LeetCode-Solutions

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

LeetCode Topics

Array

0001-two-sum
0011-container-with-most-water
0016-3sum-closest
0027-remove-element
0034-find-first-and-last-position-of-element-in-sorted-array
0039-combination-sum
0046-permutations
0048-rotate-image
0049-group-anagrams
0053-maximum-subarray
0054-spiral-matrix
0066-plus-one
0074-search-a-2d-matrix
0075-sort-colors
0078-subsets
0108-convert-sorted-array-to-binary-search-tree
0119-pascals-triangle-ii
0134-gas-station
0153-find-minimum-in-rotated-sorted-array
0167-two-sum-ii-input-array-is-sorted
0169-majority-element
0179-largest-number
0189-rotate-array
0217-contains-duplicate
0229-majority-element-ii
0238-product-of-array-except-self
0268-missing-number
0275-h-index-ii
0283-move-zeroes
0303-range-sum-query-immutable
0304-range-sum-query-2d-immutable
0347-top-k-frequent-elements
0368-largest-divisible-subset
0380-insert-delete-getrandom-o1
0442-find-all-duplicates-in-an-array
0448-find-all-numbers-disappeared-in-an-array
0452-minimum-number-of-arrows-to-burst-balloons
0456-132-pattern
0475-heaters
0498-diagonal-traverse
0500-keyboard-row
0560-subarray-sum-equals-k
0599-minimum-index-sum-of-two-lists
0628-maximum-product-of-three-numbers
0643-maximum-average-subarray-i
0645-set-mismatch
0661-image-smoother
0690-employee-importance
0695-max-area-of-island
0722-remove-comments
0724-find-pivot-index
0733-flood-fill
0739-daily-temperatures
0792-binary-search
0797-rabbits-in-forest
0829-subdomain-visit-count
0859-design-circular-deque
0890-lemonade-change
0898-transpose-matrix
0907-koko-eating-bananas
0917-boats-to-save-people
0925-construct-binary-tree-from-preorder-and-postorder-traversal
0943-sum-of-subarray-minimums
0945-snakes-and-ladders
0948-sort-an-array
0966-binary-subarrays-with-sum
0987-reveal-cards-in-increasing-order
1009-pancake-sorting
1016-subarray-sums-divisible-by-k
1027-sum-of-even-numbers-after-queries
1028-interval-list-intersections
1036-rotting-oranges
1046-max-consecutive-ones-iii
1049-minimum-domino-rotations-for-equal-row
1112-find-words-that-can-be-formed-by-characters
1227-number-of-equivalent-domino-pairs
1293-three-consecutive-odds
1354-find-players-with-zero-or-one-losses
1364-tuple-with-same-product
1418-fair-distribution-of-cookies
1421-find-numbers-with-even-number-of-digits
1449-print-words-vertically
1477-product-of-the-last-k-numbers
1482-how-many-numbers-are-smaller-than-the-current-number
1538-maximum-points-you-can-obtain-from-cards
1549-longest-continuous-subarray-with-absolute-diff-less-than-or-equal-to-limit
1582-design-browser-history
1603-running-sum-of-1d-array
1651-shuffle-string
1656-count-good-triplets
1675-magnetic-force-between-two-balls
1683-maximum-number-of-coins-you-can-get
1695-maximum-sum-obtained-of-any-permutation
1720-crawler-log-folder
1786-count-the-number-of-consistent-strings
1791-richest-customer-wealth
1819-construct-the-lexicographically-largest-valid-sequence
1927-maximum-ascending-subarray-sum
1951-find-the-winner-of-the-circular-game
1961-maximum-ice-cream-bars
1993-sum-of-all-subset-xor-totals
2015-determine-whether-matrix-can-be-obtained-by-rotation
2048-build-array-from-permutation
2058-concatenation-of-array
2148-minimum-number-of-moves-to-seat-everyone
2160-minimum-operations-to-make-a-uni-value-grid
2180-maximum-number-of-tasks-you-can-assign
2210-find-target-indices-after-sorting-array
2220-find-all-possible-recipes-from-given-supplies
2249-count-the-hidden-sequences
2308-divide-array-into-equal-pairs
2394-count-subarrays-with-score-less-than-k
2421-maximum-number-of-pairs-in-array
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
2502-sort-the-people
2519-find-the-original-array-of-prefix-xor
2527-count-subarrays-with-fixed-bounds
2551-apply-operations-to-an-array
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
2626-count-the-number-of-good-subarrays
2631-sort-the-students-by-their-kth-score
2639-separate-the-digits-in-an-array
2690-house-robber-iv
2699-count-the-number-of-fair-pairs
2856-count-complete-subarrays-in-an-array
2888-minimum-index-of-a-valid-split
2915-count-of-interesting-subarrays
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
3213-count-subarrays-where-max-element-appears-at-least-k-times
3227-find-missing-and-repeated-values
3332-minimum-operations-to-exceed-threshold-value-ii
3348-minimum-cost-walk-in-weighted-graph
3372-longest-strictly-increasing-or-strictly-decreasing-subarray
3430-count-days-without-meetings
3475-minimum-operations-to-make-binary-array-elements-equal-to-one-i
3483-alternating-groups-ii
3581-the-two-sneaky-numbers-of-digitville
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
3651-transformed-array
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

Hash Table

0001-two-sum
0003-longest-substring-without-repeating-characters
0012-integer-to-roman
0049-group-anagrams
0076-minimum-window-substring
0141-linked-list-cycle
0142-linked-list-cycle-ii
0146-lru-cache
0169-majority-element
0217-contains-duplicate
0229-majority-element-ii
0242-valid-anagram
0268-missing-number
0347-top-k-frequent-elements
0380-insert-delete-getrandom-o1
0387-first-unique-character-in-a-string
0438-find-all-anagrams-in-a-string
0442-find-all-duplicates-in-an-array
0448-find-all-numbers-disappeared-in-an-array
0451-sort-characters-by-frequency
0500-keyboard-row
0560-subarray-sum-equals-k
0567-permutation-in-string
0599-minimum-index-sum-of-two-lists
0645-set-mismatch
0690-employee-importance
0768-partition-labels
0797-rabbits-in-forest
0829-subdomain-visit-count
0925-construct-binary-tree-from-preorder-and-postorder-traversal
0966-binary-subarrays-with-sum
1016-subarray-sums-divisible-by-k
1112-find-words-that-can-be-formed-by-characters
1160-letter-tile-possibilities
1218-lowest-common-ancestor-of-deepest-leaves
1227-number-of-equivalent-domino-pairs
1354-find-players-with-zero-or-one-losses
1364-tuple-with-same-product
1387-find-elements-in-a-contaminated-binary-tree
1469-minimum-number-of-steps-to-make-two-strings-anagram
1482-how-many-numbers-are-smaller-than-the-current-number
1500-count-largest-group
1786-count-the-number-of-consistent-strings
1915-check-if-one-string-swap-can-make-strings-equal
2053-check-if-all-characters-have-equal-number-of-occurrences
2220-find-all-possible-recipes-from-given-supplies
2308-divide-array-into-equal-pairs
2421-maximum-number-of-pairs-in-array
2434-design-a-number-container-system
2448-count-number-of-bad-pairs
2473-max-sum-of-a-pair-with-equal-sum-of-digits
2502-sort-the-people
2581-divide-players-into-teams-of-equal-skill
2626-count-the-number-of-good-subarrays
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
3548-find-the-count-of-good-integers
3569-count-of-substrings-containing-every-vowel-and-k-consonants-ii
3581-the-two-sneaky-numbers-of-digitville
3621-minimum-operations-to-make-array-values-equal-to-k
3656-minimum-number-of-operations-to-make-elements-in-array-distinct

Sorting

0016-3sum-closest
0049-group-anagrams
0075-sort-colors
0148-sort-list
0169-majority-element
0179-largest-number
0217-contains-duplicate
0229-majority-element-ii
0242-valid-anagram
0268-missing-number
0347-top-k-frequent-elements
0368-largest-divisible-subset
0451-sort-characters-by-frequency
0452-minimum-number-of-arrows-to-burst-balloons
0475-heaters
0628-maximum-product-of-three-numbers
0645-set-mismatch
0917-boats-to-save-people
0948-sort-an-array
0987-reveal-cards-in-increasing-order
1009-pancake-sorting
1354-find-players-with-zero-or-one-losses
1482-how-many-numbers-are-smaller-than-the-current-number
1675-magnetic-force-between-two-balls
1683-maximum-number-of-coins-you-can-get
1695-maximum-sum-obtained-of-any-permutation
1961-maximum-ice-cream-bars
2148-minimum-number-of-moves-to-seat-everyone
2160-minimum-operations-to-make-a-uni-value-grid
2180-maximum-number-of-tasks-you-can-assign
2210-find-target-indices-after-sorting-array
2473-max-sum-of-a-pair-with-equal-sum-of-digits
2502-sort-the-people
2581-divide-players-into-teams-of-equal-skill
2588-maximum-number-of-points-from-grid-queries
2631-sort-the-students-by-their-kth-score
2699-count-the-number-of-fair-pairs
2888-minimum-index-of-a-valid-split
3430-count-days-without-meetings
3657-check-if-grid-can-be-cut-into-sections

Counting

0169-majority-element
0229-majority-element-ii
0347-top-k-frequent-elements
0387-first-unique-character-in-a-string
0451-sort-characters-by-frequency
0829-subdomain-visit-count
1112-find-words-that-can-be-formed-by-characters
1160-letter-tile-possibilities
1227-number-of-equivalent-domino-pairs
1341-split-a-string-in-balanced-strings
1354-find-players-with-zero-or-one-losses
1364-tuple-with-same-product
1469-minimum-number-of-steps-to-make-two-strings-anagram
1482-how-many-numbers-are-smaller-than-the-current-number
1786-count-the-number-of-consistent-strings
1915-check-if-one-string-swap-can-make-strings-equal
2053-check-if-all-characters-have-equal-number-of-occurrences
2308-divide-array-into-equal-pairs
2421-maximum-number-of-pairs-in-array
2448-count-number-of-bad-pairs
2614-maximum-count-of-positive-integer-and-negative-integer

Simulation

0054-spiral-matrix
0067-add-binary
0415-add-strings
0498-diagonal-traverse
0874-backspace-string-compare
0898-transpose-matrix
0987-reveal-cards-in-increasing-order
1027-sum-of-even-numbers-after-queries
1449-print-words-vertically
1667-find-kth-bit-in-nth-binary-string
1951-find-the-winner-of-the-circular-game
2021-remove-all-occurrences-of-a-substring
2048-build-array-from-permutation
2058-concatenation-of-array
2470-removing-stars-from-a-string
2551-apply-operations-to-an-array
2639-separate-the-digits-in-an-array
3332-minimum-operations-to-exceed-threshold-value-ii
3447-clear-digits
3651-transformed-array

String

0003-longest-substring-without-repeating-characters
0012-integer-to-roman
0020-valid-parentheses
0038-count-and-say
0049-group-anagrams
0067-add-binary
0071-simplify-path
0076-minimum-window-substring
0093-restore-ip-addresses
0168-excel-sheet-column-title
0179-largest-number
0242-valid-anagram
0344-reverse-string
0387-first-unique-character-in-a-string
0394-decode-string
0415-add-strings
0438-find-all-anagrams-in-a-string
0451-sort-characters-by-frequency
0500-keyboard-row
0567-permutation-in-string
0599-minimum-index-sum-of-two-lists
0680-valid-palindrome-ii
0722-remove-comments
0768-partition-labels
0829-subdomain-visit-count
0858-masking-personal-information
0868-push-dominoes
0874-backspace-string-compare
0886-score-of-parentheses
1093-recover-a-tree-from-preorder-traversal
1112-find-words-that-can-be-formed-by-characters
1160-letter-tile-possibilities
1341-split-a-string-in-balanced-strings
1449-print-words-vertically
1469-minimum-number-of-steps-to-make-two-strings-anagram
1516-the-k-th-lexicographical-string-of-all-happy-strings-of-length-n
1651-shuffle-string
1667-find-kth-bit-in-nth-binary-string
1720-crawler-log-folder
1786-count-the-number-of-consistent-strings
1915-check-if-one-string-swap-can-make-strings-equal
1976-splitting-a-string-into-descending-consecutive-values
2021-remove-all-occurrences-of-a-substring
2053-check-if-all-characters-have-equal-number-of-occurrences
2220-find-all-possible-recipes-from-given-supplies
2456-construct-smallest-number-from-di-string
2463-minimum-recolors-to-get-k-consecutive-black-blocks
2465-shifting-letters-ii
2470-removing-stars-from-a-string
2502-sort-the-people
3195-separate-black-and-white-balls
3243-count-the-number-of-powerful-integers
3447-clear-digits
3569-count-of-substrings-containing-every-vowel-and-k-consonants-ii
3637-count-number-of-balanced-permutations

Queue

0225-implement-stack-using-queues
0232-implement-queue-using-stacks
0387-first-unique-character-in-a-string
0859-design-circular-deque
0987-reveal-cards-in-increasing-order
1549-longest-continuous-subarray-with-absolute-diff-less-than-or-equal-to-limit
1951-find-the-winner-of-the-circular-game
2180-maximum-number-of-tasks-you-can-assign
2527-count-subarrays-with-fixed-bounds
3475-minimum-operations-to-make-binary-array-elements-equal-to-one-i

Divide and Conquer

0053-maximum-subarray
0108-convert-sorted-array-to-binary-search-tree
0148-sort-list
0169-majority-element
0347-top-k-frequent-elements
0925-construct-binary-tree-from-preorder-and-postorder-traversal
0948-sort-an-array

Heap (Priority Queue)

0347-top-k-frequent-elements
0451-sort-characters-by-frequency
0789-kth-largest-element-in-a-stream
0948-sort-an-array
1549-longest-continuous-subarray-with-absolute-diff-less-than-or-equal-to-limit
2434-design-a-number-container-system
2473-max-sum-of-a-pair-with-equal-sum-of-digits
2588-maximum-number-of-points-from-grid-queries
3332-minimum-operations-to-exceed-threshold-value-ii
3627-find-minimum-time-to-reach-last-room-i
3628-find-minimum-time-to-reach-last-room-ii

Bucket Sort

0347-top-k-frequent-elements
0451-sort-characters-by-frequency
0948-sort-an-array

Quickselect

0347-top-k-frequent-elements

Math

0007-reverse-integer
0012-integer-to-roman
0048-rotate-image
0050-powx-n
0066-plus-one
0067-add-binary
0069-sqrtx
0168-excel-sheet-column-title
0172-factorial-trailing-zeroes
0189-rotate-array
0231-power-of-two
0263-ugly-number
0268-missing-number
0326-power-of-three
0342-power-of-four
0368-largest-divisible-subset
0380-insert-delete-getrandom-o1
0415-add-strings
0628-maximum-product-of-three-numbers
0633-sum-of-square-numbers
0797-rabbits-in-forest
1303-minimum-moves-to-reach-target-score
1421-find-numbers-with-even-number-of-digits
1477-product-of-the-last-k-numbers
1500-count-largest-group
1683-maximum-number-of-coins-you-can-get
1951-find-the-winner-of-the-circular-game
1993-sum-of-all-subset-xor-totals
2050-count-good-numbers
2160-minimum-operations-to-make-a-uni-value-grid
2415-count-the-number-of-ideal-arrays
2448-count-number-of-bad-pairs
2649-count-total-number-of-colored-cells
2802-find-the-punishment-number-of-an-integer
2998-count-symmetric-integers
3227-find-missing-and-repeated-values
3243-count-the-number-of-powerful-integers
3548-find-the-count-of-good-integers
3581-the-two-sneaky-numbers-of-digitville
3637-count-number-of-balanced-permutations

Bit Manipulation

0067-add-binary
0078-subsets
0231-power-of-two
0268-missing-number
0338-counting-bits
0342-power-of-four
0645-set-mismatch
1418-fair-distribution-of-cookies
1786-count-the-number-of-consistent-strings
1993-sum-of-all-subset-xor-totals
2308-divide-array-into-equal-pairs
2478-longest-nice-subarray
2519-find-the-original-array-of-prefix-xor
3348-minimum-cost-walk-in-weighted-graph
3475-minimum-operations-to-make-binary-array-elements-equal-to-one-i

Two Pointers

0011-container-with-most-water
0016-3sum-closest
0019-remove-nth-node-from-end-of-list
0027-remove-element
0075-sort-colors
0141-linked-list-cycle
0142-linked-list-cycle-ii
0148-sort-list
0167-two-sum-ii-input-array-is-sorted
0189-rotate-array
0234-palindrome-linked-list
0283-move-zeroes
0344-reverse-string
0475-heaters
0567-permutation-in-string
0633-sum-of-square-numbers
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
1009-pancake-sorting
1028-interval-list-intersections
2551-apply-operations-to-an-array
2581-divide-players-into-teams-of-equal-skill
2588-maximum-number-of-points-from-grid-queries
2699-count-the-number-of-fair-pairs
3195-separate-black-and-white-balls

Recursion

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
0326-power-of-three
0342-power-of-four
0394-decode-string
1667-find-kth-bit-in-nth-binary-string
1951-find-the-winner-of-the-circular-game
2050-count-good-numbers

Matrix

0048-rotate-image
0054-spiral-matrix
0074-search-a-2d-matrix
0304-range-sum-query-2d-immutable
0498-diagonal-traverse
0661-image-smoother
0695-max-area-of-island
0733-flood-fill
0898-transpose-matrix
0945-snakes-and-ladders
1036-rotting-oranges
1791-richest-customer-wealth
2015-determine-whether-matrix-can-be-obtained-by-rotation
2160-minimum-operations-to-make-a-uni-value-grid
2588-maximum-number-of-points-from-grid-queries
2631-sort-the-students-by-their-kth-score
3227-find-missing-and-repeated-values
3627-find-minimum-time-to-reach-last-room-i
3628-find-minimum-time-to-reach-last-room-ii

Design

0146-lru-cache
0225-implement-stack-using-queues
0232-implement-queue-using-stacks
0303-range-sum-query-immutable
0304-range-sum-query-2d-immutable
0380-insert-delete-getrandom-o1
0789-kth-largest-element-in-a-stream
0838-design-linked-list
0859-design-circular-deque
1387-find-elements-in-a-contaminated-binary-tree
1477-product-of-the-last-k-numbers
1582-design-browser-history
2434-design-a-number-container-system

Ordered Set

0456-132-pattern
1549-longest-continuous-subarray-with-absolute-diff-less-than-or-equal-to-limit
2434-design-a-number-container-system

Greedy

0011-container-with-most-water
0134-gas-station
0179-largest-number
0452-minimum-number-of-arrows-to-burst-balloons
0680-valid-palindrome-ii
0768-partition-labels
0797-rabbits-in-forest
0890-lemonade-change
0917-boats-to-save-people
1009-pancake-sorting
1049-minimum-domino-rotations-for-equal-row
1303-minimum-moves-to-reach-target-score
1341-split-a-string-in-balanced-strings
1683-maximum-number-of-coins-you-can-get
1695-maximum-sum-obtained-of-any-permutation
1961-maximum-ice-cream-bars
2148-minimum-number-of-moves-to-seat-everyone
2180-maximum-number-of-tasks-you-can-assign
2456-construct-smallest-number-from-di-string
3171-minimum-equal-sum-of-two-arrays-after-replacing-zeros
3195-separate-black-and-white-balls

Stack

0020-valid-parentheses
0071-simplify-path
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0225-implement-stack-using-queues
0232-implement-queue-using-stacks
0234-palindrome-linked-list
0394-decode-string
0456-132-pattern
0739-daily-temperatures
0874-backspace-string-compare
0886-score-of-parentheses
0943-sum-of-subarray-minimums
1582-design-browser-history
1720-crawler-log-folder
2021-remove-all-occurrences-of-a-substring
2456-construct-smallest-number-from-di-string
2470-removing-stars-from-a-string
3447-clear-digits

Binary Search

0034-find-first-and-last-position-of-element-in-sorted-array
0069-sqrtx
0074-search-a-2d-matrix
0153-find-minimum-in-rotated-sorted-array
0167-two-sum-ii-input-array-is-sorted
0268-missing-number
0275-h-index-ii
0278-first-bad-version
0456-132-pattern
0475-heaters
0633-sum-of-square-numbers
0792-binary-search
0907-koko-eating-bananas
1046-max-consecutive-ones-iii
1675-magnetic-force-between-two-balls
2180-maximum-number-of-tasks-you-can-assign
2210-find-target-indices-after-sorting-array
2394-count-subarrays-with-score-less-than-k
2614-maximum-count-of-positive-integer-and-negative-integer
2690-house-robber-iv
2699-count-the-number-of-fair-pairs
3643-zero-array-transformation-ii

Merge Sort

0148-sort-list
0948-sort-an-array

Radix Sort

0948-sort-an-array

Counting Sort

0948-sort-an-array
1961-maximum-ice-cream-bars
2148-minimum-number-of-moves-to-seat-everyone

Game Theory

1683-maximum-number-of-coins-you-can-get

Sliding Window

0003-longest-substring-without-repeating-characters
0076-minimum-window-substring
0438-find-all-anagrams-in-a-string
0567-permutation-in-string
0643-maximum-average-subarray-i
0966-binary-subarrays-with-sum
1046-max-consecutive-ones-iii
1538-maximum-points-you-can-obtain-from-cards
1549-longest-continuous-subarray-with-absolute-diff-less-than-or-equal-to-limit
2394-count-subarrays-with-score-less-than-k
2463-minimum-recolors-to-get-k-consecutive-black-blocks
2478-longest-nice-subarray
2527-count-subarrays-with-fixed-bounds
2626-count-the-number-of-good-subarrays
2856-count-complete-subarrays-in-an-array
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
3569-count-of-substrings-containing-every-vowel-and-k-consonants-ii

Prefix Sum

0238-product-of-array-except-self
0303-range-sum-query-immutable
0304-range-sum-query-2d-immutable
0560-subarray-sum-equals-k
0724-find-pivot-index
0966-binary-subarrays-with-sum
1016-subarray-sums-divisible-by-k
1046-max-consecutive-ones-iii
1477-product-of-the-last-k-numbers
1538-maximum-points-you-can-obtain-from-cards
1603-running-sum-of-1d-array
1695-maximum-sum-obtained-of-any-permutation
2249-count-the-hidden-sequences
2394-count-subarrays-with-score-less-than-k
2465-shifting-letters-ii
2915-count-of-interesting-subarrays
3475-minimum-operations-to-make-binary-array-elements-equal-to-one-i
3643-zero-array-transformation-ii

Data Stream

0789-kth-largest-element-in-a-stream
1477-product-of-the-last-k-numbers
1582-design-browser-history

Backtracking

0039-combination-sum
0046-permutations
0077-combinations
0078-subsets
0093-restore-ip-addresses
1160-letter-tile-possibilities
1418-fair-distribution-of-cookies
1516-the-k-th-lexicographical-string-of-all-happy-strings-of-length-n
1819-construct-the-lexicographically-largest-valid-sequence
1976-splitting-a-string-into-descending-consecutive-values
1993-sum-of-all-subset-xor-totals
2456-construct-smallest-number-from-di-string
2802-find-the-punishment-number-of-an-integer

Randomized

0380-insert-delete-getrandom-o1

Dynamic Programming

0053-maximum-subarray
0119-pascals-triangle-ii
0338-counting-bits
0368-largest-divisible-subset
0806-domino-and-tromino-tiling
0868-push-dominoes
0943-sum-of-subarray-minimums
1418-fair-distribution-of-cookies
2090-number-of-ways-to-arrive-at-destination
2415-count-the-number-of-ideal-arrays
3243-count-the-number-of-powerful-integers
3637-count-number-of-balanced-permutations

Line Sweep

1028-interval-list-intersections

Linked List

0019-remove-nth-node-from-end-of-list
0021-merge-two-sorted-lists
0083-remove-duplicates-from-sorted-list
0141-linked-list-cycle
0142-linked-list-cycle-ii
0146-lru-cache
0148-sort-list
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
0838-design-linked-list
0859-design-circular-deque
0908-middle-of-the-linked-list
1582-design-browser-history

Doubly-Linked List

0146-lru-cache
1582-design-browser-history

Tree

0101-symmetric-tree
0103-binary-tree-zigzag-level-order-traversal
0104-maximum-depth-of-binary-tree
0108-convert-sorted-array-to-binary-search-tree
0129-sum-root-to-leaf-numbers
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0235-lowest-common-ancestor-of-a-binary-search-tree
0450-delete-node-in-a-bst
0515-find-largest-value-in-each-tree-row
0690-employee-importance
0784-insert-into-a-binary-search-tree
0789-kth-largest-element-in-a-stream
0925-construct-binary-tree-from-preorder-and-postorder-traversal
1005-univalued-binary-tree
1092-maximum-difference-between-node-and-ancestor
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
1492-time-needed-to-inform-all-employees
2347-count-nodes-equal-to-average-of-subtree
2493-reverse-odd-levels-of-binary-tree

Depth-First Search

0101-symmetric-tree
0104-maximum-depth-of-binary-tree
0129-sum-root-to-leaf-numbers
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0207-course-schedule
0210-course-schedule-ii
0235-lowest-common-ancestor-of-a-binary-search-tree
0515-find-largest-value-in-each-tree-row
0547-number-of-provinces
0690-employee-importance
0695-max-area-of-island
0733-flood-fill
0801-is-graph-bipartite
0820-find-eventual-safe-states
0922-possible-bipartition
1005-univalued-binary-tree
1092-maximum-difference-between-node-and-ancestor
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
1431-all-ancestors-of-a-node-in-a-directed-acyclic-graph
1492-time-needed-to-inform-all-employees
1558-course-schedule-iv
2121-find-if-path-exists-in-graph
2347-count-nodes-equal-to-average-of-subtree
2493-reverse-odd-levels-of-binary-tree

Breadth-First Search

0101-symmetric-tree
0103-binary-tree-zigzag-level-order-traversal
0104-maximum-depth-of-binary-tree
0207-course-schedule
0210-course-schedule-ii
0515-find-largest-value-in-each-tree-row
0547-number-of-provinces
0690-employee-importance
0695-max-area-of-island
0733-flood-fill
0801-is-graph-bipartite
0820-find-eventual-safe-states
0922-possible-bipartition
0945-snakes-and-ladders
1005-univalued-binary-tree
1036-rotting-oranges
1218-lowest-common-ancestor-of-deepest-leaves
1387-find-elements-in-a-contaminated-binary-tree
1431-all-ancestors-of-a-node-in-a-directed-acyclic-graph
1492-time-needed-to-inform-all-employees
1558-course-schedule-iv
2121-find-if-path-exists-in-graph
2493-reverse-odd-levels-of-binary-tree
2588-maximum-number-of-points-from-grid-queries

Binary Tree

0101-symmetric-tree
0103-binary-tree-zigzag-level-order-traversal
0104-maximum-depth-of-binary-tree
0108-convert-sorted-array-to-binary-search-tree
0129-sum-root-to-leaf-numbers
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0235-lowest-common-ancestor-of-a-binary-search-tree
0450-delete-node-in-a-bst
0515-find-largest-value-in-each-tree-row
0784-insert-into-a-binary-search-tree
0789-kth-largest-element-in-a-stream
0925-construct-binary-tree-from-preorder-and-postorder-traversal
1005-univalued-binary-tree
1092-maximum-difference-between-node-and-ancestor
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
2347-count-nodes-equal-to-average-of-subtree
2493-reverse-odd-levels-of-binary-tree

Monotonic Stack

0456-132-pattern
0739-daily-temperatures
0943-sum-of-subarray-minimums

Monotonic Queue

1549-longest-continuous-subarray-with-absolute-diff-less-than-or-equal-to-limit
2180-maximum-number-of-tasks-you-can-assign
2527-count-subarrays-with-fixed-bounds

Binary Search Tree

0108-convert-sorted-array-to-binary-search-tree
0235-lowest-common-ancestor-of-a-binary-search-tree
0450-delete-node-in-a-bst
0784-insert-into-a-binary-search-tree
0789-kth-largest-element-in-a-stream
1114-binary-search-tree-to-greater-sum-tree

Union Find

0547-number-of-provinces
0695-max-area-of-island
0801-is-graph-bipartite
0922-possible-bipartition
2121-find-if-path-exists-in-graph
2588-maximum-number-of-points-from-grid-queries
3348-minimum-cost-walk-in-weighted-graph

Graph

0207-course-schedule
0210-course-schedule-ii
0547-number-of-provinces
0801-is-graph-bipartite
0820-find-eventual-safe-states
0922-possible-bipartition
1431-all-ancestors-of-a-node-in-a-directed-acyclic-graph
1558-course-schedule-iv
2090-number-of-ways-to-arrive-at-destination
2121-find-if-path-exists-in-graph
2220-find-all-possible-recipes-from-given-supplies
3189-find-champion-ii
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

Bitmask

1418-fair-distribution-of-cookies

Topological Sort

0207-course-schedule
0210-course-schedule-ii
0820-find-eventual-safe-states
1431-all-ancestors-of-a-node-in-a-directed-acyclic-graph
1558-course-schedule-iv
2090-number-of-ways-to-arrive-at-destination
2220-find-all-possible-recipes-from-given-supplies

Shortest Path

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

Interactive

0278-first-bad-version

Combinatorics

1993-sum-of-all-subset-xor-totals
2415-count-the-number-of-ideal-arrays
3548-find-the-count-of-good-integers
3637-count-number-of-balanced-permutations

Enumeration

1656-count-good-triplets
1993-sum-of-all-subset-xor-totals
2998-count-symmetric-integers
3548-find-the-count-of-good-integers

Number Theory

2415-count-the-number-of-ideal-arrays