DSALeetCode

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

LeetCode Topics

String

0003-longest-substring-without-repeating-characters
0008-string-to-integer-atoi
0013-roman-to-integer
0017-letter-combinations-of-a-phone-number
0022-generate-parentheses
0044-wildcard-matching
0072-edit-distance
0076-minimum-window-substring
0079-word-search
0115-distinct-subsequences
0127-word-ladder
0131-palindrome-partitioning
0139-word-break
0151-reverse-words-in-a-string
0179-largest-number
0214-shortest-palindrome
0241-different-ways-to-add-parentheses
0242-valid-anagram
0273-integer-to-english-words
0282-expression-add-operators
0297-serialize-and-deserialize-binary-tree
0402-remove-k-digits
0424-longest-repeating-character-replacement
0451-sort-characters-by-frequency
0539-minimum-time-difference
0564-find-the-closest-palindrome
0567-permutation-in-string
0592-fraction-addition-and-subtraction
0664-strange-printer
0812-rotate-string
0920-uncommon-words-from-two-sentences
0957-minimum-add-to-make-parentheses-valid
1197-parsing-a-boolean-expression
1302-delete-characters-to-make-fancy-string
1304-longest-happy-string
1350-remove-sub-folders-from-the-filesystem
1460-number-of-substrings-containing-all-three-characters
1473-find-the-longest-substring-containing-vowels-in-even-counts
1667-find-kth-bit-in-nth-binary-string
1715-split-a-string-into-the-max-number-of-unique-substrings
1737-maximum-nesting-depth-of-the-parentheses
1756-minimum-deletions-to-make-string-balanced
1786-count-the-number-of-consistent-strings
1890-sum-of-beauty-of-all-substrings
1915-check-if-one-string-swap-can-make-strings-equal
1923-sentence-similarity-iii
2076-sum-of-digits-of-string-after-convert
2095-minimum-number-of-swaps-to-make-the-string-balanced
2163-kth-distinct-string-in-an-array
2494-sum-of-prefix-scores-of-strings
2502-sort-the-people
2580-circular-sentence
2727-number-of-senior-citizens
2755-extra-characters-in-a-string
2800-minimum-string-length-after-removing-substrings
3174-minimum-number-of-changes-to-make-binary-string-beautiful
3195-separate-black-and-white-balls
3235-minimum-cost-to-convert-string-i
3276-minimum-number-of-pushes-to-type-word-ii
3329-find-the-length-of-the-longest-common-prefix
3451-string-compression-iii
3567-convert-date-to-binary

Dynamic Programming

0022-generate-parentheses
0044-wildcard-matching
0053-maximum-subarray
0055-jump-game
0072-edit-distance
0115-distinct-subsequences
0118-pascals-triangle
0121-best-time-to-buy-and-sell-stock
0124-binary-tree-maximum-path-sum
0131-palindrome-partitioning
0139-word-break
0152-maximum-product-subarray
0241-different-ways-to-add-parentheses
0264-ugly-number-ii
0410-split-array-largest-sum
0435-non-overlapping-intervals
0542-01-matrix
0650-2-keys-keyboard
0664-strange-printer
0803-cheapest-flights-within-k-stops
0943-sum-of-subarray-minimums
1196-filling-bookcase-shelves
1240-stone-game-ii
1402-count-square-submatrices-with-all-ones
1456-find-the-city-with-the-smallest-number-of-neighbors-at-a-threshold-distance
1511-count-number-of-teams
1756-minimum-deletions-to-make-string-balanced
1766-minimum-number-of-removals-to-make-mountain-array
2067-maximum-number-of-points-with-cost
2090-number-of-ways-to-arrive-at-destination
2586-longest-square-streak-in-an-array
2755-extra-characters-in-a-string
2794-maximum-number-of-moves-in-a-grid
3518-maximum-multiplication-score

Array

0001-two-sum
0015-3sum
0018-4sum
0026-remove-duplicates-from-sorted-array
0031-next-permutation
0033-search-in-rotated-sorted-array
0034-find-first-and-last-position-of-element-in-sorted-array
0035-search-insert-position
0037-sudoku-solver
0039-combination-sum
0040-combination-sum-ii
0048-rotate-image
0051-n-queens
0053-maximum-subarray
0054-spiral-matrix
0055-jump-game
0056-merge-intervals
0057-insert-interval
0073-set-matrix-zeroes
0075-sort-colors
0078-subsets
0079-word-search
0081-search-in-rotated-sorted-array-ii
0084-largest-rectangle-in-histogram
0088-merge-sorted-array
0090-subsets-ii
0105-construct-binary-tree-from-preorder-and-inorder-traversal
0106-construct-binary-tree-from-inorder-and-postorder-traversal
0118-pascals-triangle
0121-best-time-to-buy-and-sell-stock
0128-longest-consecutive-sequence
0130-surrounded-regions
0135-candy
0139-word-break
0152-maximum-product-subarray
0153-find-minimum-in-rotated-sorted-array
0162-find-peak-element
0169-majority-element
0179-largest-number
0189-rotate-array
0215-kth-largest-element-in-an-array
0216-combination-sum-iii
0229-majority-element-ii
0268-missing-number
0283-move-zeroes
0347-top-k-frequent-elements
0373-find-k-pairs-with-smallest-sums
0410-split-array-largest-sum
0435-non-overlapping-intervals
0455-assign-cookies
0485-max-consecutive-ones
0493-reverse-pairs
0539-minimum-time-difference
0540-single-element-in-a-sorted-array
0542-01-matrix
0560-subarray-sum-equals-k
0621-task-scheduler
0624-maximum-distance-in-arrays
0632-smallest-range-covering-elements-from-k-lists
0719-find-k-th-smallest-pair-distance
0729-my-calendar-i
0731-my-calendar-ii
0733-flood-fill
0735-asteroid-collision
0859-design-circular-deque
0870-magic-squares-in-grid
0876-hand-of-straights
0890-lemonade-change
0892-shortest-subarray-with-sum-at-least-k
0906-walking-robot-simulation
0907-koko-eating-bananas
0921-spiral-matrix-iii
0943-sum-of-subarray-minimums
0948-sort-an-array
0966-binary-subarrays-with-sum
0999-regions-cut-by-slashes
1002-maximum-width-ramp
1034-subarrays-with-k-different-integers
1036-rotting-oranges
1046-max-consecutive-ones-iii
1050-construct-binary-search-tree-from-preorder-traversal
1056-capacity-to-ship-packages-within-d-days
1073-number-of-enclaves
1171-shortest-path-in-binary-matrix
1196-filling-bookcase-shelves
1207-delete-nodes-and-return-forest
1227-number-of-equivalent-domino-pairs
1240-stone-game-ii
1256-rank-transform-of-an-array
1325-path-with-maximum-probability
1333-sort-the-jumbled-numbers
1350-remove-sub-folders-from-the-filesystem
1370-count-number-of-nice-subarrays
1402-count-square-submatrices-with-all-ones
1408-find-the-smallest-divisor-given-a-threshold
1421-find-numbers-with-even-number-of-digits
1435-xor-queries-of-a-subarray
1468-check-if-n-and-its-double-exist
1496-lucky-numbers-in-a-matrix
1497-design-a-stack-with-increment-operation
1511-count-number-of-teams
1538-maximum-points-you-can-obtain-from-cards
1556-make-two-arrays-equal-by-reversing-subarrays
1605-minimum-number-of-days-to-make-m-bouquets
1615-range-sum-of-sorted-subarray-sums
1620-check-if-array-pairs-are-divisible-by-k
1646-kth-missing-positive-number
1679-shortest-subarray-to-be-removed-to-make-array-sorted
1691-minimum-number-of-days-to-disconnect-island
1694-make-sum-divisible-by-p
1711-find-valid-matrix-given-row-and-column-sums
1741-sort-array-by-increasing-frequency
1753-path-with-minimum-effort
1755-defuse-the-bomb
1766-minimum-number-of-removals-to-make-mountain-array
1786-count-the-number-of-consistent-strings
1876-map-of-highest-peak
1878-check-if-array-is-sorted-and-rotated
1923-sentence-similarity-iii
1927-maximum-ascending-subarray-sum
2006-find-the-student-that-will-replace-the-chalk
2035-count-sub-islands
2048-build-array-from-permutation
2054-the-number-of-the-smallest-unoccupied-chair
2067-maximum-number-of-points-with-cost
2132-convert-1d-array-into-2d-array
2145-grid-game
2155-find-missing-observations
2163-kth-distinct-string-in-an-array
2170-count-number-of-maximum-bitwise-or-subsets
2179-most-beautiful-item-for-each-query
2188-minimized-maximum-of-products-distributed-to-any-store
2227-sum-of-subarray-ranges
2255-minimum-swaps-to-group-all-1s-together-ii
2271-rearrange-array-elements-by-sign
2356-largest-combination-with-bitwise-and-greater-than-zero
2411-spiral-matrix-iv
2472-build-a-matrix-with-conditions
2488-divide-intervals-into-minimum-number-of-groups
2494-sum-of-prefix-scores-of-strings
2502-sort-the-people
2503-longest-subarray-with-maximum-bitwise-and
2533-bitwise-xor-of-all-pairings
2545-height-of-binary-tree-after-subtree-removal-queries
2581-divide-players-into-teams-of-equal-skill
2586-longest-square-streak-in-an-array
2616-maximal-score-after-applying-k-operations
2685-first-completely-painted-row-or-column
2699-count-the-number-of-fair-pairs
2716-prime-subtraction-operation
2727-number-of-senior-citizens
2755-extra-characters-in-a-string
2766-find-the-prefix-common-array-of-two-arrays
2792-neighboring-bitwise-xor
2794-maximum-number-of-moves-in-a-grid
3171-minimum-equal-sum-of-two-arrays-after-replacing-zeros
3235-minimum-cost-to-convert-string-i
3291-find-if-array-can-be-sorted
3329-find-the-length-of-the-longest-common-prefix
3372-longest-strictly-increasing-or-strictly-decreasing-subarray
3380-shortest-subarray-with-or-at-least-k-ii
3429-special-array-i
3518-maximum-multiplication-score
3522-find-the-power-of-k-size-subarrays-i
3558-find-a-safe-walk-through-a-grid
3579-maximum-possible-number-by-binary-concatenation
3582-find-indices-of-stable-mountains

Hash Table

0001-two-sum
0003-longest-substring-without-repeating-characters
0013-roman-to-integer
0017-letter-combinations-of-a-phone-number
0037-sudoku-solver
0073-set-matrix-zeroes
0076-minimum-window-substring
0105-construct-binary-tree-from-preorder-and-inorder-traversal
0106-construct-binary-tree-from-inorder-and-postorder-traversal
0127-word-ladder
0128-longest-consecutive-sequence
0139-word-break
0141-linked-list-cycle
0142-linked-list-cycle-ii
0146-lru-cache
0160-intersection-of-two-linked-lists
0169-majority-element
0229-majority-element-ii
0242-valid-anagram
0264-ugly-number-ii
0268-missing-number
0347-top-k-frequent-elements
0424-longest-repeating-character-replacement
0432-all-oone-data-structure
0451-sort-characters-by-frequency
0560-subarray-sum-equals-k
0567-permutation-in-string
0621-task-scheduler
0632-smallest-range-covering-elements-from-k-lists
0653-two-sum-iv-input-is-a-bst
0870-magic-squares-in-grid
0876-hand-of-straights
0893-all-nodes-distance-k-in-binary-tree
0906-walking-robot-simulation
0920-uncommon-words-from-two-sentences
0966-binary-subarrays-with-sum
0984-most-stones-removed-with-same-row-or-column
0999-regions-cut-by-slashes
1029-vertical-order-traversal-of-a-binary-tree
1034-subarrays-with-k-different-integers
1207-delete-nodes-and-return-forest
1227-number-of-equivalent-domino-pairs
1256-rank-transform-of-an-array
1370-count-number-of-nice-subarrays
1460-number-of-substrings-containing-all-three-characters
1468-check-if-n-and-its-double-exist
1473-find-the-longest-substring-containing-vowels-in-even-counts
1556-make-two-arrays-equal-by-reversing-subarrays
1620-check-if-array-pairs-are-divisible-by-k
1694-make-sum-divisible-by-p
1715-split-a-string-into-the-max-number-of-unique-substrings
1741-sort-array-by-increasing-frequency
1786-count-the-number-of-consistent-strings
1890-sum-of-beauty-of-all-substrings
1915-check-if-one-string-swap-can-make-strings-equal
2054-the-number-of-the-smallest-unoccupied-chair
2163-kth-distinct-string-in-an-array
2356-largest-combination-with-bitwise-and-greater-than-zero
2502-sort-the-people
2581-divide-players-into-teams-of-equal-skill
2586-longest-square-streak-in-an-array
2677-cousins-in-binary-tree-ii
2685-first-completely-painted-row-or-column
2755-extra-characters-in-a-string
2766-find-the-prefix-common-array-of-two-arrays
3276-minimum-number-of-pushes-to-type-word-ii
3329-find-the-length-of-the-longest-common-prefix

Tree

0094-binary-tree-inorder-traversal
0098-validate-binary-search-tree
0100-same-tree
0101-symmetric-tree
0102-binary-tree-level-order-traversal
0103-binary-tree-zigzag-level-order-traversal
0104-maximum-depth-of-binary-tree
0105-construct-binary-tree-from-preorder-and-inorder-traversal
0106-construct-binary-tree-from-inorder-and-postorder-traversal
0110-balanced-binary-tree
0114-flatten-binary-tree-to-linked-list
0124-binary-tree-maximum-path-sum
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0199-binary-tree-right-side-view
0222-count-complete-tree-nodes
0230-kth-smallest-element-in-a-bst
0235-lowest-common-ancestor-of-a-binary-search-tree
0236-lowest-common-ancestor-of-a-binary-tree
0297-serialize-and-deserialize-binary-tree
0450-delete-node-in-a-bst
0543-diameter-of-binary-tree
0653-two-sum-iv-input-is-a-bst
0662-maximum-width-of-binary-tree
0776-n-ary-tree-postorder-traversal
0783-search-in-a-binary-search-tree
0784-insert-into-a-binary-search-tree
0789-kth-largest-element-in-a-stream
0893-all-nodes-distance-k-in-binary-tree
1029-vertical-order-traversal-of-a-binary-tree
1050-construct-binary-search-tree-from-preorder-traversal
1207-delete-nodes-and-return-forest
1484-linked-list-in-binary-tree
1653-number-of-good-leaf-nodes-pairs
2384-root-equals-sum-of-children
2545-height-of-binary-tree-after-subtree-removal-queries
2646-kth-largest-sum-in-a-binary-tree
2677-cousins-in-binary-tree-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
0114-flatten-binary-tree-to-linked-list
0124-binary-tree-maximum-path-sum
0130-surrounded-regions
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0199-binary-tree-right-side-view
0207-course-schedule
0210-course-schedule-ii
0230-kth-smallest-element-in-a-bst
0235-lowest-common-ancestor-of-a-binary-search-tree
0236-lowest-common-ancestor-of-a-binary-tree
0297-serialize-and-deserialize-binary-tree
0386-lexicographical-numbers
0543-diameter-of-binary-tree
0547-number-of-provinces
0653-two-sum-iv-input-is-a-bst
0662-maximum-width-of-binary-tree
0733-flood-fill
0744-network-delay-time
0776-n-ary-tree-postorder-traversal
0801-is-graph-bipartite
0803-cheapest-flights-within-k-stops
0820-find-eventual-safe-states
0893-all-nodes-distance-k-in-binary-tree
0984-most-stones-removed-with-same-row-or-column
0999-regions-cut-by-slashes
1029-vertical-order-traversal-of-a-binary-tree
1073-number-of-enclaves
1207-delete-nodes-and-return-forest
1350-remove-sub-folders-from-the-filesystem
1484-linked-list-in-binary-tree
1653-number-of-good-leaf-nodes-pairs
1691-minimum-number-of-days-to-disconnect-island
1753-path-with-minimum-effort
2035-count-sub-islands
2545-height-of-binary-tree-after-subtree-removal-queries
2677-cousins-in-binary-tree-ii

Binary Tree

0094-binary-tree-inorder-traversal
0098-validate-binary-search-tree
0100-same-tree
0101-symmetric-tree
0102-binary-tree-level-order-traversal
0103-binary-tree-zigzag-level-order-traversal
0104-maximum-depth-of-binary-tree
0105-construct-binary-tree-from-preorder-and-inorder-traversal
0106-construct-binary-tree-from-inorder-and-postorder-traversal
0110-balanced-binary-tree
0114-flatten-binary-tree-to-linked-list
0124-binary-tree-maximum-path-sum
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0199-binary-tree-right-side-view
0222-count-complete-tree-nodes
0230-kth-smallest-element-in-a-bst
0235-lowest-common-ancestor-of-a-binary-search-tree
0236-lowest-common-ancestor-of-a-binary-tree
0297-serialize-and-deserialize-binary-tree
0450-delete-node-in-a-bst
0543-diameter-of-binary-tree
0653-two-sum-iv-input-is-a-bst
0662-maximum-width-of-binary-tree
0783-search-in-a-binary-search-tree
0784-insert-into-a-binary-search-tree
0789-kth-largest-element-in-a-stream
0893-all-nodes-distance-k-in-binary-tree
1029-vertical-order-traversal-of-a-binary-tree
1050-construct-binary-search-tree-from-preorder-traversal
1207-delete-nodes-and-return-forest
1484-linked-list-in-binary-tree
1653-number-of-good-leaf-nodes-pairs
2384-root-equals-sum-of-children
2545-height-of-binary-tree-after-subtree-removal-queries
2646-kth-largest-sum-in-a-binary-tree
2677-cousins-in-binary-tree-ii

Greedy

0044-wildcard-matching
0055-jump-game
0135-candy
0179-largest-number
0402-remove-k-digits
0410-split-array-largest-sum
0435-non-overlapping-intervals
0455-assign-cookies
0621-task-scheduler
0624-maximum-distance-in-arrays
0632-smallest-range-covering-elements-from-k-lists
0670-maximum-swap
0876-hand-of-straights
0890-lemonade-change
0957-minimum-add-to-make-parentheses-valid
1304-longest-happy-string
1711-find-valid-matrix-given-row-and-column-sums
1766-minimum-number-of-removals-to-make-mountain-array
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
2716-prime-subtraction-operation
3171-minimum-equal-sum-of-two-arrays-after-replacing-zeros
3195-separate-black-and-white-balls
3276-minimum-number-of-pushes-to-type-word-ii

Recursion

0002-add-two-numbers
0044-wildcard-matching
0050-powx-n
0206-reverse-linked-list
0231-power-of-two
0234-palindrome-linked-list
0241-different-ways-to-add-parentheses
0273-integer-to-english-words
1197-parsing-a-boolean-expression
1667-find-kth-bit-in-nth-binary-string
2050-count-good-numbers

Sorting

0015-3sum
0018-4sum
0056-merge-intervals
0075-sort-colors
0088-merge-sorted-array
0148-sort-list
0169-majority-element
0179-largest-number
0215-kth-largest-element-in-an-array
0229-majority-element-ii
0242-valid-anagram
0268-missing-number
0295-find-median-from-data-stream
0347-top-k-frequent-elements
0435-non-overlapping-intervals
0451-sort-characters-by-frequency
0455-assign-cookies
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
0948-sort-an-array
1029-vertical-order-traversal-of-a-binary-tree
1256-rank-transform-of-an-array
1333-sort-the-jumbled-numbers
1468-check-if-n-and-its-double-exist
1556-make-two-arrays-equal-by-reversing-subarrays
1615-range-sum-of-sorted-subarray-sums
1741-sort-array-by-increasing-frequency
2179-most-beautiful-item-for-each-query
2488-divide-intervals-into-minimum-number-of-groups
2502-sort-the-people
2581-divide-players-into-teams-of-equal-skill
2586-longest-square-streak-in-an-array
2646-kth-largest-sum-in-a-binary-tree
2699-count-the-number-of-fair-pairs
3276-minimum-number-of-pushes-to-type-word-ii
3291-find-if-array-can-be-sorted

Heap (Priority Queue)

0023-merge-k-sorted-lists
0215-kth-largest-element-in-an-array
0264-ugly-number-ii
0295-find-median-from-data-stream
0347-top-k-frequent-elements
0373-find-k-pairs-with-smallest-sums
0451-sort-characters-by-frequency
0621-task-scheduler
0632-smallest-range-covering-elements-from-k-lists
0744-network-delay-time
0789-kth-largest-element-in-a-stream
0803-cheapest-flights-within-k-stops
0892-shortest-subarray-with-sum-at-least-k
0948-sort-an-array
1304-longest-happy-string
1325-path-with-maximum-probability
1753-path-with-minimum-effort
2054-the-number-of-the-smallest-unoccupied-chair
2488-divide-intervals-into-minimum-number-of-groups
2616-maximal-score-after-applying-k-operations
2803-modify-graph-edge-weights
3558-find-a-safe-walk-through-a-grid

Bucket Sort

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

Counting

0169-majority-element
0229-majority-element-ii
0347-top-k-frequent-elements
0451-sort-characters-by-frequency
0621-task-scheduler
0920-uncommon-words-from-two-sentences
1034-subarrays-with-k-different-integers
1227-number-of-equivalent-domino-pairs
1620-check-if-array-pairs-are-divisible-by-k
1786-count-the-number-of-consistent-strings
1890-sum-of-beauty-of-all-substrings
1915-check-if-one-string-swap-can-make-strings-equal
2163-kth-distinct-string-in-an-array
2356-largest-combination-with-bitwise-and-greater-than-zero
2494-sum-of-prefix-scores-of-strings
3276-minimum-number-of-pushes-to-type-word-ii

Stack

0084-largest-rectangle-in-histogram
0094-binary-tree-inorder-traversal
0114-flatten-binary-tree-to-linked-list
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0234-palindrome-linked-list
0402-remove-k-digits
0735-asteroid-collision
0776-n-ary-tree-postorder-traversal
0937-online-stock-span
0943-sum-of-subarray-minimums
0957-minimum-add-to-make-parentheses-valid
1002-maximum-width-ramp
1050-construct-binary-search-tree-from-preorder-traversal
1197-parsing-a-boolean-expression
1497-design-a-stack-with-increment-operation
1679-shortest-subarray-to-be-removed-to-make-array-sorted
1737-maximum-nesting-depth-of-the-parentheses
1756-minimum-deletions-to-make-string-balanced
2095-minimum-number-of-swaps-to-make-the-string-balanced
2227-sum-of-subarray-ranges
2800-minimum-string-length-after-removing-substrings

Math

0002-add-two-numbers
0013-roman-to-integer
0048-rotate-image
0050-powx-n
0189-rotate-array
0231-power-of-two
0241-different-ways-to-add-parentheses
0264-ugly-number-ii
0268-missing-number
0273-integer-to-english-words
0282-expression-add-operators
0539-minimum-time-difference
0564-find-the-closest-palindrome
0592-fraction-addition-and-subtraction
0650-2-keys-keyboard
0670-maximum-swap
0870-magic-squares-in-grid
1240-stone-game-ii
1370-count-number-of-nice-subarrays
1421-find-numbers-with-even-number-of-digits
2050-count-good-numbers
2155-find-missing-observations
2716-prime-subtraction-operation
2903-insert-greatest-common-divisors-in-linked-list
3567-convert-date-to-binary

Two Pointers

0015-3sum
0018-4sum
0019-remove-nth-node-from-end-of-list
0026-remove-duplicates-from-sorted-array
0031-next-permutation
0075-sort-colors
0088-merge-sorted-array
0141-linked-list-cycle
0142-linked-list-cycle-ii
0148-sort-list
0151-reverse-words-in-a-string
0160-intersection-of-two-linked-lists
0189-rotate-array
0234-palindrome-linked-list
0283-move-zeroes
0295-find-median-from-data-stream
0455-assign-cookies
0567-permutation-in-string
0653-two-sum-iv-input-is-a-bst
0719-find-k-th-smallest-pair-distance
0908-middle-of-the-linked-list
1468-check-if-n-and-its-double-exist
1615-range-sum-of-sorted-subarray-sums
1679-shortest-subarray-to-be-removed-to-make-array-sorted
1923-sentence-similarity-iii
2095-minimum-number-of-swaps-to-make-the-string-balanced
2216-delete-the-middle-node-of-a-linked-list
2271-rearrange-array-elements-by-sign
2488-divide-intervals-into-minimum-number-of-groups
2581-divide-players-into-teams-of-equal-skill
2699-count-the-number-of-fair-pairs
3195-separate-black-and-white-balls

String Matching

0214-shortest-palindrome
0812-rotate-string

Matrix

0037-sudoku-solver
0048-rotate-image
0054-spiral-matrix
0073-set-matrix-zeroes
0079-word-search
0130-surrounded-regions
0542-01-matrix
0733-flood-fill
0870-magic-squares-in-grid
0921-spiral-matrix-iii
0999-regions-cut-by-slashes
1036-rotting-oranges
1073-number-of-enclaves
1171-shortest-path-in-binary-matrix
1402-count-square-submatrices-with-all-ones
1496-lucky-numbers-in-a-matrix
1691-minimum-number-of-days-to-disconnect-island
1711-find-valid-matrix-given-row-and-column-sums
1753-path-with-minimum-effort
1876-map-of-highest-peak
2035-count-sub-islands
2132-convert-1d-array-into-2d-array
2145-grid-game
2411-spiral-matrix-iv
2472-build-a-matrix-with-conditions
2685-first-completely-painted-row-or-column
2794-maximum-number-of-moves-in-a-grid
3558-find-a-safe-walk-through-a-grid

Binary Search

0033-search-in-rotated-sorted-array
0034-find-first-and-last-position-of-element-in-sorted-array
0035-search-insert-position
0081-search-in-rotated-sorted-array-ii
0153-find-minimum-in-rotated-sorted-array
0162-find-peak-element
0222-count-complete-tree-nodes
0268-missing-number
0410-split-array-largest-sum
0493-reverse-pairs
0540-single-element-in-a-sorted-array
0719-find-k-th-smallest-pair-distance
0729-my-calendar-i
0731-my-calendar-ii
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
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
1615-range-sum-of-sorted-subarray-sums
1646-kth-missing-positive-number
1679-shortest-subarray-to-be-removed-to-make-array-sorted
1753-path-with-minimum-effort
1766-minimum-number-of-removals-to-make-mountain-array
2006-find-the-student-that-will-replace-the-chalk
2179-most-beautiful-item-for-each-query
2188-minimized-maximum-of-products-distributed-to-any-store
2586-longest-square-streak-in-an-array
2699-count-the-number-of-fair-pairs
2716-prime-subtraction-operation

Bit Manipulation

0078-subsets
0090-subsets-ii
0222-count-complete-tree-nodes
0231-power-of-two
0268-missing-number
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
2170-count-number-of-maximum-bitwise-or-subsets
2323-minimum-bit-flips-to-convert-number
2356-largest-combination-with-bitwise-and-greater-than-zero
2503-longest-subarray-with-maximum-bitwise-and
2533-bitwise-xor-of-all-pairings
2766-find-the-prefix-common-array-of-two-arrays
2792-neighboring-bitwise-xor
3291-find-if-array-can-be-sorted
3380-shortest-subarray-with-or-at-least-k-ii
3394-minimum-array-end
3579-maximum-possible-number-by-binary-concatenation

Graph

0207-course-schedule
0210-course-schedule-ii
0547-number-of-provinces
0744-network-delay-time
0801-is-graph-bipartite
0803-cheapest-flights-within-k-stops
0820-find-eventual-safe-states
0984-most-stones-removed-with-same-row-or-column
1325-path-with-maximum-probability
1456-find-the-city-with-the-smallest-number-of-neighbors-at-a-threshold-distance
2090-number-of-ways-to-arrive-at-destination
2171-second-minimum-time-to-reach-destination
2472-build-a-matrix-with-conditions
2803-modify-graph-edge-weights
3235-minimum-cost-to-convert-string-i
3558-find-a-safe-walk-through-a-grid

Topological Sort

0207-course-schedule
0210-course-schedule-ii
0820-find-eventual-safe-states
2090-number-of-ways-to-arrive-at-destination
2472-build-a-matrix-with-conditions

Divide and Conquer

0023-merge-k-sorted-lists
0053-maximum-subarray
0105-construct-binary-tree-from-preorder-and-inorder-traversal
0106-construct-binary-tree-from-inorder-and-postorder-traversal
0148-sort-list
0169-majority-element
0215-kth-largest-element-in-an-array
0347-top-k-frequent-elements
0493-reverse-pairs
0948-sort-an-array

Simulation

0054-spiral-matrix
0592-fraction-addition-and-subtraction
0735-asteroid-collision
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
2271-rearrange-array-elements-by-sign
2411-spiral-matrix-iv
2800-minimum-string-length-after-removing-substrings

Union Find

0128-longest-consecutive-sequence
0130-surrounded-regions
0547-number-of-provinces
0801-is-graph-bipartite
0984-most-stones-removed-with-same-row-or-column
0999-regions-cut-by-slashes
1073-number-of-enclaves
1753-path-with-minimum-effort
2035-count-sub-islands

Prefix Sum

0410-split-array-largest-sum
0560-subarray-sum-equals-k
0731-my-calendar-ii
0892-shortest-subarray-with-sum-at-least-k
0966-binary-subarrays-with-sum
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
1538-maximum-points-you-can-obtain-from-cards
1694-make-sum-divisible-by-p
2006-find-the-student-that-will-replace-the-chalk
2145-grid-game
2488-divide-intervals-into-minimum-number-of-groups

Merge Sort

0023-merge-k-sorted-lists
0148-sort-list
0493-reverse-pairs
0948-sort-an-array

Radix Sort

0948-sort-an-array

Counting Sort

0948-sort-an-array

Shortest Path

0744-network-delay-time
0803-cheapest-flights-within-k-stops
1325-path-with-maximum-probability
1456-find-the-city-with-the-smallest-number-of-neighbors-at-a-threshold-distance
2090-number-of-ways-to-arrive-at-destination
2171-second-minimum-time-to-reach-destination
2803-modify-graph-edge-weights
3235-minimum-cost-to-convert-string-i
3558-find-a-safe-walk-through-a-grid

Breadth-First Search

0100-same-tree
0101-symmetric-tree
0102-binary-tree-level-order-traversal
0103-binary-tree-zigzag-level-order-traversal
0104-maximum-depth-of-binary-tree
0127-word-ladder
0130-surrounded-regions
0199-binary-tree-right-side-view
0207-course-schedule
0210-course-schedule-ii
0297-serialize-and-deserialize-binary-tree
0542-01-matrix
0547-number-of-provinces
0653-two-sum-iv-input-is-a-bst
0662-maximum-width-of-binary-tree
0733-flood-fill
0744-network-delay-time
0801-is-graph-bipartite
0803-cheapest-flights-within-k-stops
0820-find-eventual-safe-states
0893-all-nodes-distance-k-in-binary-tree
0999-regions-cut-by-slashes
1029-vertical-order-traversal-of-a-binary-tree
1036-rotting-oranges
1073-number-of-enclaves
1171-shortest-path-in-binary-matrix
1484-linked-list-in-binary-tree
1691-minimum-number-of-days-to-disconnect-island
1753-path-with-minimum-effort
1876-map-of-highest-peak
2035-count-sub-islands
2171-second-minimum-time-to-reach-destination
2545-height-of-binary-tree-after-subtree-removal-queries
2646-kth-largest-sum-in-a-binary-tree
2677-cousins-in-binary-tree-ii
3558-find-a-safe-walk-through-a-grid

Binary Indexed Tree

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

Segment Tree

0493-reverse-pairs
0729-my-calendar-i
0731-my-calendar-ii

Ordered Set

0493-reverse-pairs
0729-my-calendar-i
0731-my-calendar-ii

Backtracking

0017-letter-combinations-of-a-phone-number
0022-generate-parentheses
0037-sudoku-solver
0039-combination-sum
0040-combination-sum-ii
0051-n-queens
0078-subsets
0079-word-search
0090-subsets-ii
0131-palindrome-partitioning
0216-combination-sum-iii
0282-expression-add-operators
1715-split-a-string-into-the-max-number-of-unique-substrings
2170-count-number-of-maximum-bitwise-or-subsets

Sliding Window

0003-longest-substring-without-repeating-characters
0076-minimum-window-substring
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
0966-binary-subarrays-with-sum
1034-subarrays-with-k-different-integers
1046-max-consecutive-ones-iii
1370-count-number-of-nice-subarrays
1460-number-of-substrings-containing-all-three-characters
1538-maximum-points-you-can-obtain-from-cards
1755-defuse-the-bomb
2255-minimum-swaps-to-group-all-1s-together-ii
3380-shortest-subarray-with-or-at-least-k-ii
3522-find-the-power-of-k-size-subarrays-i

Trie

0139-word-break
0386-lexicographical-numbers
0440-k-th-smallest-in-lexicographical-order
1350-remove-sub-folders-from-the-filesystem
2494-sum-of-prefix-scores-of-strings
2755-extra-characters-in-a-string
3329-find-the-length-of-the-longest-common-prefix

Memoization

0139-word-break
0241-different-ways-to-add-parentheses

Strongly Connected Component

1691-minimum-number-of-days-to-disconnect-island

Design

0146-lru-cache
0295-find-median-from-data-stream
0297-serialize-and-deserialize-binary-tree
0432-all-oone-data-structure
0729-my-calendar-i
0731-my-calendar-ii
0789-kth-largest-element-in-a-stream
0859-design-circular-deque
0937-online-stock-span
1497-design-a-stack-with-increment-operation

Binary Search Tree

0098-validate-binary-search-tree
0230-kth-smallest-element-in-a-bst
0235-lowest-common-ancestor-of-a-binary-search-tree
0450-delete-node-in-a-bst
0653-two-sum-iv-input-is-a-bst
0783-search-in-a-binary-search-tree
0784-insert-into-a-binary-search-tree
0789-kth-largest-element-in-a-stream
1050-construct-binary-search-tree-from-preorder-traversal

Data Stream

0295-find-median-from-data-stream
0789-kth-largest-element-in-a-stream
0937-online-stock-span

Quickselect

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

Linked List

0002-add-two-numbers
0019-remove-nth-node-from-end-of-list
0023-merge-k-sorted-lists
0114-flatten-binary-tree-to-linked-list
0141-linked-list-cycle
0142-linked-list-cycle-ii
0146-lru-cache
0148-sort-list
0160-intersection-of-two-linked-lists
0206-reverse-linked-list
0234-palindrome-linked-list
0237-delete-node-in-a-linked-list
0328-odd-even-linked-list
0432-all-oone-data-structure
0725-split-linked-list-in-parts
0859-design-circular-deque
0908-middle-of-the-linked-list
1484-linked-list-in-binary-tree
2216-delete-the-middle-node-of-a-linked-list
2411-spiral-matrix-iv
2903-insert-greatest-common-divisors-in-linked-list

Game Theory

1240-stone-game-ii

Monotonic Stack

0084-largest-rectangle-in-histogram
0402-remove-k-digits
0937-online-stock-span
0943-sum-of-subarray-minimums
1002-maximum-width-ramp
1050-construct-binary-search-tree-from-preorder-traversal
1679-shortest-subarray-to-be-removed-to-make-array-sorted
2227-sum-of-subarray-ranges

Doubly-Linked List

0146-lru-cache
0432-all-oone-data-structure

Number Theory

2716-prime-subtraction-operation
2903-insert-greatest-common-divisors-in-linked-list

Brainteaser

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

Rolling Hash

0214-shortest-palindrome

Hash Function

0214-shortest-palindrome

Queue

0859-design-circular-deque
0892-shortest-subarray-with-sum-at-least-k

Enumeration

2170-count-number-of-maximum-bitwise-or-subsets
3579-maximum-possible-number-by-binary-concatenation

Monotonic Queue

0892-shortest-subarray-with-sum-at-least-k