leetcode

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

LeetCode Topics

Linked List

0025-reverse-nodes-in-k-group
0083-remove-duplicates-from-sorted-list
0114-flatten-binary-tree-to-linked-list
0138-copy-list-with-random-pointer
0146-lru-cache
0328-odd-even-linked-list
0460-lfu-cache
0725-split-linked-list-in-parts
0859-design-circular-deque
1484-linked-list-in-binary-tree
2236-maximum-twin-sum-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

Array

0011-container-with-most-water
0034-find-first-and-last-position-of-element-in-sorted-array
0036-valid-sudoku
0039-combination-sum
0040-combination-sum-ii
0041-first-missing-positive
0045-jump-game-ii
0046-permutations
0048-rotate-image
0054-spiral-matrix
0059-spiral-matrix-ii
0066-plus-one
0073-set-matrix-zeroes
0074-search-a-2d-matrix
0075-sort-colors
0079-word-search
0080-remove-duplicates-from-sorted-array-ii
0108-convert-sorted-array-to-binary-search-tree
0118-pascals-triangle
0119-pascals-triangle-ii
0134-gas-station
0135-candy
0139-word-break
0149-max-points-on-a-line
0152-maximum-product-subarray
0162-find-peak-element
0167-two-sum-ii-input-array-is-sorted
0179-largest-number
0198-house-robber
0209-minimum-size-subarray-sum
0215-kth-largest-element-in-an-array
0238-product-of-array-except-self
0239-sliding-window-maximum
0240-search-a-2d-matrix-ii
0283-move-zeroes
0287-find-the-duplicate-number
0329-longest-increasing-path-in-a-matrix
0334-increasing-triplet-subsequence
0347-top-k-frequent-elements
0349-intersection-of-two-arrays
0399-evaluate-division
0410-split-array-largest-sum
0448-find-all-numbers-disappeared-in-an-array
0494-target-sum
0539-minimum-time-difference
0560-subarray-sum-equals-k
0566-reshape-the-matrix
0575-distribute-candies
0605-can-place-flowers
0621-task-scheduler
0624-maximum-distance-in-arrays
0632-smallest-range-covering-elements-from-k-lists
0719-find-k-th-smallest-pair-distance
0724-find-pivot-index
0729-my-calendar-i
0731-my-calendar-ii
0735-asteroid-collision
0739-daily-temperatures
0745-find-smallest-letter-greater-than-target
0747-min-cost-climbing-stairs
0787-sliding-puzzle
0859-design-circular-deque
0876-hand-of-straights
0882-peak-index-in-a-mountain-array
0892-shortest-subarray-with-sum-at-least-k
0898-transpose-matrix
0906-walking-robot-simulation
0907-koko-eating-bananas
0909-stone-game
0917-boats-to-save-people
0921-spiral-matrix-iii
0958-sort-array-by-parity-ii
0985-bag-of-tokens
1002-maximum-width-ramp
1025-minimum-cost-for-tickets
1046-max-consecutive-ones-iii
1056-capacity-to-ship-packages-within-d-days
1063-best-sightseeing-pair
1127-last-stone-weight
1185-find-in-mountain-array
1240-stone-game-ii
1256-rank-transform-of-an-array
1319-unique-number-of-occurrences
1325-path-with-maximum-probability
1346-maximize-the-topmost-element-after-k-moves
1350-remove-sub-folders-from-the-filesystem
1392-find-the-difference-of-two-arrays
1402-count-square-submatrices-with-all-ones
1408-find-the-smallest-divisor-given-a-threshold
1422-divide-array-in-sets-of-k-consecutive-numbers
1428-jump-game-iii
1435-xor-queries-of-a-subarray
1447-jump-game-iv
1466-jump-game-v
1468-check-if-n-and-its-double-exist
1497-design-a-stack-with-increment-operation
1511-count-number-of-teams
1528-kids-with-the-greatest-number-of-candies
1586-longest-subarray-of-1s-after-deleting-one-element
1605-minimum-number-of-days-to-make-m-bouquets
1620-check-if-array-pairs-are-divisible-by-k
1679-shortest-subarray-to-be-removed-to-make-array-sorted
1755-defuse-the-bomb
1786-count-the-number-of-consistent-strings
1798-max-number-of-k-sum-pairs
1814-jump-game-vi
1833-find-the-highest-altitude
1886-minimum-limit-of-balls-in-a-bag
1917-maximum-average-pass-ratio
1923-sentence-similarity-iii
1927-maximum-ascending-subarray-sum
1940-maximum-xor-for-each-query
1972-rotating-the-box
2006-find-the-student-that-will-replace-the-chalk
2035-count-sub-islands
2038-nearest-exit-from-entrance-in-maze
2048-build-array-from-permutation
2049-eliminate-maximum-number-of-monsters
2054-the-number-of-the-smallest-unoccupied-chair
2067-maximum-number-of-points-with-cost
2089-maximum-matrix-sum
2122-count-special-quadruplets
2132-convert-1d-array-into-2d-array
2155-find-missing-observations
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
2232-adding-spaces-to-a-string
2343-count-unguarded-cells-in-the-grid
2356-largest-combination-with-bitwise-and-greater-than-zero
2358-number-of-ways-to-split-array
2375-minimum-obstacle-removal-to-reach-corner
2392-successful-pairs-of-spells-and-potions
2411-spiral-matrix-iv
2421-maximum-number-of-pairs-in-array
2428-equal-row-and-column-pairs
2465-shifting-letters-ii
2472-build-a-matrix-with-conditions
2488-divide-intervals-into-minimum-number-of-groups
2503-longest-subarray-with-maximum-bitwise-and
2545-height-of-binary-tree-after-subtree-removal-queries
2552-maximum-sum-of-distinct-subarrays-with-length-k
2581-divide-players-into-teams-of-equal-skill
2586-longest-square-streak-in-an-array
2616-maximal-score-after-applying-k-operations
2636-maximum-subsequence-score
2640-maximum-number-of-integers-to-choose-from-a-range-i
2661-smallest-missing-non-negative-integer-after-operations
2691-count-vowel-strings-in-ranges
2692-take-gifts-from-the-richest-pile
2699-count-the-number-of-fair-pairs
2711-minimum-time-to-visit-a-cell-in-a-grid
2755-extra-characters-in-a-string
2766-find-the-prefix-common-array-of-two-arrays
2794-maximum-number-of-moves-in-a-grid
2868-continuous-subarrays
2891-maximum-beauty-of-an-array-after-applying-operation
3031-construct-product-matrix
3188-find-champion-i
3291-find-if-array-can-be-sorted
3329-find-the-length-of-the-longest-common-prefix
3380-shortest-subarray-with-or-at-least-k-ii
3381-shortest-subarray-with-or-at-least-k-i
3413-find-the-first-player-to-win-k-games-in-a-row
3415-check-if-grid-satisfies-conditions
3427-special-array-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
3556-final-array-state-after-k-multiplication-operations-ii
3563-select-cells-in-grid-with-maximum-score
3619-adjacent-increasing-subarrays-detection-ii

Matrix

0036-valid-sudoku
0048-rotate-image
0054-spiral-matrix
0059-spiral-matrix-ii
0073-set-matrix-zeroes
0074-search-a-2d-matrix
0079-word-search
0240-search-a-2d-matrix-ii
0329-longest-increasing-path-in-a-matrix
0566-reshape-the-matrix
0787-sliding-puzzle
0898-transpose-matrix
0921-spiral-matrix-iii
1402-count-square-submatrices-with-all-ones
1972-rotating-the-box
2035-count-sub-islands
2038-nearest-exit-from-entrance-in-maze
2089-maximum-matrix-sum
2132-convert-1d-array-into-2d-array
2343-count-unguarded-cells-in-the-grid
2375-minimum-obstacle-removal-to-reach-corner
2411-spiral-matrix-iv
2428-equal-row-and-column-pairs
2472-build-a-matrix-with-conditions
2711-minimum-time-to-visit-a-cell-in-a-grid
2794-maximum-number-of-moves-in-a-grid
3031-construct-product-matrix
3188-find-champion-i
3415-check-if-grid-satisfies-conditions
3563-select-cells-in-grid-with-maximum-score

Simulation

0054-spiral-matrix
0059-spiral-matrix-ii
0566-reshape-the-matrix
0592-fraction-addition-and-subtraction
0735-asteroid-collision
0898-transpose-matrix
0906-walking-robot-simulation
0921-spiral-matrix-iii
1667-find-kth-bit-in-nth-binary-string
2006-find-the-student-that-will-replace-the-chalk
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
2343-count-unguarded-cells-in-the-grid
2411-spiral-matrix-iv
2428-equal-row-and-column-pairs
2470-removing-stars-from-a-string
2692-take-gifts-from-the-richest-pile
2800-minimum-string-length-after-removing-substrings
3413-find-the-first-player-to-win-k-games-in-a-row
3555-final-array-state-after-k-multiplication-operations-i
3556-final-array-state-after-k-multiplication-operations-ii

Divide and Conquer

0108-convert-sorted-array-to-binary-search-tree
0215-kth-largest-element-in-an-array
0240-search-a-2d-matrix-ii
0347-top-k-frequent-elements

Sorting

0075-sort-colors
0179-largest-number
0215-kth-largest-element-in-an-array
0295-find-median-from-data-stream
0347-top-k-frequent-elements
0349-intersection-of-two-arrays
0451-sort-characters-by-frequency
0539-minimum-time-difference
0621-task-scheduler
0632-smallest-range-covering-elements-from-k-lists
0719-find-k-th-smallest-pair-distance
0876-hand-of-straights
0917-boats-to-save-people
0958-sort-array-by-parity-ii
0985-bag-of-tokens
1256-rank-transform-of-an-array
1422-divide-array-in-sets-of-k-consecutive-numbers
1466-jump-game-v
1468-check-if-n-and-its-double-exist
1777-determine-if-two-strings-are-close
1798-max-number-of-k-sum-pairs
2049-eliminate-maximum-number-of-monsters
2164-two-best-non-overlapping-events
2179-most-beautiful-item-for-each-query
2392-successful-pairs-of-spells-and-potions
2488-divide-intervals-into-minimum-number-of-groups
2581-divide-players-into-teams-of-equal-skill
2586-longest-square-streak-in-an-array
2636-maximum-subsequence-score
2640-maximum-number-of-integers-to-choose-from-a-range-i
2646-kth-largest-sum-in-a-binary-tree
2699-count-the-number-of-fair-pairs
2891-maximum-beauty-of-an-array-after-applying-operation
3291-find-if-array-can-be-sorted

Heap (Priority Queue)

0215-kth-largest-element-in-an-array
0239-sliding-window-maximum
0264-ugly-number-ii
0295-find-median-from-data-stream
0347-top-k-frequent-elements
0451-sort-characters-by-frequency
0621-task-scheduler
0632-smallest-range-covering-elements-from-k-lists
0789-kth-largest-element-in-a-stream
0892-shortest-subarray-with-sum-at-least-k
1127-last-stone-weight
1304-longest-happy-string
1325-path-with-maximum-probability
1814-jump-game-vi
1917-maximum-average-pass-ratio
2054-the-number-of-the-smallest-unoccupied-chair
2164-two-best-non-overlapping-events
2375-minimum-obstacle-removal-to-reach-corner
2413-smallest-number-in-infinite-set
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
2711-minimum-time-to-visit-a-cell-in-a-grid
2803-modify-graph-edge-weights
2868-continuous-subarrays
3555-final-array-state-after-k-multiplication-operations-i
3556-final-array-state-after-k-multiplication-operations-ii

Quickselect

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

Hash Table

0017-letter-combinations-of-a-phone-number
0036-valid-sudoku
0041-first-missing-positive
0073-set-matrix-zeroes
0138-copy-list-with-random-pointer
0139-word-break
0146-lru-cache
0149-max-points-on-a-line
0205-isomorphic-strings
0264-ugly-number-ii
0347-top-k-frequent-elements
0349-intersection-of-two-arrays
0424-longest-repeating-character-replacement
0448-find-all-numbers-disappeared-in-an-array
0451-sort-characters-by-frequency
0460-lfu-cache
0560-subarray-sum-equals-k
0567-permutation-in-string
0575-distribute-candies
0621-task-scheduler
0632-smallest-range-covering-elements-from-k-lists
0768-partition-labels
0876-hand-of-straights
0906-walking-robot-simulation
0920-uncommon-words-from-two-sentences
0984-most-stones-removed-with-same-row-or-column
1256-rank-transform-of-an-array
1319-unique-number-of-occurrences
1392-find-the-difference-of-two-arrays
1422-divide-array-in-sets-of-k-consecutive-numbers
1447-jump-game-iv
1468-check-if-n-and-its-double-exist
1469-minimum-number-of-steps-to-make-two-strings-anagram
1473-find-the-longest-substring-containing-vowels-in-even-counts
1620-check-if-array-pairs-are-divisible-by-k
1777-determine-if-two-strings-are-close
1786-count-the-number-of-consistent-strings
1798-max-number-of-k-sum-pairs
2054-the-number-of-the-smallest-unoccupied-chair
2059-unique-length-3-palindromic-subsequences
2122-count-special-quadruplets
2356-largest-combination-with-bitwise-and-greater-than-zero
2413-smallest-number-in-infinite-set
2421-maximum-number-of-pairs-in-array
2427-first-letter-to-appear-twice
2428-equal-row-and-column-pairs
2552-maximum-sum-of-distinct-subarrays-with-length-k
2581-divide-players-into-teams-of-equal-skill
2586-longest-square-streak-in-an-array
2640-maximum-number-of-integers-to-choose-from-a-range-i
2661-smallest-missing-non-negative-integer-after-operations
2677-cousins-in-binary-tree-ii
2755-extra-characters-in-a-string
2766-find-the-prefix-common-array-of-two-arrays
3329-find-the-length-of-the-longest-common-prefix
3408-count-the-number-of-special-characters-i
3501-delete-nodes-from-linked-list-present-in-array

Greedy

0011-container-with-most-water
0045-jump-game-ii
0134-gas-station
0135-candy
0179-largest-number
0334-increasing-triplet-subsequence
0410-split-array-largest-sum
0605-can-place-flowers
0621-task-scheduler
0624-maximum-distance-in-arrays
0632-smallest-range-covering-elements-from-k-lists
0649-dota2-senate
0670-maximum-swap
0678-valid-parenthesis-string
0768-partition-labels
0876-hand-of-straights
0917-boats-to-save-people
0957-minimum-add-to-make-parentheses-valid
0985-bag-of-tokens
1033-broken-calculator
1252-break-a-palindrome
1304-longest-happy-string
1346-maximize-the-topmost-element-after-k-moves
1422-divide-array-in-sets-of-k-consecutive-numbers
1917-maximum-average-pass-ratio
2049-eliminate-maximum-number-of-monsters
2089-maximum-matrix-sum
2095-minimum-number-of-swaps-to-make-the-string-balanced
2488-divide-intervals-into-minimum-number-of-groups
2616-maximal-score-after-applying-k-operations
2636-maximum-subsequence-score
2640-maximum-number-of-integers-to-choose-from-a-range-i
2661-smallest-missing-non-negative-integer-after-operations
3195-separate-black-and-white-balls

Counting

0347-top-k-frequent-elements
0451-sort-characters-by-frequency
0621-task-scheduler
0920-uncommon-words-from-two-sentences
1469-minimum-number-of-steps-to-make-two-strings-anagram
1620-check-if-array-pairs-are-divisible-by-k
1777-determine-if-two-strings-are-close
1786-count-the-number-of-consistent-strings
2356-largest-combination-with-bitwise-and-greater-than-zero
2421-maximum-number-of-pairs-in-array
2427-first-letter-to-appear-twice

String

0005-longest-palindromic-substring
0006-zigzag-conversion
0014-longest-common-prefix
0017-letter-combinations-of-a-phone-number
0028-find-the-index-of-the-first-occurrence-in-a-string
0032-longest-valid-parentheses
0038-count-and-say
0079-word-search
0139-word-break
0151-reverse-words-in-a-string
0179-largest-number
0205-isomorphic-strings
0241-different-ways-to-add-parentheses
0301-remove-invalid-parentheses
0345-reverse-vowels-of-a-string
0392-is-subsequence
0394-decode-string
0399-evaluate-division
0424-longest-repeating-character-replacement
0443-string-compression
0451-sort-characters-by-frequency
0539-minimum-time-difference
0564-find-the-closest-palindrome
0567-permutation-in-string
0592-fraction-addition-and-subtraction
0649-dota2-senate
0678-valid-parenthesis-string
0768-partition-labels
0920-uncommon-words-from-two-sentences
0957-minimum-add-to-make-parentheses-valid
1128-remove-all-adjacent-duplicates-in-string
1146-greatest-common-divisor-of-strings
1197-parsing-a-boolean-expression
1252-break-a-palindrome
1302-delete-characters-to-make-fancy-string
1304-longest-happy-string
1320-remove-all-adjacent-duplicates-in-string-ii
1350-remove-sub-folders-from-the-filesystem
1469-minimum-number-of-steps-to-make-two-strings-anagram
1473-find-the-longest-substring-containing-vowels-in-even-counts
1537-maximum-score-after-splitting-a-string
1566-check-if-a-word-occurs-as-a-prefix-of-any-word-in-a-sentence
1567-maximum-number-of-vowels-in-a-substring-of-given-length
1667-find-kth-bit-in-nth-binary-string
1777-determine-if-two-strings-are-close
1786-count-the-number-of-consistent-strings
1894-merge-strings-alternately
1923-sentence-similarity-iii
2059-unique-length-3-palindromic-subsequences
2076-sum-of-digits-of-string-after-convert
2095-minimum-number-of-swaps-to-make-the-string-balanced
2232-adding-spaces-to-a-string
2414-move-pieces-to-obtain-a-string
2427-first-letter-to-appear-twice
2465-shifting-letters-ii
2470-removing-stars-from-a-string
2580-circular-sentence
2691-count-vowel-strings-in-ranges
2755-extra-characters-in-a-string
2800-minimum-string-length-after-removing-substrings
3018-make-string-a-subsequence-using-cyclic-increments
3174-minimum-number-of-changes-to-make-binary-string-beautiful
3195-separate-black-and-white-balls
3329-find-the-length-of-the-longest-common-prefix
3408-count-the-number-of-special-characters-i
3451-string-compression-iii

Backtracking

0017-letter-combinations-of-a-phone-number
0039-combination-sum
0040-combination-sum-ii
0046-permutations
0079-word-search
0113-path-sum-ii
0301-remove-invalid-parentheses
0494-target-sum
2170-count-number-of-maximum-bitwise-or-subsets

Tree

0104-maximum-depth-of-binary-tree
0108-convert-sorted-array-to-binary-search-tree
0112-path-sum
0113-path-sum-ii
0114-flatten-binary-tree-to-linked-list
0145-binary-tree-postorder-traversal
0236-lowest-common-ancestor-of-a-binary-tree
0437-path-sum-iii
0515-find-largest-value-in-each-tree-row
0776-n-ary-tree-postorder-traversal
0783-search-in-a-binary-search-tree
0789-kth-largest-element-in-a-stream
0904-leaf-similar-trees
0988-flip-equivalent-binary-trees
1035-cousins-in-binary-tree
1116-maximum-level-sum-of-a-binary-tree
1474-longest-zigzag-path-in-a-binary-tree
1484-linked-list-in-binary-tree
1544-count-good-nodes-in-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

Design

0146-lru-cache
0295-find-median-from-data-stream
0460-lfu-cache
0729-my-calendar-i
0731-my-calendar-ii
0789-kth-largest-element-in-a-stream
0859-design-circular-deque
0969-number-of-recent-calls
1497-design-a-stack-with-increment-operation
2413-smallest-number-in-infinite-set

Binary Search Tree

0034-find-first-and-last-position-of-element-in-sorted-array
0074-search-a-2d-matrix
0108-convert-sorted-array-to-binary-search-tree
0162-find-peak-element
0167-two-sum-ii-input-array-is-sorted
0209-minimum-size-subarray-sum
0240-search-a-2d-matrix-ii
0287-find-the-duplicate-number
0349-intersection-of-two-arrays
0374-guess-number-higher-or-lower
0410-split-array-largest-sum
0719-find-k-th-smallest-pair-distance
0729-my-calendar-i
0731-my-calendar-ii
0745-find-smallest-letter-greater-than-target
0783-search-in-a-binary-search-tree
0789-kth-largest-element-in-a-stream
0882-peak-index-in-a-mountain-array
0892-shortest-subarray-with-sum-at-least-k
0907-koko-eating-bananas
1046-max-consecutive-ones-iii
1056-capacity-to-ship-packages-within-d-days
1185-find-in-mountain-array
1408-find-the-smallest-divisor-given-a-threshold
1468-check-if-n-and-its-double-exist
1605-minimum-number-of-days-to-make-m-bouquets
1679-shortest-subarray-to-be-removed-to-make-array-sorted
1886-minimum-limit-of-balls-in-a-bag
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
2392-successful-pairs-of-spells-and-potions
2586-longest-square-streak-in-an-array
2640-maximum-number-of-integers-to-choose-from-a-range-i
2699-count-the-number-of-fair-pairs
2891-maximum-beauty-of-an-array-after-applying-operation
3427-special-array-ii
3619-adjacent-increasing-subarrays-detection-ii

Binary Tree

0104-maximum-depth-of-binary-tree
0108-convert-sorted-array-to-binary-search-tree
0112-path-sum
0113-path-sum-ii
0114-flatten-binary-tree-to-linked-list
0145-binary-tree-postorder-traversal
0236-lowest-common-ancestor-of-a-binary-tree
0437-path-sum-iii
0515-find-largest-value-in-each-tree-row
0783-search-in-a-binary-search-tree
0789-kth-largest-element-in-a-stream
0904-leaf-similar-trees
0988-flip-equivalent-binary-trees
1035-cousins-in-binary-tree
1116-maximum-level-sum-of-a-binary-tree
1474-longest-zigzag-path-in-a-binary-tree
1484-linked-list-in-binary-tree
1544-count-good-nodes-in-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

Data Stream

0295-find-median-from-data-stream
0789-kth-largest-element-in-a-stream
0969-number-of-recent-calls

Dynamic Programming

0005-longest-palindromic-substring
0032-longest-valid-parentheses
0045-jump-game-ii
0118-pascals-triangle
0119-pascals-triangle-ii
0139-word-break
0152-maximum-product-subarray
0198-house-robber
0241-different-ways-to-add-parentheses
0264-ugly-number-ii
0279-perfect-squares
0329-longest-increasing-path-in-a-matrix
0392-is-subsequence
0410-split-array-largest-sum
0494-target-sum
0650-2-keys-keyboard
0678-valid-parenthesis-string
0747-min-cost-climbing-stairs
0909-stone-game
1025-minimum-cost-for-tickets
1063-best-sightseeing-pair
1236-n-th-tribonacci-number
1240-stone-game-ii
1402-count-square-submatrices-with-all-ones
1466-jump-game-v
1474-longest-zigzag-path-in-a-binary-tree
1511-count-number-of-teams
1586-longest-subarray-of-1s-after-deleting-one-element
1814-jump-game-vi
2067-maximum-number-of-points-with-cost
2164-two-best-non-overlapping-events
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
3563-select-cells-in-grid-with-maximum-score

Stack

0032-longest-valid-parentheses
0114-flatten-binary-tree-to-linked-list
0145-binary-tree-postorder-traversal
0394-decode-string
0678-valid-parenthesis-string
0735-asteroid-collision
0739-daily-temperatures
0776-n-ary-tree-postorder-traversal
0957-minimum-add-to-make-parentheses-valid
1002-maximum-width-ramp
1128-remove-all-adjacent-duplicates-in-string
1197-parsing-a-boolean-expression
1320-remove-all-adjacent-duplicates-in-string-ii
1497-design-a-stack-with-increment-operation
1679-shortest-subarray-to-be-removed-to-make-array-sorted
2095-minimum-number-of-swaps-to-make-the-string-balanced
2236-maximum-twin-sum-of-a-linked-list
2470-removing-stars-from-a-string
2800-minimum-string-length-after-removing-substrings

Doubly-Linked List

0146-lru-cache
0460-lfu-cache

Two Pointers

0005-longest-palindromic-substring
0011-container-with-most-water
0028-find-the-index-of-the-first-occurrence-in-a-string
0075-sort-colors
0080-remove-duplicates-from-sorted-array-ii
0151-reverse-words-in-a-string
0167-two-sum-ii-input-array-is-sorted
0283-move-zeroes
0287-find-the-duplicate-number
0295-find-median-from-data-stream
0345-reverse-vowels-of-a-string
0349-intersection-of-two-arrays
0392-is-subsequence
0443-string-compression
0567-permutation-in-string
0719-find-k-th-smallest-pair-distance
0768-partition-labels
0917-boats-to-save-people
0958-sort-array-by-parity-ii
0985-bag-of-tokens
1468-check-if-n-and-its-double-exist
1566-check-if-a-word-occurs-as-a-prefix-of-any-word-in-a-sentence
1679-shortest-subarray-to-be-removed-to-make-array-sorted
1798-max-number-of-k-sum-pairs
1894-merge-strings-alternately
1923-sentence-similarity-iii
1972-rotating-the-box
2095-minimum-number-of-swaps-to-make-the-string-balanced
2232-adding-spaces-to-a-string
2236-maximum-twin-sum-of-a-linked-list
2392-successful-pairs-of-spells-and-potions
2414-move-pieces-to-obtain-a-string
2488-divide-intervals-into-minimum-number-of-groups
2581-divide-players-into-teams-of-equal-skill
2699-count-the-number-of-fair-pairs
3018-make-string-a-subsequence-using-cyclic-increments
3195-separate-black-and-white-balls

Depth-First Search

0104-maximum-depth-of-binary-tree
0112-path-sum
0113-path-sum-ii
0114-flatten-binary-tree-to-linked-list
0145-binary-tree-postorder-traversal
0236-lowest-common-ancestor-of-a-binary-tree
0329-longest-increasing-path-in-a-matrix
0386-lexicographical-numbers
0399-evaluate-division
0437-path-sum-iii
0515-find-largest-value-in-each-tree-row
0776-n-ary-tree-postorder-traversal
0820-find-eventual-safe-states
0871-keys-and-rooms
0904-leaf-similar-trees
0984-most-stones-removed-with-same-row-or-column
0988-flip-equivalent-binary-trees
1035-cousins-in-binary-tree
1116-maximum-level-sum-of-a-binary-tree
1350-remove-sub-folders-from-the-filesystem
1428-jump-game-iii
1474-longest-zigzag-path-in-a-binary-tree
1484-linked-list-in-binary-tree
1544-count-good-nodes-in-binary-tree
1576-reorder-routes-to-make-all-paths-lead-to-the-city-zero
2035-count-sub-islands
2545-height-of-binary-tree-after-subtree-removal-queries
2677-cousins-in-binary-tree-ii

Breadth-First Search

0104-maximum-depth-of-binary-tree
0112-path-sum
0279-perfect-squares
0301-remove-invalid-parentheses
0329-longest-increasing-path-in-a-matrix
0399-evaluate-division
0515-find-largest-value-in-each-tree-row
0787-sliding-puzzle
0820-find-eventual-safe-states
0871-keys-and-rooms
1035-cousins-in-binary-tree
1116-maximum-level-sum-of-a-binary-tree
1428-jump-game-iii
1447-jump-game-iv
1484-linked-list-in-binary-tree
1544-count-good-nodes-in-binary-tree
1576-reorder-routes-to-make-all-paths-lead-to-the-city-zero
2035-count-sub-islands
2038-nearest-exit-from-entrance-in-maze
2375-minimum-obstacle-removal-to-reach-corner
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
3517-shortest-distance-after-road-addition-queries-i

Queue

0239-sliding-window-maximum
0649-dota2-senate
0859-design-circular-deque
0892-shortest-subarray-with-sum-at-least-k
0969-number-of-recent-calls
1814-jump-game-vi
2868-continuous-subarrays

Monotonic Queue

0239-sliding-window-maximum
0892-shortest-subarray-with-sum-at-least-k
1814-jump-game-vi
2868-continuous-subarrays

Bit Manipulation

0287-find-the-duplicate-number
0405-convert-a-number-to-hexadecimal
0476-number-complement
1435-xor-queries-of-a-subarray
1473-find-the-longest-substring-containing-vowels-in-even-counts
1786-count-the-number-of-consistent-strings
1940-maximum-xor-for-each-query
2059-unique-length-3-palindromic-subsequences
2170-count-number-of-maximum-bitwise-or-subsets
2323-minimum-bit-flips-to-convert-number
2356-largest-combination-with-bitwise-and-greater-than-zero
2427-first-letter-to-appear-twice
2503-longest-subarray-with-maximum-bitwise-and
2766-find-the-prefix-common-array-of-two-arrays
3291-find-if-array-can-be-sorted
3380-shortest-subarray-with-or-at-least-k-ii
3381-shortest-subarray-with-or-at-least-k-i
3394-minimum-array-end
3563-select-cells-in-grid-with-maximum-score

Math

0048-rotate-image
0066-plus-one
0149-max-points-on-a-line
0241-different-ways-to-add-parentheses
0263-ugly-number
0264-ugly-number-ii
0279-perfect-squares
0405-convert-a-number-to-hexadecimal
0539-minimum-time-difference
0564-find-the-closest-palindrome
0592-fraction-addition-and-subtraction
0650-2-keys-keyboard
0670-maximum-swap
0909-stone-game
1033-broken-calculator
1146-greatest-common-divisor-of-strings
1236-n-th-tribonacci-number
1240-stone-game-ii
2155-find-missing-observations
2661-smallest-missing-non-negative-integer-after-operations
2903-insert-greatest-common-divisors-in-linked-list
3555-final-array-state-after-k-multiplication-operations-i

Sliding Window

0209-minimum-size-subarray-sum
0239-sliding-window-maximum
0424-longest-repeating-character-replacement
0567-permutation-in-string
0632-smallest-range-covering-elements-from-k-lists
0892-shortest-subarray-with-sum-at-least-k
1046-max-consecutive-ones-iii
1567-maximum-number-of-vowels-in-a-substring-of-given-length
1586-longest-subarray-of-1s-after-deleting-one-element
1755-defuse-the-bomb
2552-maximum-sum-of-distinct-subarrays-with-length-k
2868-continuous-subarrays
2891-maximum-beauty-of-an-array-after-applying-operation
3380-shortest-subarray-with-or-at-least-k-ii
3381-shortest-subarray-with-or-at-least-k-i
3522-find-the-power-of-k-size-subarrays-i

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
0731-my-calendar-ii
0892-shortest-subarray-with-sum-at-least-k
1046-max-consecutive-ones-iii
1240-stone-game-ii
1435-xor-queries-of-a-subarray
1473-find-the-longest-substring-containing-vowels-in-even-counts
1537-maximum-score-after-splitting-a-string
1833-find-the-highest-altitude
1940-maximum-xor-for-each-query
2006-find-the-student-that-will-replace-the-chalk
2059-unique-length-3-palindromic-subsequences
2358-number-of-ways-to-split-array
2465-shifting-letters-ii
2488-divide-intervals-into-minimum-number-of-groups
2691-count-vowel-strings-in-ranges
3031-construct-product-matrix
3427-special-array-ii

Game Theory

0909-stone-game
1240-stone-game-ii

Trie

0014-longest-common-prefix
0139-word-break
0386-lexicographical-numbers
1350-remove-sub-folders-from-the-filesystem
2755-extra-characters-in-a-string
3329-find-the-length-of-the-longest-common-prefix

Recursion

0025-reverse-nodes-in-k-group
0241-different-ways-to-add-parentheses
0394-decode-string
1197-parsing-a-boolean-expression
1667-find-kth-bit-in-nth-binary-string

Memoization

0139-word-break
0241-different-ways-to-add-parentheses
0329-longest-increasing-path-in-a-matrix
1236-n-th-tribonacci-number

Graph

0329-longest-increasing-path-in-a-matrix
0399-evaluate-division
0820-find-eventual-safe-states
0871-keys-and-rooms
0984-most-stones-removed-with-same-row-or-column
1325-path-with-maximum-probability
1576-reorder-routes-to-make-all-paths-lead-to-the-city-zero
2375-minimum-obstacle-removal-to-reach-corner
2472-build-a-matrix-with-conditions
2711-minimum-time-to-visit-a-cell-in-a-grid
2803-modify-graph-edge-weights
3189-find-champion-ii
3517-shortest-distance-after-road-addition-queries-i

Topological Sort

0329-longest-increasing-path-in-a-matrix
0820-find-eventual-safe-states
2472-build-a-matrix-with-conditions

Bucket Sort

0347-top-k-frequent-elements
0451-sort-characters-by-frequency

Shortest Path

0399-evaluate-division
1325-path-with-maximum-probability
2375-minimum-obstacle-removal-to-reach-corner
2711-minimum-time-to-visit-a-cell-in-a-grid
2803-modify-graph-edge-weights

Union Find

0399-evaluate-division
0984-most-stones-removed-with-same-row-or-column
2035-count-sub-islands

Interactive

0374-guess-number-higher-or-lower
1185-find-in-mountain-array

Binary Indexed Tree

1511-count-number-of-teams

Segment Tree

0729-my-calendar-i
0731-my-calendar-ii
1511-count-number-of-teams

Enumeration

2122-count-special-quadruplets
2170-count-number-of-maximum-bitwise-or-subsets

Number Theory

2903-insert-greatest-common-divisors-in-linked-list

Brainteaser

2503-longest-subarray-with-maximum-bitwise-and

Geometry

0149-max-points-on-a-line

Bitmask

3563-select-cells-in-grid-with-maximum-score

String Matching

0028-find-the-index-of-the-first-occurrence-in-a-string
1566-check-if-a-word-occurs-as-a-prefix-of-any-word-in-a-sentence

Ordered Set

0729-my-calendar-i
0731-my-calendar-ii
2868-continuous-subarrays

Monotonic Stack

0739-daily-temperatures
1002-maximum-width-ramp
1679-shortest-subarray-to-be-removed-to-make-array-sorted