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

LeetCode Topics

Array

0001-two-sum
0011-container-with-most-water
0014-longest-common-prefix
0015-3sum
0016-3sum-closest
0018-4sum
0026-remove-duplicates-from-sorted-array
0027-remove-element
0033-search-in-rotated-sorted-array
0034-find-first-and-last-position-of-element-in-sorted-array
0035-search-insert-position
0036-valid-sudoku
0042-trapping-rain-water
0045-jump-game-ii
0048-rotate-image
0049-group-anagrams
0053-maximum-subarray
0054-spiral-matrix
0059-spiral-matrix-ii
0066-plus-one
0073-set-matrix-zeroes
0074-search-a-2d-matrix
0075-sort-colors
0078-subsets
0080-remove-duplicates-from-sorted-array-ii
0081-search-in-rotated-sorted-array-ii
0088-merge-sorted-array
0118-pascals-triangle
0120-triangle
0121-best-time-to-buy-and-sell-stock
0122-best-time-to-buy-and-sell-stock-ii
0128-longest-consecutive-sequence
0134-gas-station
0135-candy
0136-single-number
0152-maximum-product-subarray
0153-find-minimum-in-rotated-sorted-array
0162-find-peak-element
0164-maximum-gap
0167-two-sum-ii-input-array-is-sorted
0169-majority-element
0179-largest-number
0189-rotate-array
0204-count-primes
0209-minimum-size-subarray-sum
0215-kth-largest-element-in-an-array
0217-contains-duplicate
0219-contains-duplicate-ii
0229-majority-element-ii
0238-product-of-array-except-self
0240-search-a-2d-matrix-ii
0260-single-number-iii
0268-missing-number
0283-move-zeroes
0287-find-the-duplicate-number
0347-top-k-frequent-elements
0349-intersection-of-two-arrays
0378-kth-smallest-element-in-a-sorted-matrix
0407-trapping-rain-water-ii
0410-split-array-largest-sum
0417-pacific-atlantic-water-flow
0442-find-all-duplicates-in-an-array
0455-assign-cookies
0463-island-perimeter
0485-max-consecutive-ones
0498-diagonal-traverse
0540-single-element-in-a-sorted-array
0560-subarray-sum-equals-k
0566-reshape-the-matrix
0594-longest-harmonious-subsequence
0611-valid-triangle-number
0632-smallest-range-covering-elements-from-k-lists
0643-maximum-average-subarray-i
0679-24-game
0682-baseball-game
0724-find-pivot-index
0729-my-calendar-i
0745-find-smallest-letter-greater-than-target
0792-binary-search
0794-swim-in-rising-water
0797-rabbits-in-forest
0816-design-hashset
0830-largest-triangle-area
0854-making-a-large-island
0882-peak-index-in-a-mountain-array
0890-lemonade-change
0898-transpose-matrix
0905-length-of-longest-fibonacci-subsequence
0917-boats-to-save-people
0925-construct-binary-tree-from-preorder-and-postorder-traversal
0934-bitwise-ors-of-subarrays
0940-fruit-into-baskets
0945-snakes-and-ladders
0948-sort-an-array
0952-word-subsets
1002-maximum-width-ramp
1006-vowel-spellchecker
1018-largest-perimeter-triangle
1019-squares-of-a-sorted-array
1046-max-consecutive-ones-iii
1049-minimum-domino-rotations-for-equal-row
1111-minimum-score-triangulation-of-polygon
1227-number-of-equivalent-domino-pairs
1231-replace-elements-with-greatest-element-on-right-side
1256-rank-transform-of-an-array
1293-three-consecutive-odds
1335-maximum-candies-allocated-to-k-children
1350-remove-sub-folders-from-the-filesystem
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
1424-maximum-candies-you-can-get-from-boxes
1426-find-n-unique-integers-sum-up-to-zero
1435-xor-queries-of-a-subarray
1468-check-if-n-and-its-double-exist
1476-count-negative-numbers-in-a-sorted-matrix
1477-product-of-the-last-k-numbers
1478-maximum-number-of-events-that-can-be-attended
1485-minimum-cost-to-make-at-least-one-valid-path-in-a-grid
1497-design-a-stack-with-increment-operation
1524-string-matching-in-an-array
1586-longest-subarray-of-1s-after-deleting-one-element
1603-running-sum-of-1d-array
1612-avoid-flood-in-the-city
1620-check-if-array-pairs-are-divisible-by-k
1621-number-of-subsequences-that-satisfy-the-given-sum-condition
1628-count-submatrices-with-all-ones
1631-number-of-sub-arrays-with-odd-sum
1646-kth-missing-positive-number
1656-count-good-triplets
1677-matrix-diagonal-sum
1694-make-sum-divisible-by-p
1730-special-array-with-x-elements-greater-than-or-equal-x
1755-defuse-the-bomb
1786-count-the-number-of-consistent-strings
1791-richest-customer-wealth
1813-maximum-erasure-value
1819-construct-the-lexicographically-largest-valid-sequence
1833-find-the-highest-altitude
1834-minimum-number-of-people-to-teach
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
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
1972-rotating-the-box
1988-minimize-maximum-pair-sum-in-array
1993-sum-of-all-subset-xor-totals
1995-finding-pairs-with-a-certain-sum
2023-design-movie-rental-system
2048-build-array-from-permutation
2054-the-number-of-the-smallest-unoccupied-chair
2058-concatenation-of-array
2079-delete-duplicate-folders-in-system
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
2150-kth-smallest-product-of-two-sorted-arrays
2160-minimum-operations-to-make-a-uni-value-grid
2170-count-number-of-maximum-bitwise-or-subsets
2180-maximum-number-of-tasks-you-can-assign
2204-find-subsequence-of-length-k-with-the-largest-sum
2210-find-target-indices-after-sorting-array
2215-finding-3-digit-even-numbers
2220-find-all-possible-recipes-from-given-supplies
2227-sum-of-subarray-ranges
2229-maximum-fruits-harvested-after-at-most-k-steps
2232-adding-spaces-to-a-string
2237-longest-palindrome-by-concatenating-two-letter-words
2249-count-the-hidden-sequences
2265-partition-array-according-to-given-pivot
2277-count-equal-and-divisible-pairs-in-an-array
2280-count-good-triplets-in-an-array
2292-counting-words-with-a-given-prefix
2307-replace-non-coprime-numbers-in-array
2308-divide-array-into-equal-pairs
2320-find-all-k-distant-indices-in-an-array
2324-find-triangular-sum-of-an-array
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
2392-successful-pairs-of-spells-and-potions
2394-count-subarrays-with-score-less-than-k
2400-minimum-score-after-removals-on-a-tree
2411-spiral-matrix-iv
2429-design-a-food-rating-system
2432-number-of-zero-filled-subarrays
2448-count-number-of-bad-pairs
2465-shifting-letters-ii
2473-max-sum-of-a-pair-with-equal-sum-of-digits
2478-longest-nice-subarray
2479-meeting-rooms-iii
2488-divide-intervals-into-minimum-number-of-groups
2497-maximum-matching-of-players-with-trainers
2498-smallest-subarrays-with-maximum-bitwise-or
2503-longest-subarray-with-maximum-bitwise-and
2529-range-product-queries-of-powers
2533-bitwise-xor-of-all-pairings
2551-apply-operations-to-an-array
2552-maximum-sum-of-distinct-subarrays-with-length-k
2564-most-profitable-path-in-a-tree
2581-divide-players-into-teams-of-equal-skill
2588-maximum-number-of-points-from-grid-queries
2614-maximum-count-of-positive-integer-and-negative-integer
2616-maximal-score-after-applying-k-operations
2626-count-the-number-of-good-subarrays
2665-minimum-time-to-repair-cars
2681-put-marbles-in-bags
2685-first-completely-painted-row-or-column
2689-rearranging-fruits
2690-house-robber-iv
2691-count-vowel-strings-in-ranges
2699-count-the-number-of-fair-pairs
2707-merge-two-2d-arrays-by-summing-values
2764-maximum-number-of-fish-in-a-grid
2766-find-the-prefix-common-array-of-two-arrays
2792-neighboring-bitwise-xor
2856-count-complete-subarrays-in-an-array
2868-continuous-subarrays
2888-minimum-index-of-a-valid-split
3001-apply-operations-to-maximize-score
3142-longest-unequal-adjacent-groups-subsequence-ii
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
3213-count-subarrays-where-max-element-appears-at-least-k-times
3219-make-lexicographically-smallest-array-by-swapping-elements
3227-find-missing-and-repeated-values
3241-divide-array-into-arrays-with-max-difference
3242-count-elements-with-maximum-frequency
3251-maximum-area-of-longest-diagonal-rectangle
3277-find-the-number-of-ways-to-place-people-ii
3278-find-the-number-of-ways-to-place-people-i
3291-find-if-array-can-be-sorted
3307-find-the-maximum-sum-of-node-values
3309-count-prefix-and-suffix-pairs-i
3321-type-of-triangle
3332-minimum-operations-to-exceed-threshold-value-ii
3348-minimum-cost-walk-in-weighted-graph
3372-longest-strictly-increasing-or-strictly-decreasing-subarray
3383-taking-maximum-energy-from-the-mystic-dungeon
3429-special-array-i
3430-count-days-without-meetings
3434-find-the-number-of-distinct-colors-among-the-balls
3437-maximum-total-damage-with-spell-casting
3459-find-the-minimum-area-to-cover-all-ones-ii
3461-find-the-minimum-area-to-cover-all-ones-i
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
3501-delete-nodes-from-linked-list-present-in-array
3522-find-the-power-of-k-size-subarrays-i
3612-adjacent-increasing-subarrays-detection-i
3619-adjacent-increasing-subarrays-detection-ii
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
3643-zero-array-transformation-ii
3648-find-the-maximum-number-of-fruits-collected
3656-minimum-number-of-operations-to-make-elements-in-array-distinct
3657-check-if-grid-can-be-cut-into-sections
3685-count-subarrays-of-length-three-with-a-condition
3733-length-of-longest-v-shaped-diagonal-segment
3741-reschedule-meetings-for-maximum-free-time-ii
3743-reschedule-meetings-for-maximum-free-time-i
3744-minimum-operations-to-make-array-elements-zero
3747-maximum-difference-between-adjacent-elements-in-a-circular-array
3748-sort-matrix-by-diagonals
3788-maximum-unique-subarray-sum-after-deletion
3789-maximize-subarrays-after-removing-one-conflicting-pair
3790-fruits-into-baskets-ii
3791-fruits-into-baskets-iii
3794-find-the-minimum-amount-of-time-to-brew-potions
3797-design-spreadsheet
3827-implement-router
3851-find-sum-of-array-product-of-magical-sequences

Linked List

0002-add-two-numbers
0019-remove-nth-node-from-end-of-list
0021-merge-two-sorted-lists
0061-rotate-list
0083-remove-duplicates-from-sorted-list
0092-reverse-linked-list-ii
0141-linked-list-cycle
0142-linked-list-cycle-ii
0147-insertion-sort-list
0160-intersection-of-two-linked-lists
0203-remove-linked-list-elements
0206-reverse-linked-list
0234-palindrome-linked-list
0237-delete-node-in-a-linked-list
0328-odd-even-linked-list
0816-design-hashset
0908-middle-of-the-linked-list
1411-convert-binary-number-in-a-linked-list-to-integer
2216-delete-the-middle-node-of-a-linked-list
2411-spiral-matrix-iv
2903-insert-greatest-common-divisors-in-linked-list
3501-delete-nodes-from-linked-list-present-in-array

Matrix

0036-valid-sudoku
0048-rotate-image
0054-spiral-matrix
0059-spiral-matrix-ii
0073-set-matrix-zeroes
0074-search-a-2d-matrix
0240-search-a-2d-matrix-ii
0378-kth-smallest-element-in-a-sorted-matrix
0407-trapping-rain-water-ii
0417-pacific-atlantic-water-flow
0463-island-perimeter
0498-diagonal-traverse
0566-reshape-the-matrix
0794-swim-in-rising-water
0854-making-a-large-island
0898-transpose-matrix
0945-snakes-and-ladders
1396-count-servers-that-communicate
1402-count-square-submatrices-with-all-ones
1476-count-negative-numbers-in-a-sorted-matrix
1485-minimum-cost-to-make-at-least-one-valid-path-in-a-grid
1628-count-submatrices-with-all-ones
1677-matrix-diagonal-sum
1791-richest-customer-wealth
1876-map-of-highest-peak
1972-rotating-the-box
2089-maximum-matrix-sum
2132-convert-1d-array-into-2d-array
2145-grid-game
2160-minimum-operations-to-make-a-uni-value-grid
2411-spiral-matrix-iv
2588-maximum-number-of-points-from-grid-queries
2685-first-completely-painted-row-or-column
2764-maximum-number-of-fish-in-a-grid
3227-find-missing-and-repeated-values
3459-find-the-minimum-area-to-cover-all-ones-ii
3461-find-the-minimum-area-to-cover-all-ones-i
3627-find-minimum-time-to-reach-last-room-i
3628-find-minimum-time-to-reach-last-room-ii
3648-find-the-maximum-number-of-fruits-collected
3733-length-of-longest-v-shaped-diagonal-segment
3748-sort-matrix-by-diagonals
3797-design-spreadsheet

Simulation

0043-multiply-strings
0054-spiral-matrix
0059-spiral-matrix-ii
0067-add-binary
0412-fizz-buzz
0415-add-strings
0498-diagonal-traverse
0566-reshape-the-matrix
0657-robot-return-to-origin
0682-baseball-game
0874-backspace-string-compare
0898-transpose-matrix
1642-water-bottles
2021-remove-all-occurrences-of-a-substring
2048-build-array-from-permutation
2058-concatenation-of-array
2132-convert-1d-array-into-2d-array
2232-adding-spaces-to-a-string
2260-divide-a-string-into-groups-of-size-k
2265-partition-array-according-to-given-pivot
2324-find-triangular-sum-of-an-array
2408-number-of-people-aware-of-a-secret
2411-spiral-matrix-iv
2479-meeting-rooms-iii
2551-apply-operations-to-an-array
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
3790-fruits-into-baskets-ii
3794-find-the-minimum-amount-of-time-to-brew-potions

Math

0002-add-two-numbers
0007-reverse-integer
0009-palindrome-number
0013-roman-to-integer
0043-multiply-strings
0048-rotate-image
0050-powx-n
0066-plus-one
0067-add-binary
0069-sqrtx
0070-climbing-stairs
0096-unique-binary-search-trees
0166-fraction-to-recurring-decimal
0168-excel-sheet-column-title
0189-rotate-array
0202-happy-number
0204-count-primes
0231-power-of-two
0241-different-ways-to-add-parentheses
0268-missing-number
0326-power-of-three
0342-power-of-four
0367-valid-perfect-square
0412-fizz-buzz
0415-add-strings
0670-maximum-swap
0679-24-game
0797-rabbits-in-forest
0826-soup-servings
0830-largest-triangle-area
0867-new-21-game
0900-reordered-power-of-2
1013-fibonacci-number
1018-largest-perimeter-triangle
1146-greatest-common-divisor-of-strings
1236-n-th-tribonacci-number
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
1444-number-of-steps-to-reduce-a-number-to-zero
1448-maximum-69-number
1477-product-of-the-last-k-numbers
1500-count-largest-group
1529-max-difference-you-can-get-from-changing-an-integer
1631-number-of-sub-arrays-with-odd-sum
1642-water-bottles
1889-check-if-number-is-a-sum-of-powers-of-three
1993-sum-of-all-subset-xor-totals
2032-largest-odd-number-in-string
2160-minimum-operations-to-make-a-uni-value-grid
2202-sum-of-k-mirror-numbers
2307-replace-non-coprime-numbers-in-array
2324-find-triangular-sum-of-an-array
2415-count-the-number-of-ideal-arrays
2432-number-of-zero-filled-subarrays
2448-count-number-of-bad-pairs
2610-closest-prime-numbers-in-range
2649-count-total-number-of-colored-cells
2704-maximum-difference-by-remapping-a-digit
2802-find-the-punishment-number-of-an-integer
2903-insert-greatest-common-divisors-in-linked-list
3001-apply-operations-to-maximize-score
3172-divisible-and-non-divisible-sums-difference
3201-distribute-candies-among-children-ii
3227-find-missing-and-repeated-values
3243-count-the-number-of-powerful-integers
3277-find-the-number-of-ways-to-place-people-ii
3278-find-the-number-of-ways-to-place-people-i
3279-alice-and-bob-playing-flower-game
3321-type-of-triangle
3336-water-bottles-ii
3462-vowels-game-in-a-string
3548-find-the-count-of-good-integers
3601-find-the-k-th-character-in-string-game-ii
3629-total-characters-in-string-after-transformations-i
3630-total-characters-in-string-after-transformations-ii
3682-count-the-number-of-arrays-with-k-matching-adjacent-elements
3744-minimum-operations-to-make-array-elements-zero
3754-maximum-manhattan-distance-after-k-changes
3830-find-closest-person
3851-find-sum-of-array-product-of-magical-sequences

Number Theory

0204-count-primes
2307-replace-non-coprime-numbers-in-array
2415-count-the-number-of-ideal-arrays
2610-closest-prime-numbers-in-range
2903-insert-greatest-common-divisors-in-linked-list
3001-apply-operations-to-maximize-score

Hash Table

0001-two-sum
0003-longest-substring-without-repeating-characters
0013-roman-to-integer
0036-valid-sudoku
0049-group-anagrams
0073-set-matrix-zeroes
0128-longest-consecutive-sequence
0141-linked-list-cycle
0142-linked-list-cycle-ii
0160-intersection-of-two-linked-lists
0166-fraction-to-recurring-decimal
0169-majority-element
0202-happy-number
0205-isomorphic-strings
0217-contains-duplicate
0219-contains-duplicate-ii
0229-majority-element-ii
0242-valid-anagram
0268-missing-number
0347-top-k-frequent-elements
0349-intersection-of-two-arrays
0387-first-unique-character-in-a-string
0389-find-the-difference
0442-find-all-duplicates-in-an-array
0560-subarray-sum-equals-k
0567-permutation-in-string
0594-longest-harmonious-subsequence
0632-smallest-range-covering-elements-from-k-lists
0768-partition-labels
0797-rabbits-in-forest
0816-design-hashset
0900-reordered-power-of-2
0905-length-of-longest-fibonacci-subsequence
0920-uncommon-words-from-two-sentences
0925-construct-binary-tree-from-preorder-and-postorder-traversal
0940-fruit-into-baskets
0952-word-subsets
1006-vowel-spellchecker
1160-letter-tile-possibilities
1218-lowest-common-ancestor-of-deepest-leaves
1227-number-of-equivalent-domino-pairs
1256-rank-transform-of-an-array
1264-maximum-number-of-words-you-can-type
1353-find-resultant-array-after-removing-anagrams
1364-tuple-with-same-product
1387-find-elements-in-a-contaminated-binary-tree
1460-number-of-substrings-containing-all-three-characters
1468-check-if-n-and-its-double-exist
1500-count-largest-group
1502-construct-k-palindrome-strings
1612-avoid-flood-in-the-city
1620-check-if-array-pairs-are-divisible-by-k
1694-make-sum-divisible-by-p
1786-count-the-number-of-consistent-strings
1813-maximum-erasure-value
1834-minimum-number-of-people-to-teach
1915-check-if-one-string-swap-can-make-strings-equal
1986-largest-color-value-in-a-directed-graph
1995-finding-pairs-with-a-certain-sum
2023-design-movie-rental-system
2054-the-number-of-the-smallest-unoccupied-chair
2059-unique-length-3-palindromic-subsequences
2079-delete-duplicate-folders-in-system
2107-find-unique-binary-string
2204-find-subsequence-of-length-k-with-the-largest-sum
2215-finding-3-digit-even-numbers
2220-find-all-possible-recipes-from-given-supplies
2237-longest-palindrome-by-concatenating-two-letter-words
2308-divide-array-into-equal-pairs
2356-largest-combination-with-bitwise-and-greater-than-zero
2429-design-a-food-rating-system
2434-design-a-number-container-system
2448-count-number-of-bad-pairs
2473-max-sum-of-a-pair-with-equal-sum-of-digits
2479-meeting-rooms-iii
2520-using-a-robot-to-print-the-lexicographically-smallest-string
2552-maximum-sum-of-distinct-subarrays-with-length-k
2581-divide-players-into-teams-of-equal-skill
2626-count-the-number-of-good-subarrays
2685-first-completely-painted-row-or-column
2689-rearranging-fruits
2707-merge-two-2d-arrays-by-summing-values
2766-find-the-prefix-common-array-of-two-arrays
2856-count-complete-subarrays-in-an-array
2888-minimum-index-of-a-valid-split
3227-find-missing-and-repeated-values
3242-count-elements-with-maximum-frequency
3360-minimum-deletions-to-make-string-k-special
3408-count-the-number-of-special-characters-i
3434-find-the-number-of-distinct-colors-among-the-balls
3437-maximum-total-damage-with-spell-casting
3445-lexicographically-minimum-string-after-removing-stars
3455-minimum-length-of-string-after-operations
3501-delete-nodes-from-linked-list-present-in-array
3548-find-the-count-of-good-integers
3569-count-of-substrings-containing-every-vowel-and-k-consonants-ii
3621-minimum-operations-to-make-array-values-equal-to-k
3629-total-characters-in-string-after-transformations-i
3630-total-characters-in-string-after-transformations-ii
3656-minimum-number-of-operations-to-make-elements-in-array-distinct
3678-design-task-manager
3753-maximum-difference-between-even-and-odd-frequency-i
3754-maximum-manhattan-distance-after-k-changes
3788-maximum-unique-subarray-sum-after-deletion
3797-design-spreadsheet
3827-implement-router
3872-find-most-frequent-vowel-and-consonant

Database

0176-second-highest-salary
0595-big-countries
1509-replace-employee-id-with-the-unique-identifier
1811-fix-names-in-a-table
1908-recyclable-and-low-fat-products

Bit Manipulation

0067-add-binary
0078-subsets
0136-single-number
0191-number-of-1-bits
0231-power-of-two
0260-single-number-iii
0268-missing-number
0287-find-the-duplicate-number
0338-counting-bits
0342-power-of-four
0389-find-the-difference
0401-binary-watch
0934-bitwise-ors-of-subarrays
1435-xor-queries-of-a-subarray
1444-number-of-steps-to-reduce-a-number-to-zero
1786-count-the-number-of-consistent-strings
1993-sum-of-all-subset-xor-totals
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
2400-minimum-score-after-removals-on-a-tree
2478-longest-nice-subarray
2498-smallest-subarrays-with-maximum-bitwise-or
2503-longest-subarray-with-maximum-bitwise-and
2509-minimize-xor
2529-range-product-queries-of-powers
2533-bitwise-xor-of-all-pairings
2766-find-the-prefix-common-array-of-two-arrays
2792-neighboring-bitwise-xor
2837-minimum-operations-to-make-the-integer-zero
3291-find-if-array-can-be-sorted
3307-find-the-maximum-sum-of-node-values
3348-minimum-cost-walk-in-weighted-graph
3475-minimum-operations-to-make-binary-array-elements-equal-to-one-i
3601-find-the-k-th-character-in-string-game-ii
3744-minimum-operations-to-make-array-elements-zero
3851-find-sum-of-array-product-of-magical-sequences

Two Pointers

0005-longest-palindromic-substring
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
0027-remove-element
0028-find-the-index-of-the-first-occurrence-in-a-string
0042-trapping-rain-water
0061-rotate-list
0075-sort-colors
0080-remove-duplicates-from-sorted-array-ii
0088-merge-sorted-array
0125-valid-palindrome
0141-linked-list-cycle
0142-linked-list-cycle-ii
0151-reverse-words-in-a-string
0160-intersection-of-two-linked-lists
0165-compare-version-numbers
0167-two-sum-ii-input-array-is-sorted
0189-rotate-array
0202-happy-number
0234-palindrome-linked-list
0283-move-zeroes
0287-find-the-duplicate-number
0344-reverse-string
0345-reverse-vowels-of-a-string
0349-intersection-of-two-arrays
0392-is-subsequence
0455-assign-cookies
0567-permutation-in-string
0611-valid-triangle-number
0680-valid-palindrome-ii
0768-partition-labels
0868-push-dominoes
0874-backspace-string-compare
0908-middle-of-the-linked-list
0917-boats-to-save-people
1019-squares-of-a-sorted-array
1468-check-if-n-and-its-double-exist
1566-check-if-a-word-occurs-as-a-prefix-of-any-word-in-a-sentence
1621-number-of-subsequences-that-satisfy-the-given-sum-condition
1894-merge-strings-alternately
1923-sentence-similarity-iii
1972-rotating-the-box
1988-minimize-maximum-pair-sum-in-array
2095-minimum-number-of-swaps-to-make-the-string-balanced
2216-delete-the-middle-node-of-a-linked-list
2232-adding-spaces-to-a-string
2265-partition-array-according-to-given-pivot
2320-find-all-k-distant-indices-in-an-array
2392-successful-pairs-of-spells-and-potions
2488-divide-intervals-into-minimum-number-of-groups
2497-maximum-matching-of-players-with-trainers
2551-apply-operations-to-an-array
2572-append-characters-to-string-to-make-subsequence
2581-divide-players-into-teams-of-equal-skill
2588-maximum-number-of-points-from-grid-queries
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
3437-maximum-total-damage-with-spell-casting
3683-find-the-lexicographically-largest-string-from-the-box-i

Divide and Conquer

0053-maximum-subarray
0169-majority-element
0191-number-of-1-bits
0215-kth-largest-element-in-an-array
0240-search-a-2d-matrix-ii
0347-top-k-frequent-elements
0925-construct-binary-tree-from-preorder-and-postorder-traversal
0948-sort-an-array
2280-count-good-triplets-in-an-array

Sorting

0015-3sum
0016-3sum-closest
0018-4sum
0049-group-anagrams
0075-sort-colors
0088-merge-sorted-array
0147-insertion-sort-list
0164-maximum-gap
0169-majority-element
0179-largest-number
0215-kth-largest-element-in-an-array
0217-contains-duplicate
0229-majority-element-ii
0242-valid-anagram
0268-missing-number
0347-top-k-frequent-elements
0349-intersection-of-two-arrays
0378-kth-smallest-element-in-a-sorted-matrix
0389-find-the-difference
0455-assign-cookies
0594-longest-harmonious-subsequence
0611-valid-triangle-number
0632-smallest-range-covering-elements-from-k-lists
0900-reordered-power-of-2
0917-boats-to-save-people
0948-sort-an-array
1018-largest-perimeter-triangle
1019-squares-of-a-sorted-array
1256-rank-transform-of-an-array
1353-find-resultant-array-after-removing-anagrams
1468-check-if-n-and-its-double-exist
1478-maximum-number-of-events-that-can-be-attended
1621-number-of-subsequences-that-satisfy-the-given-sum-condition
1730-special-array-with-x-elements-greater-than-or-equal-x
1851-maximum-number-of-events-that-can-be-attended-ii
1988-minimize-maximum-pair-sum-in-array
2160-minimum-operations-to-make-a-uni-value-grid
2180-maximum-number-of-tasks-you-can-assign
2204-find-subsequence-of-length-k-with-the-largest-sum
2210-find-target-indices-after-sorting-array
2215-finding-3-digit-even-numbers
2387-partition-array-such-that-maximum-difference-is-k
2392-successful-pairs-of-spells-and-potions
2473-max-sum-of-a-pair-with-equal-sum-of-digits
2479-meeting-rooms-iii
2488-divide-intervals-into-minimum-number-of-groups
2497-maximum-matching-of-players-with-trainers
2581-divide-players-into-teams-of-equal-skill
2588-maximum-number-of-points-from-grid-queries
2681-put-marbles-in-bags
2689-rearranging-fruits
2699-count-the-number-of-fair-pairs
2887-sort-vowels-in-a-string
2888-minimum-index-of-a-valid-split
3001-apply-operations-to-maximize-score
3219-make-lexicographically-smallest-array-by-swapping-elements
3241-divide-array-into-arrays-with-max-difference
3277-find-the-number-of-ways-to-place-people-ii
3278-find-the-number-of-ways-to-place-people-i
3291-find-if-array-can-be-sorted
3307-find-the-maximum-sum-of-node-values
3321-type-of-triangle
3360-minimum-deletions-to-make-string-k-special
3430-count-days-without-meetings
3437-maximum-total-damage-with-spell-casting
3657-check-if-grid-can-be-cut-into-sections
3748-sort-matrix-by-diagonals

Counting

0169-majority-element
0229-majority-element-ii
0347-top-k-frequent-elements
0387-first-unique-character-in-a-string
0594-longest-harmonious-subsequence
0900-reordered-power-of-2
0920-uncommon-words-from-two-sentences
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
1986-largest-color-value-in-a-directed-graph
2140-longest-subsequence-repeated-k-times
2237-longest-palindrome-by-concatenating-two-letter-words
2308-divide-array-into-equal-pairs
2356-largest-combination-with-bitwise-and-greater-than-zero
2448-count-number-of-bad-pairs
2614-maximum-count-of-positive-integer-and-negative-integer
3242-count-elements-with-maximum-frequency
3360-minimum-deletions-to-make-string-k-special
3437-maximum-total-damage-with-spell-casting
3455-minimum-length-of-string-after-operations
3629-total-characters-in-string-after-transformations-i
3630-total-characters-in-string-after-transformations-ii
3753-maximum-difference-between-even-and-odd-frequency-i
3754-maximum-manhattan-distance-after-k-changes
3872-find-most-frequent-vowel-and-consonant

Dynamic Programming

0005-longest-palindromic-substring
0032-longest-valid-parentheses
0042-trapping-rain-water
0045-jump-game-ii
0053-maximum-subarray
0070-climbing-stairs
0096-unique-binary-search-trees
0118-pascals-triangle
0120-triangle
0121-best-time-to-buy-and-sell-stock
0122-best-time-to-buy-and-sell-stock-ii
0131-palindrome-partitioning
0152-maximum-product-subarray
0241-different-ways-to-add-parentheses
0338-counting-bits
0392-is-subsequence
0410-split-array-largest-sum
0806-domino-and-tromino-tiling
0826-soup-servings
0867-new-21-game
0868-push-dominoes
0905-length-of-longest-fibonacci-subsequence
0934-bitwise-ors-of-subarrays
1013-fibonacci-number
1111-minimum-score-triangulation-of-polygon
1170-shortest-common-supersequence
1236-n-th-tribonacci-number
1402-count-square-submatrices-with-all-ones
1586-longest-subarray-of-1s-after-deleting-one-element
1628-count-submatrices-with-all-ones
1631-number-of-sub-arrays-with-odd-sum
1849-maximum-absolute-sum-of-any-subarray
1851-maximum-number-of-events-that-can-be-attended-ii
1986-largest-color-value-in-a-directed-graph
2028-the-earliest-and-latest-rounds-where-players-compete
2061-painting-a-grid-with-three-different-colors
2090-number-of-ways-to-arrive-at-destination
2395-longest-binary-subsequence-less-than-or-equal-to-k
2408-number-of-people-aware-of-a-secret
2415-count-the-number-of-ideal-arrays
2882-ways-to-express-an-integer-as-sum-of-powers
3142-longest-unequal-adjacent-groups-subsequence-ii
3243-count-the-number-of-powerful-integers
3307-find-the-maximum-sum-of-node-values
3437-maximum-total-damage-with-spell-casting
3490-find-the-maximum-length-of-valid-subsequence-i
3618-find-the-original-typed-string-ii
3629-total-characters-in-string-after-transformations-i
3630-total-characters-in-string-after-transformations-ii
3648-find-the-maximum-number-of-fruits-collected
3733-length-of-longest-v-shaped-diagonal-segment
3851-find-sum-of-array-product-of-magical-sequences

String

0003-longest-substring-without-repeating-characters
0005-longest-palindromic-substring
0013-roman-to-integer
0014-longest-common-prefix
0020-valid-parentheses
0028-find-the-index-of-the-first-occurrence-in-a-string
0032-longest-valid-parentheses
0038-count-and-say
0043-multiply-strings
0049-group-anagrams
0058-length-of-last-word
0067-add-binary
0125-valid-palindrome
0131-palindrome-partitioning
0151-reverse-words-in-a-string
0165-compare-version-numbers
0166-fraction-to-recurring-decimal
0168-excel-sheet-column-title
0179-largest-number
0205-isomorphic-strings
0241-different-ways-to-add-parentheses
0242-valid-anagram
0257-binary-tree-paths
0344-reverse-string
0345-reverse-vowels-of-a-string
0387-first-unique-character-in-a-string
0389-find-the-difference
0392-is-subsequence
0412-fizz-buzz
0415-add-strings
0520-detect-capital
0567-permutation-in-string
0657-robot-return-to-origin
0680-valid-palindrome-ii
0742-to-lower-case
0768-partition-labels
0812-rotate-string
0868-push-dominoes
0874-backspace-string-compare
0920-uncommon-words-from-two-sentences
0952-word-subsets
0957-minimum-add-to-make-parentheses-valid
1006-vowel-spellchecker
1058-lexicographically-smallest-equivalent-string
1078-remove-outermost-parentheses
1093-recover-a-tree-from-preorder-traversal
1146-greatest-common-divisor-of-strings
1160-letter-tile-possibilities
1170-shortest-common-supersequence
1264-maximum-number-of-words-you-can-type
1302-delete-characters-to-make-fancy-string
1350-remove-sub-folders-from-the-filesystem
1353-find-resultant-array-after-removing-anagrams
1460-number-of-substrings-containing-all-three-characters
1502-construct-k-palindrome-strings
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
1786-count-the-number-of-consistent-strings
1818-maximum-score-from-removing-substrings
1894-merge-strings-alternately
1895-minimum-number-of-operations-to-move-all-balls-to-each-box
1910-check-if-binary-string-has-at-most-one-segment-of-ones
1915-check-if-one-string-swap-can-make-strings-equal
1923-sentence-similarity-iii
2021-remove-all-occurrences-of-a-substring
2032-largest-odd-number-in-string
2059-unique-length-3-palindromic-subsequences
2079-delete-duplicate-folders-in-system
2095-minimum-number-of-swaps-to-make-the-string-balanced
2107-find-unique-binary-string
2140-longest-subsequence-repeated-k-times
2220-find-all-possible-recipes-from-given-supplies
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
2292-counting-words-with-a-given-prefix
2346-largest-3-same-digit-number-in-string
2395-longest-binary-subsequence-less-than-or-equal-to-k
2429-design-a-food-rating-system
2456-construct-smallest-number-from-di-string
2463-minimum-recolors-to-get-k-consecutive-black-blocks
2465-shifting-letters-ii
2520-using-a-robot-to-print-the-lexicographically-smallest-string
2572-append-characters-to-string-to-make-subsequence
2580-circular-sentence
2691-count-vowel-strings-in-ranges
2800-minimum-string-length-after-removing-substrings
2887-sort-vowels-in-a-string
3018-make-string-a-subsequence-using-cyclic-increments
3142-longest-unequal-adjacent-groups-subsequence-ii
3174-minimum-number-of-changes-to-make-binary-string-beautiful
3194-find-words-containing-character
3195-separate-black-and-white-balls
3243-count-the-number-of-powerful-integers
3309-count-prefix-and-suffix-pairs-i
3360-minimum-deletions-to-make-string-k-special
3396-valid-word
3408-count-the-number-of-special-characters-i
3445-lexicographically-minimum-string-after-removing-stars
3447-clear-digits
3451-string-compression-iii
3455-minimum-length-of-string-after-operations
3462-vowels-game-in-a-string
3569-count-of-substrings-containing-every-vowel-and-k-consonants-ii
3617-find-the-original-typed-string-i
3618-find-the-original-typed-string-ii
3629-total-characters-in-string-after-transformations-i
3630-total-characters-in-string-after-transformations-ii
3683-find-the-lexicographically-largest-string-from-the-box-i
3753-maximum-difference-between-even-and-odd-frequency-i
3754-maximum-manhattan-distance-after-k-changes
3761-maximum-difference-between-even-and-odd-frequency-ii
3797-design-spreadsheet
3872-find-most-frequent-vowel-and-consonant

Prefix Sum

0209-minimum-size-subarray-sum
0238-product-of-array-except-self
0410-split-array-largest-sum
0560-subarray-sum-equals-k
0724-find-pivot-index
1046-max-consecutive-ones-iii
1435-xor-queries-of-a-subarray
1477-product-of-the-last-k-numbers
1537-maximum-score-after-splitting-a-string
1603-running-sum-of-1d-array
1631-number-of-sub-arrays-with-odd-sum
1694-make-sum-divisible-by-p
1833-find-the-highest-altitude
1895-minimum-number-of-operations-to-move-all-balls-to-each-box
2059-unique-length-3-palindromic-subsequences
2145-grid-game
2229-maximum-fruits-harvested-after-at-most-k-steps
2249-count-the-hidden-sequences
2358-number-of-ways-to-split-array
2394-count-subarrays-with-score-less-than-k
2465-shifting-letters-ii
2488-divide-intervals-into-minimum-number-of-groups
2529-range-product-queries-of-powers
2691-count-vowel-strings-in-ranges
3383-taking-maximum-energy-from-the-mystic-dungeon
3475-minimum-operations-to-make-binary-array-elements-equal-to-one-i
3618-find-the-original-typed-string-ii
3643-zero-array-transformation-ii
3761-maximum-difference-between-even-and-odd-frequency-ii
3789-maximize-subarrays-after-removing-one-conflicting-pair
3794-find-the-minimum-amount-of-time-to-brew-potions

Binary Search

0033-search-in-rotated-sorted-array
0034-find-first-and-last-position-of-element-in-sorted-array
0035-search-insert-position
0069-sqrtx
0074-search-a-2d-matrix
0081-search-in-rotated-sorted-array-ii
0153-find-minimum-in-rotated-sorted-array
0162-find-peak-element
0167-two-sum-ii-input-array-is-sorted
0209-minimum-size-subarray-sum
0240-search-a-2d-matrix-ii
0268-missing-number
0278-first-bad-version
0287-find-the-duplicate-number
0349-intersection-of-two-arrays
0367-valid-perfect-square
0374-guess-number-higher-or-lower
0378-kth-smallest-element-in-a-sorted-matrix
0410-split-array-largest-sum
0540-single-element-in-a-sorted-array
0611-valid-triangle-number
0729-my-calendar-i
0745-find-smallest-letter-greater-than-target
0792-binary-search
0794-swim-in-rising-water
0882-peak-index-in-a-mountain-array
1046-max-consecutive-ones-iii
1335-maximum-candies-allocated-to-k-children
1468-check-if-n-and-its-double-exist
1476-count-negative-numbers-in-a-sorted-matrix
1612-avoid-flood-in-the-city
1621-number-of-subsequences-that-satisfy-the-given-sum-condition
1646-kth-missing-positive-number
1730-special-array-with-x-elements-greater-than-or-equal-x
1851-maximum-number-of-events-that-can-be-attended-ii
2150-kth-smallest-product-of-two-sorted-arrays
2180-maximum-number-of-tasks-you-can-assign
2210-find-target-indices-after-sorting-array
2229-maximum-fruits-harvested-after-at-most-k-steps
2280-count-good-triplets-in-an-array
2392-successful-pairs-of-spells-and-potions
2394-count-subarrays-with-score-less-than-k
2498-smallest-subarrays-with-maximum-bitwise-or
2614-maximum-count-of-positive-integer-and-negative-integer
2665-minimum-time-to-repair-cars
2690-house-robber-iv
2699-count-the-number-of-fair-pairs
3437-maximum-total-damage-with-spell-casting
3619-adjacent-increasing-subarrays-detection-ii
3643-zero-array-transformation-ii
3790-fruits-into-baskets-ii
3791-fruits-into-baskets-iii
3827-implement-router

Trie

0014-longest-common-prefix
0386-lexicographical-numbers
0440-k-th-smallest-in-lexicographical-order
1350-remove-sub-folders-from-the-filesystem
2079-delete-duplicate-folders-in-system
3309-count-prefix-and-suffix-pairs-i

Greedy

0011-container-with-most-water
0045-jump-game-ii
0122-best-time-to-buy-and-sell-stock-ii
0134-gas-station
0135-candy
0179-largest-number
0410-split-array-largest-sum
0455-assign-cookies
0611-valid-triangle-number
0632-smallest-range-covering-elements-from-k-lists
0670-maximum-swap
0680-valid-palindrome-ii
0768-partition-labels
0797-rabbits-in-forest
0890-lemonade-change
0917-boats-to-save-people
0957-minimum-add-to-make-parentheses-valid
1018-largest-perimeter-triangle
1049-minimum-domino-rotations-for-equal-row
1448-maximum-69-number
1478-maximum-number-of-events-that-can-be-attended
1502-construct-k-palindrome-strings
1529-max-difference-you-can-get-from-changing-an-integer
1612-avoid-flood-in-the-city
1818-maximum-score-from-removing-substrings
1834-minimum-number-of-people-to-teach
1917-maximum-average-pass-ratio
1988-minimize-maximum-pair-sum-in-array
2032-largest-odd-number-in-string
2089-maximum-matrix-sum
2095-minimum-number-of-swaps-to-make-the-string-balanced
2140-longest-subsequence-repeated-k-times
2180-maximum-number-of-tasks-you-can-assign
2221-check-if-a-parentheses-string-can-be-valid
2237-longest-palindrome-by-concatenating-two-letter-words
2387-partition-array-such-that-maximum-difference-is-k
2395-longest-binary-subsequence-less-than-or-equal-to-k
2456-construct-smallest-number-from-di-string
2488-divide-intervals-into-minimum-number-of-groups
2497-maximum-matching-of-players-with-trainers
2509-minimize-xor
2520-using-a-robot-to-print-the-lexicographically-smallest-string
2572-append-characters-to-string-to-make-subsequence
2616-maximal-score-after-applying-k-operations
2681-put-marbles-in-bags
2689-rearranging-fruits
2704-maximum-difference-by-remapping-a-digit
3001-apply-operations-to-maximize-score
3171-minimum-equal-sum-of-two-arrays-after-replacing-zeros
3195-separate-black-and-white-balls
3241-divide-array-into-arrays-with-max-difference
3307-find-the-maximum-sum-of-node-values
3360-minimum-deletions-to-make-string-k-special
3445-lexicographically-minimum-string-after-removing-stars
3741-reschedule-meetings-for-maximum-free-time-ii
3743-reschedule-meetings-for-maximum-free-time-i
3788-maximum-unique-subarray-sum-after-deletion

Recursion

0002-add-two-numbers
0021-merge-two-sorted-lists
0050-powx-n
0203-remove-linked-list-elements
0206-reverse-linked-list
0231-power-of-two
0234-palindrome-linked-list
0241-different-ways-to-add-parentheses
0326-power-of-three
0342-power-of-four
1013-fibonacci-number
3601-find-the-k-th-character-in-string-game-ii

Memoization

0070-climbing-stairs
0241-different-ways-to-add-parentheses
1013-fibonacci-number
1236-n-th-tribonacci-number
1986-largest-color-value-in-a-directed-graph
2028-the-earliest-and-latest-rounds-where-players-compete
2395-longest-binary-subsequence-less-than-or-equal-to-k
3733-length-of-longest-v-shaped-diagonal-segment

Design

0155-min-stack
0232-implement-queue-using-stacks
0729-my-calendar-i
0789-kth-largest-element-in-a-stream
0816-design-hashset
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
2023-design-movie-rental-system
2429-design-a-food-rating-system
2434-design-a-number-container-system
3678-design-task-manager
3797-design-spreadsheet
3827-implement-router

Segment Tree

0729-my-calendar-i
2280-count-good-triplets-in-an-array
3789-maximize-subarrays-after-removing-one-conflicting-pair
3790-fruits-into-baskets-ii
3791-fruits-into-baskets-iii

Ordered Set

0729-my-calendar-i
2023-design-movie-rental-system
2280-count-good-triplets-in-an-array
2429-design-a-food-rating-system
2434-design-a-number-container-system
2868-continuous-subarrays
3678-design-task-manager
3790-fruits-into-baskets-ii
3791-fruits-into-baskets-iii
3827-implement-router

Stack

0020-valid-parentheses
0032-longest-valid-parentheses
0042-trapping-rain-water
0094-binary-tree-inorder-traversal
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0155-min-stack
0232-implement-queue-using-stacks
0234-palindrome-linked-list
0682-baseball-game
0874-backspace-string-compare
0957-minimum-add-to-make-parentheses-valid
1002-maximum-width-ramp
1078-remove-outermost-parentheses
1497-design-a-stack-with-increment-operation
1628-count-submatrices-with-all-ones
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
2227-sum-of-subarray-ranges
2307-replace-non-coprime-numbers-in-array
2456-construct-smallest-number-from-di-string
2520-using-a-robot-to-print-the-lexicographically-smallest-string
2800-minimum-string-length-after-removing-substrings
3001-apply-operations-to-maximize-score
3445-lexicographically-minimum-string-after-removing-stars
3447-clear-digits

Tree

0094-binary-tree-inorder-traversal
0096-unique-binary-search-trees
0098-validate-binary-search-tree
0100-same-tree
0101-symmetric-tree
0102-binary-tree-level-order-traversal
0104-maximum-depth-of-binary-tree
0110-balanced-binary-tree
0112-path-sum
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0199-binary-tree-right-side-view
0226-invert-binary-tree
0257-binary-tree-paths
0404-sum-of-left-leaves
0543-diameter-of-binary-tree
0572-subtree-of-another-tree
0637-average-of-levels-in-binary-tree
0789-kth-largest-element-in-a-stream
0904-leaf-similar-trees
0925-construct-binary-tree-from-preorder-and-postorder-traversal
1093-recover-a-tree-from-preorder-traversal
1114-binary-search-tree-to-greater-sum-tree
1218-lowest-common-ancestor-of-deepest-leaves
1387-find-elements-in-a-contaminated-binary-tree
2400-minimum-score-after-removals-on-a-tree
2564-most-profitable-path-in-a-tree
3307-find-the-maximum-sum-of-node-values
3645-maximize-the-number-of-target-nodes-after-connecting-trees-ii

Depth-First Search

0094-binary-tree-inorder-traversal
0098-validate-binary-search-tree
0100-same-tree
0101-symmetric-tree
0104-maximum-depth-of-binary-tree
0110-balanced-binary-tree
0112-path-sum
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0199-binary-tree-right-side-view
0226-invert-binary-tree
0257-binary-tree-paths
0386-lexicographical-numbers
0404-sum-of-left-leaves
0417-pacific-atlantic-water-flow
0463-island-perimeter
0543-diameter-of-binary-tree
0572-subtree-of-another-tree
0637-average-of-levels-in-binary-tree
0684-redundant-connection
0794-swim-in-rising-water
0820-find-eventual-safe-states
0854-making-a-large-island
0904-leaf-similar-trees
1093-recover-a-tree-from-preorder-traversal
1114-binary-search-tree-to-greater-sum-tree
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
1558-course-schedule-iv
2246-maximum-employees-to-be-invited-to-a-meeting
2400-minimum-score-after-removals-on-a-tree
2438-find-closest-node-to-given-two-nodes
2564-most-profitable-path-in-a-tree
2764-maximum-number-of-fish-in-a-grid
2793-count-the-number-of-complete-components
3645-maximize-the-number-of-target-nodes-after-connecting-trees-ii

Binary Tree

0094-binary-tree-inorder-traversal
0096-unique-binary-search-trees
0098-validate-binary-search-tree
0100-same-tree
0101-symmetric-tree
0102-binary-tree-level-order-traversal
0104-maximum-depth-of-binary-tree
0110-balanced-binary-tree
0112-path-sum
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0199-binary-tree-right-side-view
0226-invert-binary-tree
0257-binary-tree-paths
0404-sum-of-left-leaves
0543-diameter-of-binary-tree
0572-subtree-of-another-tree
0637-average-of-levels-in-binary-tree
0789-kth-largest-element-in-a-stream
0904-leaf-similar-trees
0925-construct-binary-tree-from-preorder-and-postorder-traversal
1093-recover-a-tree-from-preorder-traversal
1114-binary-search-tree-to-greater-sum-tree
1218-lowest-common-ancestor-of-deepest-leaves
1387-find-elements-in-a-contaminated-binary-tree

Sliding Window

0003-longest-substring-without-repeating-characters
0209-minimum-size-subarray-sum
0219-contains-duplicate-ii
0567-permutation-in-string
0594-longest-harmonious-subsequence
0632-smallest-range-covering-elements-from-k-lists
0643-maximum-average-subarray-i
0867-new-21-game
0940-fruit-into-baskets
1046-max-consecutive-ones-iii
1460-number-of-substrings-containing-all-three-characters
1586-longest-subarray-of-1s-after-deleting-one-element
1755-defuse-the-bomb
1813-maximum-erasure-value
2229-maximum-fruits-harvested-after-at-most-k-steps
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
2626-count-the-number-of-good-subarrays
2856-count-complete-subarrays-in-an-array
2868-continuous-subarrays
3213-count-subarrays-where-max-element-appears-at-least-k-times
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
3569-count-of-substrings-containing-every-vowel-and-k-consonants-ii
3743-reschedule-meetings-for-maximum-free-time-i
3761-maximum-difference-between-even-and-odd-frequency-ii

Breadth-First Search

0100-same-tree
0101-symmetric-tree
0102-binary-tree-level-order-traversal
0104-maximum-depth-of-binary-tree
0112-path-sum
0199-binary-tree-right-side-view
0226-invert-binary-tree
0404-sum-of-left-leaves
0407-trapping-rain-water-ii
0417-pacific-atlantic-water-flow
0463-island-perimeter
0637-average-of-levels-in-binary-tree
0684-redundant-connection
0794-swim-in-rising-water
0820-find-eventual-safe-states
0854-making-a-large-island
0945-snakes-and-ladders
1218-lowest-common-ancestor-of-deepest-leaves
1387-find-elements-in-a-contaminated-binary-tree
1396-count-servers-that-communicate
1424-maximum-candies-you-can-get-from-boxes
1485-minimum-cost-to-make-at-least-one-valid-path-in-a-grid
1558-course-schedule-iv
1876-map-of-highest-peak
2564-most-profitable-path-in-a-tree
2583-divide-nodes-into-the-maximum-number-of-groups
2588-maximum-number-of-points-from-grid-queries
2764-maximum-number-of-fish-in-a-grid
2793-count-the-number-of-complete-components
3645-maximize-the-number-of-target-nodes-after-connecting-trees-ii

Monotonic Stack

0042-trapping-rain-water
1002-maximum-width-ramp
1628-count-submatrices-with-all-ones
2227-sum-of-subarray-ranges
3001-apply-operations-to-maximize-score

Heap (Priority Queue)

0215-kth-largest-element-in-an-array
0347-top-k-frequent-elements
0378-kth-smallest-element-in-a-sorted-matrix
0407-trapping-rain-water-ii
0632-smallest-range-covering-elements-from-k-lists
0789-kth-largest-element-in-a-stream
0794-swim-in-rising-water
0948-sort-an-array
1478-maximum-number-of-events-that-can-be-attended
1485-minimum-cost-to-make-at-least-one-valid-path-in-a-grid
1612-avoid-flood-in-the-city
1917-maximum-average-pass-ratio
2023-design-movie-rental-system
2054-the-number-of-the-smallest-unoccupied-chair
2204-find-subsequence-of-length-k-with-the-largest-sum
2429-design-a-food-rating-system
2434-design-a-number-container-system
2473-max-sum-of-a-pair-with-equal-sum-of-digits
2479-meeting-rooms-iii
2488-divide-intervals-into-minimum-number-of-groups
2588-maximum-number-of-points-from-grid-queries
2616-maximal-score-after-applying-k-operations
2681-put-marbles-in-bags
2868-continuous-subarrays
3332-minimum-operations-to-exceed-threshold-value-ii
3445-lexicographically-minimum-string-after-removing-stars
3627-find-minimum-time-to-reach-last-room-i
3628-find-minimum-time-to-reach-last-room-ii
3678-design-task-manager

String Matching

0028-find-the-index-of-the-first-occurrence-in-a-string
0572-subtree-of-another-tree
0812-rotate-string
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

Backtracking

0078-subsets
0131-palindrome-partitioning
0257-binary-tree-paths
0401-binary-watch
0679-24-game
1160-letter-tile-possibilities
1516-the-k-th-lexicographical-string-of-all-happy-strings-of-length-n
1819-construct-the-lexicographically-largest-valid-sequence
1993-sum-of-all-subset-xor-totals
2107-find-unique-binary-string
2140-longest-subsequence-repeated-k-times
2170-count-number-of-maximum-bitwise-or-subsets
2456-construct-smallest-number-from-di-string
2802-find-the-punishment-number-of-an-integer

Queue

0232-implement-queue-using-stacks
0387-first-unique-character-in-a-string
2180-maximum-number-of-tasks-you-can-assign
2408-number-of-people-aware-of-a-secret
2868-continuous-subarrays
3475-minimum-operations-to-make-binary-array-elements-equal-to-one-i
3827-implement-router

Monotonic Queue

2180-maximum-number-of-tasks-you-can-assign
2868-continuous-subarrays

Quickselect

0215-kth-largest-element-in-an-array
0347-top-k-frequent-elements

Union Find

0128-longest-consecutive-sequence
0684-redundant-connection
0794-swim-in-rising-water
0854-making-a-large-island
1058-lexicographically-smallest-equivalent-string
1396-count-servers-that-communicate
2583-divide-nodes-into-the-maximum-number-of-groups
2588-maximum-number-of-points-from-grid-queries
2764-maximum-number-of-fish-in-a-grid
2793-count-the-number-of-complete-components
3219-make-lexicographically-smallest-array-by-swapping-elements
3348-minimum-cost-walk-in-weighted-graph

Rolling Hash

3309-count-prefix-and-suffix-pairs-i

Hash Function

0572-subtree-of-another-tree
0816-design-hashset
2079-delete-duplicate-folders-in-system
3309-count-prefix-and-suffix-pairs-i

Brainteaser

2503-longest-subarray-with-maximum-bitwise-and
2533-bitwise-xor-of-all-pairings
2837-minimum-operations-to-make-the-integer-zero
3462-vowels-game-in-a-string

Graph

0684-redundant-connection
0820-find-eventual-safe-states
1424-maximum-candies-you-can-get-from-boxes
1485-minimum-cost-to-make-at-least-one-valid-path-in-a-grid
1558-course-schedule-iv
1986-largest-color-value-in-a-directed-graph
2090-number-of-ways-to-arrive-at-destination
2220-find-all-possible-recipes-from-given-supplies
2246-maximum-employees-to-be-invited-to-a-meeting
2438-find-closest-node-to-given-two-nodes
2564-most-profitable-path-in-a-tree
2583-divide-nodes-into-the-maximum-number-of-groups
2793-count-the-number-of-complete-components
3348-minimum-cost-walk-in-weighted-graph
3627-find-minimum-time-to-reach-last-room-i
3628-find-minimum-time-to-reach-last-room-ii

Shortest Path

1485-minimum-cost-to-make-at-least-one-valid-path-in-a-grid
2090-number-of-ways-to-arrive-at-destination
3627-find-minimum-time-to-reach-last-room-i
3628-find-minimum-time-to-reach-last-room-ii

Topological Sort

0820-find-eventual-safe-states
1558-course-schedule-iv
1986-largest-color-value-in-a-directed-graph
2090-number-of-ways-to-arrive-at-destination
2220-find-all-possible-recipes-from-given-supplies
2246-maximum-employees-to-be-invited-to-a-meeting

Data Stream

0789-kth-largest-element-in-a-stream
1477-product-of-the-last-k-numbers

Merge Sort

0948-sort-an-array
2280-count-good-triplets-in-an-array

Bucket Sort

0164-maximum-gap
0347-top-k-frequent-elements
0948-sort-an-array

Radix Sort

0164-maximum-gap
0948-sort-an-array

Counting Sort

0948-sort-an-array

Interactive

0278-first-bad-version
0374-guess-number-higher-or-lower

Binary Search Tree

0096-unique-binary-search-trees
0098-validate-binary-search-tree
0789-kth-largest-element-in-a-stream
1114-binary-search-tree-to-greater-sum-tree

Combinatorics

1993-sum-of-all-subset-xor-totals
2324-find-triangular-sum-of-an-array
2415-count-the-number-of-ideal-arrays
3201-distribute-candies-among-children-ii
3548-find-the-count-of-good-integers
3682-count-the-number-of-arrays-with-k-matching-adjacent-elements
3851-find-sum-of-array-product-of-magical-sequences

Enumeration

0204-count-primes
0900-reordered-power-of-2
1656-count-good-triplets
1993-sum-of-all-subset-xor-totals
2140-longest-subsequence-repeated-k-times
2170-count-number-of-maximum-bitwise-or-subsets
2202-sum-of-k-mirror-numbers
2215-finding-3-digit-even-numbers
2837-minimum-operations-to-make-the-integer-zero
3201-distribute-candies-among-children-ii
3277-find-the-number-of-ways-to-place-people-ii
3278-find-the-number-of-ways-to-place-people-i
3459-find-the-minimum-area-to-cover-all-ones-ii
3548-find-the-count-of-good-integers
3683-find-the-lexicographically-largest-string-from-the-box-i
3741-reschedule-meetings-for-maximum-free-time-ii
3761-maximum-difference-between-even-and-odd-frequency-ii
3789-maximize-subarrays-after-removing-one-conflicting-pair

Binary Indexed Tree

2280-count-good-triplets-in-an-array

Probability and Statistics

0826-soup-servings
0867-new-21-game

Geometry

0830-largest-triangle-area
3277-find-the-number-of-ways-to-place-people-ii
3278-find-the-number-of-ways-to-place-people-i

Game Theory

3462-vowels-game-in-a-string

Bitmask

3851-find-sum-of-array-product-of-magical-sequences