596-classes-more-than-5-students
0602-friend-requests-ii-who-has-the-most-friends
0610-triangle-judgement
0619-biggest-single-number
0627-swap-salary
1135-customers-who-bought-all-products
1155-product-sales-analysis-iii
1174-sales-analysis-iii
1317-monthly-transactions-i
1480-movie-rating
1523-capital-gainloss
1724-customer-who-visited-but-did-not-make-any-transactions
1811-fix-names-in-a-table
1877-find-followers-count
1882-the-number-of-employees-which-report-to-each-employee
1942-primary-department-for-each-employee
2127-employees-whose-manager-left-the-company

String

0005-longest-palindromic-substring
0014-longest-common-prefix
0020-valid-parentheses
0028-find-the-index-of-the-first-occurrence-in-a-string
0044-wildcard-matching
0049-group-anagrams
0067-add-binary
0071-simplify-path
0072-edit-distance
0079-word-search
0115-distinct-subsequences
0139-word-break
0165-compare-version-numbers
0179-largest-number
0205-isomorphic-strings
0208-implement-trie-prefix-tree
0211-design-add-and-search-words-data-structure
0212-word-search-ii
0214-shortest-palindrome
0242-valid-anagram
0297-serialize-and-deserialize-binary-tree
0301-remove-invalid-parentheses
0383-ransom-note
0394-decode-string
0415-add-strings
0424-longest-repeating-character-replacement
0433-minimum-genetic-mutation
0438-find-all-anagrams-in-a-string
0459-repeated-substring-pattern
0474-ones-and-zeroes
0539-minimum-time-difference
0556-next-greater-element-iii
0567-permutation-in-string
0583-delete-operation-for-two-strings
0592-fraction-addition-and-subtraction
0691-stickers-to-spell-word
0696-count-binary-substrings
0742-to-lower-case
0768-partition-labels
0782-jewels-and-stones
0800-letter-case-permutation
0812-rotate-string
0920-uncommon-words-from-two-sentences
0952-word-subsets
0957-minimum-add-to-make-parentheses-valid
0962-flip-string-to-monotone-increasing
1160-letter-tile-possibilities
1250-longest-common-subsequence
1252-break-a-palindrome
1302-delete-characters-to-make-fancy-string
1304-longest-happy-string
1350-remove-sub-folders-from-the-filesystem
1353-find-resultant-array-after-removing-anagrams
1423-maximum-number-of-occurrences-of-a-substring
1460-number-of-substrings-containing-all-three-characters
1473-find-the-longest-substring-containing-vowels-in-even-counts
1502-construct-k-palindrome-strings
1508-longest-happy-prefix
1516-the-k-th-lexicographical-string-of-all-happy-strings-of-length-n
1524-string-matching-in-an-array
1537-maximum-score-after-splitting-a-string
1566-check-if-a-word-occurs-as-a-prefix-of-any-word-in-a-sentence
1715-split-a-string-into-the-max-number-of-unique-substrings
1744-number-of-ways-to-form-a-target-string-given-a-dictionary
1786-count-the-number-of-consistent-strings
1818-maximum-score-from-removing-substrings
1871-palindrome-partitioning-iv
1884-minimum-changes-to-make-alternating-binary-string
1895-minimum-number-of-operations-to-move-all-balls-to-each-box
1915-check-if-one-string-swap-can-make-strings-equal
1923-sentence-similarity-iii
2021-remove-all-occurrences-of-a-substring
2044-number-of-wonderful-substrings
2059-unique-length-3-palindromic-subsequences
2076-sum-of-digits-of-string-after-convert
2095-minimum-number-of-swaps-to-make-the-string-balanced
2107-find-unique-binary-string
2217-step-by-step-directions-from-a-binary-tree-node-to-another
2219-maximum-number-of-words-found-in-sentences
2221-check-if-a-parentheses-string-can-be-valid
2232-adding-spaces-to-a-string
2237-longest-palindrome-by-concatenating-two-letter-words
2260-divide-a-string-into-groups-of-size-k
2285-design-bitset
2292-counting-words-with-a-given-prefix
2300-construct-string-with-repeat-limit
2346-largest-3-same-digit-number-in-string
2414-move-pieces-to-obtain-a-string
2463-minimum-recolors-to-get-k-consecutive-black-blocks
2475-largest-palindromic-number
2494-sum-of-prefix-scores-of-strings
2502-sort-the-people
2580-circular-sentence
2599-take-k-of-each-character-from-left-and-right
2691-count-vowel-strings-in-ranges
2727-number-of-senior-citizens
2755-extra-characters-in-a-string
2800-minimum-string-length-after-removing-substrings
3018-make-string-a-subsequence-using-cyclic-increments
3142-longest-unequal-adjacent-groups-subsequence-ii
3143-longest-unequal-adjacent-groups-subsequence-i
3174-minimum-number-of-changes-to-make-binary-string-beautiful
3194-find-words-containing-character
3195-separate-black-and-white-balls
3267-find-longest-special-substring-that-occurs-thrice-i
3309-count-prefix-and-suffix-pairs-i
3329-find-the-length-of-the-longest-common-prefix
3396-valid-word
3445-lexicographically-minimum-string-after-removing-stars
3447-clear-digits
3451-string-compression-iii
3455-minimum-length-of-string-after-operations
3617-find-the-original-typed-string-i
3629-total-characters-in-string-after-transformations-i
3634-find-mirror-score-of-a-string
3683-find-the-lexicographically-largest-string-from-the-box-i
3732-calculate-score-after-performing-instructions
3812-smallest-palindromic-rearrangement-i
3931-process-string-with-special-operations-i
3934-coupon-code-validator

Depth-First Search

0101-symmetric-tree
0110-balanced-binary-tree
0112-path-sum
0113-path-sum-ii
0124-binary-tree-maximum-path-sum
0130-surrounded-regions
0133-clone-graph
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0199-binary-tree-right-side-view
0211-design-add-and-search-words-data-structure
0235-lowest-common-ancestor-of-a-binary-search-tree
0297-serialize-and-deserialize-binary-tree
0386-lexicographical-numbers
0508-most-frequent-subtree-sum
0513-find-bottom-left-tree-value
0515-find-largest-value-in-each-tree-row
0543-diameter-of-binary-tree
0572-subtree-of-another-tree
0684-redundant-connection
0776-n-ary-tree-postorder-traversal
0794-swim-in-rising-water
0971-shortest-bridge
0984-most-stones-removed-with-same-row-or-column
0988-flip-equivalent-binary-trees
1035-cousins-in-binary-tree
1092-maximum-difference-between-node-and-ancestor
1207-delete-nodes-and-return-forest
1218-lowest-common-ancestor-of-deepest-leaves
1350-remove-sub-folders-from-the-filesystem
1387-find-elements-in-a-contaminated-binary-tree
1396-count-servers-that-communicate
1450-delete-leaves-with-a-given-value
1474-longest-zigzag-path-in-a-binary-tree
1475-maximum-sum-bst-in-binary-tree
1484-linked-list-in-binary-tree
1653-number-of-good-leaf-nodes-pairs
2035-count-sub-islands
2217-step-by-step-directions-from-a-binary-tree-node-to-another
2347-count-nodes-equal-to-average-of-subtree
2416-evaluate-boolean-binary-tree
2438-find-closest-node-to-given-two-nodes
2493-reverse-odd-levels-of-binary-tree
2545-height-of-binary-tree-after-subtree-removal-queries
2567-closest-nodes-queries-in-a-binary-search-tree
2677-cousins-in-binary-tree-ii
2793-count-the-number-of-complete-components

Dynamic Programming

0005-longest-palindromic-substring
0044-wildcard-matching
0045-jump-game-ii
0062-unique-paths
0072-edit-distance
0085-maximal-rectangle
0115-distinct-subsequences
0118-pascals-triangle
0120-triangle
0124-binary-tree-maximum-path-sum
0139-word-break
0300-longest-increasing-subsequence
0312-burst-balloons
0322-coin-change
0338-counting-bits
0343-integer-break
0368-largest-divisible-subset
0376-wiggle-subsequence
0377-combination-sum-iv
0410-split-array-largest-sum
0413-arithmetic-slices
0416-partition-equal-subset-sum
0435-non-overlapping-intervals
0474-ones-and-zeroes
0494-target-sum
0518-coin-change-ii
0583-delete-operation-for-two-strings
0600-non-negative-integers-without-consecutive-ones
0650-2-keys-keyboard
0688-knight-probability-in-chessboard
0691-stickers-to-spell-word
0747-min-cost-climbing-stairs
0806-domino-and-tromino-tiling
0962-flip-string-to-monotone-increasing
0972-knight-dialer
1025-minimum-cost-for-tickets
1063-best-sightseeing-pair
1096-maximum-sum-of-two-non-overlapping-subarrays
1250-longest-common-subsequence
1352-maximum-profit-in-job-scheduling
1402-count-square-submatrices-with-all-ones
1456-find-the-city-with-the-smallest-number-of-neighbors-at-a-threshold-distance
1474-longest-zigzag-path-in-a-binary-tree
1475-maximum-sum-bst-in-binary-tree
1511-count-number-of-teams
1586-longest-subarray-of-1s-after-deleting-one-element
1628-count-submatrices-with-all-ones
1744-number-of-ways-to-form-a-target-string-given-a-dictionary
1757-minimum-jumps-to-reach-home
1761-count-sorted-vowel-strings
1766-minimum-number-of-removals-to-make-mountain-array
1849-maximum-absolute-sum-of-any-subarray
1851-maximum-number-of-events-that-can-be-attended-ii
1871-palindrome-partitioning-iv
2164-two-best-non-overlapping-events
2262-solving-questions-with-brainpower
2554-minimum-total-distance-traveled
2562-count-ways-to-build-good-strings
2586-longest-square-streak-in-an-array
2755-extra-characters-in-a-string
2794-maximum-number-of-moves-in-a-grid
2808-painting-the-walls
3142-longest-unequal-adjacent-groups-subsequence-ii
3143-longest-unequal-adjacent-groups-subsequence-i
3209-minimum-number-of-coins-for-fruits
3239-minimum-number-of-operations-to-make-x-and-y-equal
3490-find-the-maximum-length-of-valid-subsequence-i
3491-find-the-maximum-length-of-valid-subsequence-ii
3629-total-characters-in-string-after-transformations-i

Math

0002-add-two-numbers
0050-powx-n
0062-unique-paths
0066-plus-one
0067-add-binary
0069-sqrtx
0326-power-of-three
0343-integer-break
0367-valid-perfect-square
0368-largest-divisible-subset
0371-sum-of-two-integers
0415-add-strings
0447-number-of-boomerangs
0539-minimum-time-difference
0556-next-greater-element-iii
0592-fraction-addition-and-subtraction
0628-maximum-product-of-three-numbers
0650-2-keys-keyboard
0668-kth-smallest-number-in-multiplication-table
0670-maximum-swap
0870-magic-squares-in-grid
1279-prime-arrangements
1411-convert-binary-number-in-a-linked-list-to-integer
1421-find-numbers-with-even-number-of-digits
1426-find-n-unique-integers-sum-up-to-zero
1440-convert-integer-to-the-sum-of-two-no-zero-integers
1477-product-of-the-last-k-numbers
1500-count-largest-group
1515-find-the-minimum-number-of-fibonacci-numbers-whose-sum-is-k
1529-max-difference-you-can-get-from-changing-an-integer
1642-water-bottles
1761-count-sorted-vowel-strings
1889-check-if-number-is-a-sum-of-powers-of-three
1993-sum-of-all-subset-xor-totals
2155-find-missing-observations
2160-minimum-operations-to-make-a-uni-value-grid
2437-maximum-number-of-groups-entering-a-competition
2448-count-number-of-bad-pairs
2575-minimum-cuts-to-divide-a-circle
2595-smallest-value-after-replacing-with-sum-of-prime-factors
2610-closest-prime-numbers-in-range
2802-find-the-punishment-number-of-an-integer
2903-insert-greatest-common-divisors-in-linked-list
2998-count-symmetric-integers
3172-divisible-and-non-divisible-sums-difference
3227-find-missing-and-repeated-values
3278-find-the-number-of-ways-to-place-people-i
3321-type-of-triangle
3336-water-bottles-ii
3555-final-array-state-after-k-multiplication-operations-i
3600-find-the-k-th-character-in-string-game-i
3629-total-characters-in-string-after-transformations-i
3702-maximum-subarray-with-equal-products
3830-find-closest-person

Greedy

0044-wildcard-matching
0045-jump-game-ii
0135-candy
0179-largest-number
0324-wiggle-sort-ii
0376-wiggle-subsequence
0410-split-array-largest-sum
0435-non-overlapping-intervals
0605-can-place-flowers
0621-task-scheduler
0624-maximum-distance-in-arrays
0670-maximum-swap
0768-partition-labels
0780-max-chunks-to-make-sorted
0957-minimum-add-to-make-parentheses-valid
1049-minimum-domino-rotations-for-equal-row
1252-break-a-palindrome
1304-longest-happy-string
1502-construct-k-palindrome-strings
1515-find-the-minimum-number-of-fibonacci-numbers-whose-sum-is-k
1529-max-difference-you-can-get-from-changing-an-integer
1711-find-valid-matrix-given-row-and-column-sums
1762-furthest-building-you-can-reach
1766-minimum-number-of-removals-to-make-mountain-array
1818-maximum-score-from-removing-substrings
1917-maximum-average-pass-ratio
1929-maximum-value-at-a-given-index-in-a-bounded-array
2026-merge-triplets-to-form-target-triplet
2089-maximum-matrix-sum
2095-minimum-number-of-swaps-to-make-the-string-balanced
2221-check-if-a-parentheses-string-can-be-valid
2237-longest-palindrome-by-concatenating-two-letter-words
2289-minimum-operations-to-make-the-array-alternating
2300-construct-string-with-repeat-limit
2387-partition-array-such-that-maximum-difference-is-k
2437-maximum-number-of-groups-entering-a-competition
2475-largest-palindromic-number
2488-divide-intervals-into-minimum-number-of-groups
2497-maximum-matching-of-players-with-trainers
2509-minimize-xor
2600-maximum-tastiness-of-candy-basket
2616-maximal-score-after-applying-k-operations
2636-maximum-subsequence-score
2640-maximum-number-of-integers-to-choose-from-a-range-i
2720-minimize-the-maximum-difference-of-pairs
3143-longest-unequal-adjacent-groups-subsequence-i
3171-minimum-equal-sum-of-two-arrays-after-replacing-zeros
3195-separate-black-and-white-balls
3228-maximum-size-of-a-set-after-removals
3231-minimum-number-of-coins-to-be-added
3241-divide-array-into-arrays-with-max-difference
3445-lexicographically-minimum-string-after-removing-stars
3738-make-array-non-decreasing
3743-reschedule-meetings-for-maximum-free-time-i
3788-maximum-unique-subarray-sum-after-deletion

Matrix

0036-valid-sudoku
0073-set-matrix-zeroes
0074-search-a-2d-matrix
0079-word-search
0085-maximal-rectangle
0130-surrounded-regions
0212-word-search-ii
0378-kth-smallest-element-in-a-sorted-matrix
0498-diagonal-traverse
0794-swim-in-rising-water
0870-magic-squares-in-grid
0971-shortest-bridge
1036-rotting-oranges
1147-flip-columns-for-maximum-number-of-equal-rows
1242-matrix-block-sum
1396-count-servers-that-communicate
1402-count-square-submatrices-with-all-ones
1496-lucky-numbers-in-a-matrix
1628-count-submatrices-with-all-ones
1711-find-valid-matrix-given-row-and-column-sums
1876-map-of-highest-peak
1972-rotating-the-box
2035-count-sub-islands
2089-maximum-matrix-sum
2132-convert-1d-array-into-2d-array
2145-grid-game
2160-minimum-operations-to-make-a-uni-value-grid
2343-count-unguarded-cells-in-the-grid
2411-spiral-matrix-iv
2685-first-completely-painted-row-or-column
2711-minimum-time-to-visit-a-cell-in-a-grid
2794-maximum-number-of-moves-in-a-grid
3031-construct-product-matrix
3227-find-missing-and-repeated-values
3627-find-minimum-time-to-reach-last-room-i
3628-find-minimum-time-to-reach-last-room-ii

Simulation

0067-add-binary
0415-add-strings
0498-diagonal-traverse
0592-fraction-addition-and-subtraction
0906-walking-robot-simulation
1310-watering-plants
1642-water-bottles
2006-find-the-student-that-will-replace-the-chalk
2021-remove-all-occurrences-of-a-substring
2048-build-array-from-permutation
2076-sum-of-digits-of-string-after-convert
2132-convert-1d-array-into-2d-array
2155-find-missing-observations
2232-adding-spaces-to-a-string
2260-divide-a-string-into-groups-of-size-k
2265-partition-array-according-to-given-pivot
2343-count-unguarded-cells-in-the-grid
2411-spiral-matrix-iv
2483-task-scheduler-ii
2551-apply-operations-to-an-array
2595-smallest-value-after-replacing-with-sum-of-prime-factors
2692-take-gifts-from-the-richest-pile
2695-find-score-of-an-array-after-marking-all-elements
2800-minimum-string-length-after-removing-substrings
3332-minimum-operations-to-exceed-threshold-value-ii
3336-water-bottles-ii
3434-find-the-number-of-distinct-colors-among-the-balls
3447-clear-digits
3555-final-array-state-after-k-multiplication-operations-i
3600-find-the-k-th-character-in-string-game-i
3634-find-mirror-score-of-a-string
3732-calculate-score-after-performing-instructions
3790-fruits-into-baskets-ii
3931-process-string-with-special-operations-i

Stack

0020-valid-parentheses
0071-simplify-path
0084-largest-rectangle-in-histogram
0085-maximal-rectangle
0143-reorder-list
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0225-implement-stack-using-queues
0394-decode-string
0776-n-ary-tree-postorder-traversal
0780-max-chunks-to-make-sorted
0957-minimum-add-to-make-parentheses-valid
1002-maximum-width-ramp
1497-design-a-stack-with-increment-operation
1570-final-prices-with-a-special-discount-in-a-shop
1628-count-submatrices-with-all-ones
1679-shortest-subarray-to-be-removed-to-make-array-sorted
1818-maximum-score-from-removing-substrings
2021-remove-all-occurrences-of-a-substring
2095-minimum-number-of-swaps-to-make-the-string-balanced
2221-check-if-a-parentheses-string-can-be-valid
2800-minimum-string-length-after-removing-substrings
3445-lexicographically-minimum-string-after-removing-stars
3447-clear-digits
3634-find-mirror-score-of-a-string
3738-make-array-non-decreasing

Monotonic Stack

0084-largest-rectangle-in-histogram
0085-maximal-rectangle
0780-max-chunks-to-make-sorted
1002-maximum-width-ramp
1570-final-prices-with-a-special-discount-in-a-shop
1628-count-submatrices-with-all-ones
1679-shortest-subarray-to-be-removed-to-make-array-sorted
3738-make-array-non-decreasing

Sorting

0015-3sum
0016-3sum-closest
0049-group-anagrams
0075-sort-colors
0169-majority-element
0179-largest-number
0217-contains-duplicate
0229-majority-element-ii
0242-valid-anagram
0295-find-median-from-data-stream
0324-wiggle-sort-ii
0347-top-k-frequent-elements
0368-largest-divisible-subset
0378-kth-smallest-element-in-a-sorted-matrix
0435-non-overlapping-intervals
0436-find-right-interval
0539-minimum-time-difference
0594-longest-harmonious-subsequence
0621-task-scheduler
0628-maximum-product-of-three-numbers
0719-find-k-th-smallest-pair-distance
0780-max-chunks-to-make-sorted
0948-sort-an-array
1256-rank-transform-of-an-array
1333-sort-the-jumbled-numbers
1352-maximum-profit-in-job-scheduling
1353-find-resultant-array-after-removing-anagrams
1615-range-sum-of-sorted-subarray-sums
1741-sort-array-by-increasing-frequency
1851-maximum-number-of-events-that-can-be-attended-ii
1962-single-threaded-cpu
2160-minimum-operations-to-make-a-uni-value-grid
2164-two-best-non-overlapping-events
2179-most-beautiful-item-for-each-query
2204-find-subsequence-of-length-k-with-the-largest-sum
2215-finding-3-digit-even-numbers
2387-partition-array-such-that-maximum-difference-is-k
2473-max-sum-of-a-pair-with-equal-sum-of-digits
2488-divide-intervals-into-minimum-number-of-groups
2497-maximum-matching-of-players-with-trainers
2502-sort-the-people
2554-minimum-total-distance-traveled
2581-divide-players-into-teams-of-equal-skill
2586-longest-square-streak-in-an-array
2600-maximum-tastiness-of-candy-basket
2636-maximum-subsequence-score
2640-maximum-number-of-integers-to-choose-from-a-range-i
2646-kth-largest-sum-in-a-binary-tree
2695-find-score-of-an-array-after-marking-all-elements
2699-count-the-number-of-fair-pairs
2888-minimum-index-of-a-valid-split
2891-maximum-beauty-of-an-array-after-applying-operation
3231-minimum-number-of-coins-to-be-added
3241-divide-array-into-arrays-with-max-difference
3278-find-the-number-of-ways-to-place-people-i
3291-find-if-array-can-be-sorted
3321-type-of-triangle
3430-count-days-without-meetings
3812-smallest-palindromic-rearrangement-i
3934-coupon-code-validator

Union Find

0128-longest-consecutive-sequence
0130-surrounded-regions
0684-redundant-connection
0794-swim-in-rising-water
0984-most-stones-removed-with-same-row-or-column
1396-count-servers-that-communicate
2035-count-sub-islands
2793-count-the-number-of-complete-components

Binary Search

0034-find-first-and-last-position-of-element-in-sorted-array
0035-search-insert-position
0069-sqrtx
0074-search-a-2d-matrix
0153-find-minimum-in-rotated-sorted-array
0154-find-minimum-in-rotated-sorted-array-ii
0167-two-sum-ii-input-array-is-sorted
0209-minimum-size-subarray-sum
0300-longest-increasing-subsequence
0367-valid-perfect-square
0378-kth-smallest-element-in-a-sorted-matrix
0410-split-array-largest-sum
0436-find-right-interval
0493-reverse-pairs
0668-kth-smallest-number-in-multiplication-table
0719-find-k-th-smallest-pair-distance
0729-my-calendar-i
0731-my-calendar-ii
0732-my-calendar-iii
0794-swim-in-rising-water
0882-peak-index-in-a-mountain-array
1294-range-frequency-queries
1335-maximum-candies-allocated-to-k-children
1352-maximum-profit-in-job-scheduling
1615-range-sum-of-sorted-subarray-sums
1646-kth-missing-positive-number
1679-shortest-subarray-to-be-removed-to-make-array-sorted
1766-minimum-number-of-removals-to-make-mountain-array
1776-minimum-operations-to-reduce-x-to-zero
1851-maximum-number-of-events-that-can-be-attended-ii
1886-minimum-limit-of-balls-in-a-bag
1929-maximum-value-at-a-given-index-in-a-bounded-array
2006-find-the-student-that-will-replace-the-chalk
2164-two-best-non-overlapping-events
2179-most-beautiful-item-for-each-query
2188-minimized-maximum-of-products-distributed-to-any-store
2294-minimum-time-to-complete-trips
2394-count-subarrays-with-score-less-than-k
2437-maximum-number-of-groups-entering-a-competition
2498-smallest-subarrays-with-maximum-bitwise-or
2567-closest-nodes-queries-in-a-binary-search-tree
2586-longest-square-streak-in-an-array
2600-maximum-tastiness-of-candy-basket
2614-maximum-count-of-positive-integer-and-negative-integer
2640-maximum-number-of-integers-to-choose-from-a-range-i
2665-minimum-time-to-repair-cars
2673-maximize-win-from-two-segments
2699-count-the-number-of-fair-pairs
2720-minimize-the-maximum-difference-of-pairs
2891-maximum-beauty-of-an-array-after-applying-operation
3267-find-longest-special-substring-that-occurs-thrice-i
3643-zero-array-transformation-ii
3790-fruits-into-baskets-ii

Design

0146-lru-cache
0208-implement-trie-prefix-tree
0211-design-add-and-search-words-data-structure
0225-implement-stack-using-queues
0295-find-median-from-data-stream
0297-serialize-and-deserialize-binary-tree
0460-lfu-cache
0729-my-calendar-i
0731-my-calendar-ii
0732-my-calendar-iii
0859-design-circular-deque
0860-design-circular-queue
1294-range-frequency-queries
1387-find-elements-in-a-contaminated-binary-tree
1477-product-of-the-last-k-numbers
1497-design-a-stack-with-increment-operation
1995-finding-pairs-with-a-certain-sum
2285-design-bitset
2434-design-a-number-container-system
2778-frequency-tracker
3678-design-task-manager

Segment Tree

0493-reverse-pairs
0729-my-calendar-i
0731-my-calendar-ii
0732-my-calendar-iii
1294-range-frequency-queries
3790-fruits-into-baskets-ii

Divide and Conquer

0023-merge-k-sorted-lists
0106-construct-binary-tree-from-inorder-and-postorder-traversal
0169-majority-element
0324-wiggle-sort-ii
0347-top-k-frequent-elements
0493-reverse-pairs
0948-sort-an-array

Binary Indexed Tree

0493-reverse-pairs
1511-count-number-of-teams

Merge Sort

0023-merge-k-sorted-lists
0493-reverse-pairs
0948-sort-an-array

Ordered Set

0493-reverse-pairs
0729-my-calendar-i
0731-my-calendar-ii
0732-my-calendar-iii
2434-design-a-number-container-system
2868-continuous-subarrays
3678-design-task-manager
3790-fruits-into-baskets-ii

Two Pointers

0005-longest-palindromic-substring
0015-3sum
0016-3sum-closest
0019-remove-nth-node-from-end-of-list
0028-find-the-index-of-the-first-occurrence-in-a-string
0031-next-permutation
0061-rotate-list
0075-sort-colors
0141-linked-list-cycle
0143-reorder-list
0165-compare-version-numbers
0167-two-sum-ii-input-array-is-sorted
0295-find-median-from-data-stream
0556-next-greater-element-iii
0567-permutation-in-string
0696-count-binary-substrings
0719-find-k-th-smallest-pair-distance
0768-partition-labels
0811-number-of-subarrays-with-bounded-maximum
1566-check-if-a-word-occurs-as-a-prefix-of-any-word-in-a-sentence
1615-range-sum-of-sorted-subarray-sums
1679-shortest-subarray-to-be-removed-to-make-array-sorted
1923-sentence-similarity-iii
1972-rotating-the-box
2095-minimum-number-of-swaps-to-make-the-string-balanced
2232-adding-spaces-to-a-string
2265-partition-array-according-to-given-pivot
2320-find-all-k-distant-indices-in-an-array
2414-move-pieces-to-obtain-a-string
2488-divide-intervals-into-minimum-number-of-groups
2497-maximum-matching-of-players-with-trainers
2551-apply-operations-to-an-array
2581-divide-players-into-teams-of-equal-skill
2699-count-the-number-of-fair-pairs
2707-merge-two-2d-arrays-by-summing-values
3018-make-string-a-subsequence-using-cyclic-increments
3195-separate-black-and-white-balls
3683-find-the-lexicographically-largest-string-from-the-box-i

String Matching

0028-find-the-index-of-the-first-occurrence-in-a-string
0214-shortest-palindrome
0459-repeated-substring-pattern
0572-subtree-of-another-tree
0812-rotate-string
1508-longest-happy-prefix
1524-string-matching-in-an-array
1566-check-if-a-word-occurs-as-a-prefix-of-any-word-in-a-sentence
2292-counting-words-with-a-given-prefix
3309-count-prefix-and-suffix-pairs-i

Heap (Priority Queue)

0023-merge-k-sorted-lists
0295-find-median-from-data-stream
0347-top-k-frequent-elements
0373-find-k-pairs-with-smallest-sums
0378-kth-smallest-element-in-a-sorted-matrix
0621-task-scheduler
0794-swim-in-rising-water
0948-sort-an-array
1304-longest-happy-string
1325-path-with-maximum-probability
1762-furthest-building-you-can-reach
1917-maximum-average-pass-ratio
1962-single-threaded-cpu
2054-the-number-of-the-smallest-unoccupied-chair
2164-two-best-non-overlapping-events
2204-find-subsequence-of-length-k-with-the-largest-sum
2300-construct-string-with-repeat-limit
2434-design-a-number-container-system
2473-max-sum-of-a-pair-with-equal-sum-of-digits
2488-divide-intervals-into-minimum-number-of-groups
2616-maximal-score-after-applying-k-operations
2636-maximum-subsequence-score
2692-take-gifts-from-the-richest-pile
2695-find-score-of-an-array-after-marking-all-elements
2711-minimum-time-to-visit-a-cell-in-a-grid
2868-continuous-subarrays
3209-minimum-number-of-coins-for-fruits
3332-minimum-operations-to-exceed-threshold-value-ii
3445-lexicographically-minimum-string-after-removing-stars
3555-final-array-state-after-k-multiplication-operations-i
3627-find-minimum-time-to-reach-last-room-i
3628-find-minimum-time-to-reach-last-room-ii
3678-design-task-manager

Bucket Sort

0347-top-k-frequent-elements
0948-sort-an-array

Radix Sort

0948-sort-an-array

Counting Sort

0169-majority-element
0229-majority-element-ii
0347-top-k-frequent-elements
0383-ransom-note
0594-longest-harmonious-subsequence
0621-task-scheduler
0920-uncommon-words-from-two-sentences
0948-sort-an-array
1160-letter-tile-possibilities
1227-number-of-equivalent-domino-pairs
1364-tuple-with-same-product
1396-count-servers-that-communicate
1502-construct-k-palindrome-strings
1620-check-if-array-pairs-are-divisible-by-k
1786-count-the-number-of-consistent-strings
1915-check-if-one-string-swap-can-make-strings-equal
2237-longest-palindrome-by-concatenating-two-letter-words
2289-minimum-operations-to-make-the-array-alternating
2300-construct-string-with-repeat-limit
2308-divide-array-into-equal-pairs
2356-largest-combination-with-bitwise-and-greater-than-zero
2448-count-number-of-bad-pairs
2475-largest-palindromic-number
2494-sum-of-prefix-scores-of-strings
2614-maximum-count-of-positive-integer-and-negative-integer
3242-count-elements-with-maximum-frequency
3267-find-longest-special-substring-that-occurs-thrice-i
3455-minimum-length-of-string-after-operations
3629-total-characters-in-string-after-transformations-i
3812-smallest-palindromic-rearrangement-i

Graph

0133-clone-graph
0684-redundant-connection
0984-most-stones-removed-with-same-row-or-column
1325-path-with-maximum-probability
1456-find-the-city-with-the-smallest-number-of-neighbors-at-a-threshold-distance
2438-find-closest-node-to-given-two-nodes
2711-minimum-time-to-visit-a-cell-in-a-grid
2793-count-the-number-of-complete-components
3189-find-champion-ii
3517-shortest-distance-after-road-addition-queries-i
3627-find-minimum-time-to-reach-last-room-i
3628-find-minimum-time-to-reach-last-room-ii

Shortest Path

1325-path-with-maximum-probability
1456-find-the-city-with-the-smallest-number-of-neighbors-at-a-threshold-distance
2711-minimum-time-to-visit-a-cell-in-a-grid
3627-find-minimum-time-to-reach-last-room-i
3628-find-minimum-time-to-reach-last-room-ii

Linked List

0002-add-two-numbers
0019-remove-nth-node-from-end-of-list
0023-merge-k-sorted-lists
0025-reverse-nodes-in-k-group
0061-rotate-list
0083-remove-duplicates-from-sorted-list
0138-copy-list-with-random-pointer
0141-linked-list-cycle
0143-reorder-list
0146-lru-cache
0460-lfu-cache
0725-split-linked-list-in-parts
0835-linked-list-components
0859-design-circular-deque
0860-design-circular-queue
1411-convert-binary-number-in-a-linked-list-to-integer
1484-linked-list-in-binary-tree
2411-spiral-matrix-iv
2903-insert-greatest-common-divisors-in-linked-list
3501-delete-nodes-from-linked-list-present-in-array

Breadth-First Search

0101-symmetric-tree
0112-path-sum
0130-surrounded-regions
0133-clone-graph
0199-binary-tree-right-side-view
0297-serialize-and-deserialize-binary-tree
0301-remove-invalid-parentheses
0322-coin-change
0433-minimum-genetic-mutation
0513-find-bottom-left-tree-value
0515-find-largest-value-in-each-tree-row
0684-redundant-connection
0794-swim-in-rising-water
0971-shortest-bridge
0998-check-completeness-of-a-binary-tree
1035-cousins-in-binary-tree
1036-rotting-oranges
1218-lowest-common-ancestor-of-deepest-leaves
1387-find-elements-in-a-contaminated-binary-tree
1396-count-servers-that-communicate
1484-linked-list-in-binary-tree
1757-minimum-jumps-to-reach-home
1876-map-of-highest-peak
2035-count-sub-islands
2493-reverse-odd-levels-of-binary-tree
2545-height-of-binary-tree-after-subtree-removal-queries
2558-minimum-number-of-operations-to-sort-a-binary-tree-by-level
2646-kth-largest-sum-in-a-binary-tree
2677-cousins-in-binary-tree-ii
2711-minimum-time-to-visit-a-cell-in-a-grid
2793-count-the-number-of-complete-components
3239-minimum-number-of-operations-to-make-x-and-y-equal
3517-shortest-distance-after-road-addition-queries-i

Recursion

0002-add-two-numbers
0025-reverse-nodes-in-k-group
0044-wildcard-matching
0050-powx-n
0143-reorder-list
0326-power-of-three
0394-decode-string
3600-find-the-k-th-character-in-string-game-i

Bit Manipulation

0067-add-binary
0078-subsets
0137-single-number-ii
0260-single-number-iii
0338-counting-bits
0371-sum-of-two-integers
0421-maximum-xor-of-two-numbers-in-an-array
0476-number-complement
0691-stickers-to-spell-word
0800-letter-case-permutation
1435-xor-queries-of-a-subarray
1441-minimum-flips-to-make-a-or-b-equal-to-c
1473-find-the-longest-substring-containing-vowels-in-even-counts
1786-count-the-number-of-consistent-strings
1940-maximum-xor-for-each-query
1993-sum-of-all-subset-xor-totals
2044-number-of-wonderful-substrings
2059-unique-length-3-palindromic-subsequences
2170-count-number-of-maximum-bitwise-or-subsets
2308-divide-array-into-equal-pairs
2323-minimum-bit-flips-to-convert-number
2356-largest-combination-with-bitwise-and-greater-than-zero
2478-longest-nice-subarray
2498-smallest-subarrays-with-maximum-bitwise-or
2503-longest-subarray-with-maximum-bitwise-and
2509-minimize-xor
2533-bitwise-xor-of-all-pairings
2766-find-the-prefix-common-array-of-two-arrays
2792-neighboring-bitwise-xor
3291-find-if-array-can-be-sorted
3380-shortest-subarray-with-or-at-least-k-ii
3394-minimum-array-end
3475-minimum-operations-to-make-binary-array-elements-equal-to-one-i
3600-find-the-k-th-character-in-string-game-i

Trie

0014-longest-common-prefix
0139-word-break
0208-implement-trie-prefix-tree
0211-design-add-and-search-words-data-structure
0212-word-search-ii
0386-lexicographical-numbers
0421-maximum-xor-of-two-numbers-in-an-array
1350-remove-sub-folders-from-the-filesystem
2494-sum-of-prefix-scores-of-strings
2755-extra-characters-in-a-string
3309-count-prefix-and-suffix-pairs-i
3329-find-the-length-of-the-longest-common-prefix

Sliding Window

0209-minimum-size-subarray-sum
0219-contains-duplicate-ii
0424-longest-repeating-character-replacement
0438-find-all-anagrams-in-a-string
0567-permutation-in-string
0594-longest-harmonious-subsequence
0940-fruit-into-baskets
1096-maximum-sum-of-two-non-overlapping-subarrays
1423-maximum-number-of-occurrences-of-a-substring
1460-number-of-substrings-containing-all-three-characters
1586-longest-subarray-of-1s-after-deleting-one-element
1755-defuse-the-bomb
1776-minimum-operations-to-reduce-x-to-zero
2255-minimum-swaps-to-group-all-1s-together-ii
2394-count-subarrays-with-score-less-than-k
2463-minimum-recolors-to-get-k-consecutive-black-blocks
2478-longest-nice-subarray
2498-smallest-subarrays-with-maximum-bitwise-or
2552-maximum-sum-of-distinct-subarrays-with-length-k
2599-take-k-of-each-character-from-left-and-right
2626-count-the-number-of-good-subarrays
2673-maximize-win-from-two-segments
2856-count-complete-subarrays-in-an-array
2868-continuous-subarrays
2891-maximum-beauty-of-an-array-after-applying-operation
3213-count-subarrays-where-max-element-appears-at-least-k-times
3267-find-longest-special-substring-that-occurs-thrice-i
3380-shortest-subarray-with-or-at-least-k-ii
3475-minimum-operations-to-make-binary-array-elements-equal-to-one-i
3483-alternating-groups-ii
3522-find-the-power-of-k-size-subarrays-i
3702-maximum-subarray-with-equal-products
3743-reschedule-meetings-for-maximum-free-time-i

Memoization

0139-word-break
3239-minimum-number-of-operations-to-make-x-and-y-equal

Prefix Sum

0209-minimum-size-subarray-sum
0238-product-of-array-except-self
0410-split-array-largest-sum
0525-contiguous-array
0560-subarray-sum-equals-k
0731-my-calendar-ii
0732-my-calendar-iii
1242-matrix-block-sum
1435-xor-queries-of-a-subarray
1473-find-the-longest-substring-containing-vowels-in-even-counts
1477-product-of-the-last-k-numbers
1537-maximum-score-after-splitting-a-string
1603-running-sum-of-1d-array
1776-minimum-operations-to-reduce-x-to-zero
1895-minimum-number-of-operations-to-move-all-balls-to-each-box
1940-maximum-xor-for-each-query
2006-find-the-student-that-will-replace-the-chalk
2044-number-of-wonderful-substrings
2059-unique-length-3-palindromic-subsequences
2145-grid-game
2240-intervals-between-identical-elements
2358-number-of-ways-to-split-array
2394-count-subarrays-with-score-less-than-k
2488-divide-intervals-into-minimum-number-of-groups
2691-count-vowel-strings-in-ranges
2915-count-of-interesting-subarrays
3031-construct-product-matrix
3475-minimum-operations-to-make-binary-array-elements-equal-to-one-i
3639-zero-array-transformation-i
3643-zero-array-transformation-ii

Backtracking

0040-combination-sum-ii
0051-n-queens
0052-n-queens-ii
0078-subsets
0079-word-search
0113-path-sum-ii
0212-word-search-ii
0301-remove-invalid-parentheses
0494-target-sum
0691-stickers-to-spell-word
0800-letter-case-permutation
1160-letter-tile-possibilities
1516-the-k-th-lexicographical-string-of-all-happy-strings-of-length-n
1715-split-a-string-into-the-max-number-of-unique-substrings
1993-sum-of-all-subset-xor-totals
2107-find-unique-binary-string
2170-count-number-of-maximum-bitwise-or-subsets
2802-find-the-punishment-number-of-an-integer

Doubly-Linked List

0146-lru-cache
0460-lfu-cache

Binary Search Tree

0235-lowest-common-ancestor-of-a-binary-search-tree
1475-maximum-sum-bst-in-binary-tree
2567-closest-nodes-queries-in-a-binary-search-tree

Data Stream

0295-find-median-from-data-stream
1477-product-of-the-last-k-numbers

Queue

0225-implement-stack-using-queues
0859-design-circular-deque
0860-design-circular-queue
2868-continuous-subarrays
3209-minimum-number-of-coins-for-fruits
3475-minimum-operations-to-make-binary-array-elements-equal-to-one-i

Monotonic Queue

2868-continuous-subarrays
3209-minimum-number-of-coins-for-fruits

Combinatorics

0062-unique-paths
1761-count-sorted-vowel-strings
1993-sum-of-all-subset-xor-totals

Geometry

2575-minimum-cuts-to-divide-a-circle
3278-find-the-number-of-ways-to-place-people-i

Number Theory

2595-smallest-value-after-replacing-with-sum-of-prime-factors
2610-closest-prime-numbers-in-range
2903-insert-greatest-common-divisors-in-linked-list
3702-maximum-subarray-with-equal-products

Quickselect

0324-wiggle-sort-ii
0347-top-k-frequent-elements

Brainteaser

2503-longest-subarray-with-maximum-bitwise-and
2533-bitwise-xor-of-all-pairings

Rolling Hash

0214-shortest-palindrome
1508-longest-happy-prefix
3309-count-prefix-and-suffix-pairs-i

Hash Function

0214-shortest-palindrome
0572-subtree-of-another-tree
1508-longest-happy-prefix
3309-count-prefix-and-suffix-pairs-i

Bitmask

0691-stickers-to-spell-word

Enumeration

1656-count-good-triplets
1993-sum-of-all-subset-xor-totals
2170-count-number-of-maximum-bitwise-or-subsets
2215-finding-3-digit-even-numbers
2998-count-symmetric-integers
3278-find-the-number-of-ways-to-place-people-i
3683-find-the-lexicographically-largest-string-from-the-box-i
3702-maximum-subarray-with-equal-products