LeetCode_code

LeetCode Topics

String

0038-count-and-say
0768-partition-labels
0868-push-dominoes
1058-lexicographically-smallest-equivalent-string
1093-recover-a-tree-from-preorder-traversal
1160-letter-tile-possibilities
1170-shortest-common-supersequence
1302-delete-characters-to-make-fancy-string
1350-remove-sub-folders-from-the-filesystem
1460-number-of-substrings-containing-all-three-characters
1516-the-k-th-lexicographical-string-of-all-happy-strings-of-length-n
1818-maximum-score-from-removing-substrings
1915-check-if-one-string-swap-can-make-strings-equal
2021-remove-all-occurrences-of-a-substring
2079-delete-duplicate-folders-in-system
2140-longest-subsequence-repeated-k-times
2220-find-all-possible-recipes-from-given-supplies
2221-check-if-a-parentheses-string-can-be-valid
2237-longest-palindrome-by-concatenating-two-letter-words
2260-divide-a-string-into-groups-of-size-k
2346-largest-3-same-digit-number-in-string
2395-longest-binary-subsequence-less-than-or-equal-to-k
2456-construct-smallest-number-from-di-string
2463-minimum-recolors-to-get-k-consecutive-black-blocks
3142-longest-unequal-adjacent-groups-subsequence-ii
3143-longest-unequal-adjacent-groups-subsequence-i
3243-count-the-number-of-powerful-integers
3360-minimum-deletions-to-make-string-k-special
3447-clear-digits
3455-minimum-length-of-string-after-operations
3569-count-of-substrings-containing-every-vowel-and-k-consonants-ii
3617-find-the-original-typed-string-i
3618-find-the-original-typed-string-ii
3629-total-characters-in-string-after-transformations-i
3637-count-number-of-balanced-permutations
3683-find-the-lexicographically-largest-string-from-the-box-i
3761-maximum-difference-between-even-and-odd-frequency-ii

Stack

1628-count-submatrices-with-all-ones
1818-maximum-score-from-removing-substrings
2021-remove-all-occurrences-of-a-substring
2221-check-if-a-parentheses-string-can-be-valid
2456-construct-smallest-number-from-di-string
3447-clear-digits

Greedy

0135-candy
0768-partition-labels
1049-minimum-domino-rotations-for-equal-row
1448-maximum-69-number
1478-maximum-number-of-events-that-can-be-attended
1818-maximum-score-from-removing-substrings
2140-longest-subsequence-repeated-k-times
2180-maximum-number-of-tasks-you-can-assign
2221-check-if-a-parentheses-string-can-be-valid
2237-longest-palindrome-by-concatenating-two-letter-words
2387-partition-array-such-that-maximum-difference-is-k
2395-longest-binary-subsequence-less-than-or-equal-to-k
2456-construct-smallest-number-from-di-string
2509-minimize-xor
2681-put-marbles-in-bags
2689-rearranging-fruits
2704-maximum-difference-by-remapping-a-digit
3143-longest-unequal-adjacent-groups-subsequence-i
3171-minimum-equal-sum-of-two-arrays-after-replacing-zeros
3307-find-the-maximum-sum-of-node-values
3360-minimum-deletions-to-make-string-k-special
3741-reschedule-meetings-for-maximum-free-time-ii
3743-reschedule-meetings-for-maximum-free-time-i
3788-maximum-unique-subarray-sum-after-deletion

Array

0066-plus-one
0073-set-matrix-zeroes
0075-sort-colors
0118-pascals-triangle
0135-candy
0368-largest-divisible-subset
0407-trapping-rain-water-ii
0416-partition-equal-subset-sum
0498-diagonal-traverse
0679-24-game
0854-making-a-large-island
0905-length-of-longest-fibonacci-subsequence
0934-bitwise-ors-of-subarrays
0945-snakes-and-ladders
1049-minimum-domino-rotations-for-equal-row
1227-number-of-equivalent-domino-pairs
1293-three-consecutive-odds
1335-maximum-candies-allocated-to-k-children
1350-remove-sub-folders-from-the-filesystem
1364-tuple-with-same-product
1396-count-servers-that-communicate
1402-count-square-submatrices-with-all-ones
1421-find-numbers-with-even-number-of-digits
1424-maximum-candies-you-can-get-from-boxes
1477-product-of-the-last-k-numbers
1478-maximum-number-of-events-that-can-be-attended
1485-minimum-cost-to-make-at-least-one-valid-path-in-a-grid
1510-find-lucky-integer-in-an-array
1628-count-submatrices-with-all-ones
1656-count-good-triplets
1813-maximum-erasure-value
1819-construct-the-lexicographically-largest-valid-sequence
1849-maximum-absolute-sum-of-any-subarray
1851-maximum-number-of-events-that-can-be-attended-ii
1876-map-of-highest-peak
1878-check-if-array-is-sorted-and-rotated
1927-maximum-ascending-subarray-sum
1995-finding-pairs-with-a-certain-sum
2048-build-array-from-permutation
2079-delete-duplicate-folders-in-system
2144-maximum-difference-between-increasing-elements
2145-grid-game
2150-kth-smallest-product-of-two-sorted-arrays
2160-minimum-operations-to-make-a-uni-value-grid
2180-maximum-number-of-tasks-you-can-assign
2204-find-subsequence-of-length-k-with-the-largest-sum
2220-find-all-possible-recipes-from-given-supplies
2229-maximum-fruits-harvested-after-at-most-k-steps
2237-longest-palindrome-by-concatenating-two-letter-words
2249-count-the-hidden-sequences
2265-partition-array-according-to-given-pivot
2267-minimum-difference-in-sums-after-removal-of-elements
2277-count-equal-and-divisible-pairs-in-an-array
2280-count-good-triplets-in-an-array
2308-divide-array-into-equal-pairs
2387-partition-array-such-that-maximum-difference-is-k
2394-count-subarrays-with-score-less-than-k
2400-minimum-score-after-removals-on-a-tree
2432-number-of-zero-filled-subarrays
2448-count-number-of-bad-pairs
2473-max-sum-of-a-pair-with-equal-sum-of-digits
2478-longest-nice-subarray
2479-meeting-rooms-iii
2498-smallest-subarrays-with-maximum-bitwise-or
2527-count-subarrays-with-fixed-bounds
2529-range-product-queries-of-powers
2533-bitwise-xor-of-all-pairings
2551-apply-operations-to-an-array
2564-most-profitable-path-in-a-tree
2665-minimum-time-to-repair-cars
2681-put-marbles-in-bags
2685-first-completely-painted-row-or-column
2689-rearranging-fruits
2690-house-robber-iv
2699-count-the-number-of-fair-pairs
2707-merge-two-2d-arrays-by-summing-values
2766-find-the-prefix-common-array-of-two-arrays
2792-neighboring-bitwise-xor
2856-count-complete-subarrays-in-an-array
2915-count-of-interesting-subarrays
3142-longest-unequal-adjacent-groups-subsequence-ii
3143-longest-unequal-adjacent-groups-subsequence-i
3152-maximum-value-of-an-ordered-triplet-ii
3154-maximum-value-of-an-ordered-triplet-i
3171-minimum-equal-sum-of-two-arrays-after-replacing-zeros
3219-make-lexicographically-smallest-array-by-swapping-elements
3227-find-missing-and-repeated-values
3251-maximum-area-of-longest-diagonal-rectangle
3307-find-the-maximum-sum-of-node-values
3321-type-of-triangle
3332-minimum-operations-to-exceed-threshold-value-ii
3348-minimum-cost-walk-in-weighted-graph
3372-longest-strictly-increasing-or-strictly-decreasing-subarray
3430-count-days-without-meetings
3459-find-the-minimum-area-to-cover-all-ones-ii
3483-alternating-groups-ii
3491-find-the-maximum-length-of-valid-subsequence-ii
3621-minimum-operations-to-make-array-values-equal-to-k
3627-find-minimum-time-to-reach-last-room-i
3628-find-minimum-time-to-reach-last-room-ii
3639-zero-array-transformation-i
3643-zero-array-transformation-ii
3657-check-if-grid-can-be-cut-into-sections
3685-count-subarrays-of-length-three-with-a-condition
3733-length-of-longest-v-shaped-diagonal-segment
3741-reschedule-meetings-for-maximum-free-time-ii
3743-reschedule-meetings-for-maximum-free-time-i
3747-maximum-difference-between-adjacent-elements-in-a-circular-array
3788-maximum-unique-subarray-sum-after-deletion
3789-maximize-subarrays-after-removing-one-conflicting-pair
3791-fruits-into-baskets-iii

Math

0066-plus-one
0342-power-of-four
0368-largest-divisible-subset
0679-24-game
0826-soup-servings
0900-reordered-power-of-2
1421-find-numbers-with-even-number-of-digits
1448-maximum-69-number
1477-product-of-the-last-k-numbers
1500-count-largest-group
1889-check-if-number-is-a-sum-of-powers-of-three
2050-count-good-numbers
2160-minimum-operations-to-make-a-uni-value-grid
2202-sum-of-k-mirror-numbers
2415-count-the-number-of-ideal-arrays
2432-number-of-zero-filled-subarrays
2448-count-number-of-bad-pairs
2610-closest-prime-numbers-in-range
2649-count-total-number-of-colored-cells
2704-maximum-difference-by-remapping-a-digit
2802-find-the-punishment-number-of-an-integer
2998-count-symmetric-integers
3172-divisible-and-non-divisible-sums-difference
3227-find-missing-and-repeated-values
3243-count-the-number-of-powerful-integers
3321-type-of-triangle
3548-find-the-count-of-good-integers
3600-find-the-k-th-character-in-string-game-i
3629-total-characters-in-string-after-transformations-i
3637-count-number-of-balanced-permutations
3682-count-the-number-of-arrays-with-k-matching-adjacent-elements

Hash Table

0073-set-matrix-zeroes
0768-partition-labels
0900-reordered-power-of-2
0905-length-of-longest-fibonacci-subsequence
1160-letter-tile-possibilities
1227-number-of-equivalent-domino-pairs
1364-tuple-with-same-product
1460-number-of-substrings-containing-all-three-characters
1500-count-largest-group
1510-find-lucky-integer-in-an-array
1813-maximum-erasure-value
1915-check-if-one-string-swap-can-make-strings-equal
1986-largest-color-value-in-a-directed-graph
1995-finding-pairs-with-a-certain-sum
2079-delete-duplicate-folders-in-system
2204-find-subsequence-of-length-k-with-the-largest-sum
2220-find-all-possible-recipes-from-given-supplies
2237-longest-palindrome-by-concatenating-two-letter-words
2308-divide-array-into-equal-pairs
2434-design-a-number-container-system
2448-count-number-of-bad-pairs
2473-max-sum-of-a-pair-with-equal-sum-of-digits
2479-meeting-rooms-iii
2685-first-completely-painted-row-or-column
2689-rearranging-fruits
2707-merge-two-2d-arrays-by-summing-values
2766-find-the-prefix-common-array-of-two-arrays
2856-count-complete-subarrays-in-an-array
2915-count-of-interesting-subarrays
3227-find-missing-and-repeated-values
3360-minimum-deletions-to-make-string-k-special
3455-minimum-length-of-string-after-operations
3548-find-the-count-of-good-integers
3569-count-of-substrings-containing-every-vowel-and-k-consonants-ii
3621-minimum-operations-to-make-array-values-equal-to-k
3629-total-characters-in-string-after-transformations-i
3788-maximum-unique-subarray-sum-after-deletion

Counting

0900-reordered-power-of-2
1160-letter-tile-possibilities
1227-number-of-equivalent-domino-pairs
1364-tuple-with-same-product
1396-count-servers-that-communicate
1510-find-lucky-integer-in-an-array
1915-check-if-one-string-swap-can-make-strings-equal
1986-largest-color-value-in-a-directed-graph
2140-longest-subsequence-repeated-k-times
2237-longest-palindrome-by-concatenating-two-letter-words
2308-divide-array-into-equal-pairs
2448-count-number-of-bad-pairs
3360-minimum-deletions-to-make-string-k-special
3455-minimum-length-of-string-after-operations
3629-total-characters-in-string-after-transformations-i

Bit Manipulation

0342-power-of-four
0934-bitwise-ors-of-subarrays
2308-divide-array-into-equal-pairs
2400-minimum-score-after-removals-on-a-tree
2478-longest-nice-subarray
2498-smallest-subarrays-with-maximum-bitwise-or
2509-minimize-xor
2529-range-product-queries-of-powers
2533-bitwise-xor-of-all-pairings
2766-find-the-prefix-common-array-of-two-arrays
2792-neighboring-bitwise-xor
3307-find-the-maximum-sum-of-node-values
3348-minimum-cost-walk-in-weighted-graph
3600-find-the-k-th-character-in-string-game-i

Brainteaser

2533-bitwise-xor-of-all-pairings

Breadth-First Search

0407-trapping-rain-water-ii
0684-redundant-connection
0820-find-eventual-safe-states
0854-making-a-large-island
0945-snakes-and-ladders
1396-count-servers-that-communicate
1424-maximum-candies-you-can-get-from-boxes
1485-minimum-cost-to-make-at-least-one-valid-path-in-a-grid
1558-course-schedule-iv
1876-map-of-highest-peak
2564-most-profitable-path-in-a-tree
2583-divide-nodes-into-the-maximum-number-of-groups
3633-maximize-the-number-of-target-nodes-after-connecting-trees-i
3645-maximize-the-number-of-target-nodes-after-connecting-trees-ii

Graph

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

Heap (Priority Queue)

0407-trapping-rain-water-ii
1478-maximum-number-of-events-that-can-be-attended
1485-minimum-cost-to-make-at-least-one-valid-path-in-a-grid
2204-find-subsequence-of-length-k-with-the-largest-sum
2267-minimum-difference-in-sums-after-removal-of-elements
2434-design-a-number-container-system
2473-max-sum-of-a-pair-with-equal-sum-of-digits
2479-meeting-rooms-iii
2681-put-marbles-in-bags
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

Matrix

0073-set-matrix-zeroes
0407-trapping-rain-water-ii
0498-diagonal-traverse
0854-making-a-large-island
0945-snakes-and-ladders
1396-count-servers-that-communicate
1402-count-square-submatrices-with-all-ones
1485-minimum-cost-to-make-at-least-one-valid-path-in-a-grid
1628-count-submatrices-with-all-ones
1876-map-of-highest-peak
2145-grid-game
2160-minimum-operations-to-make-a-uni-value-grid
2685-first-completely-painted-row-or-column
3227-find-missing-and-repeated-values
3459-find-the-minimum-area-to-cover-all-ones-ii
3627-find-minimum-time-to-reach-last-room-i
3628-find-minimum-time-to-reach-last-room-ii
3733-length-of-longest-v-shaped-diagonal-segment

Shortest Path

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

Prefix Sum

1477-product-of-the-last-k-numbers
2145-grid-game
2229-maximum-fruits-harvested-after-at-most-k-steps
2249-count-the-hidden-sequences
2394-count-subarrays-with-score-less-than-k
2529-range-product-queries-of-powers
2915-count-of-interesting-subarrays
3618-find-the-original-typed-string-ii
3639-zero-array-transformation-i
3643-zero-array-transformation-ii
3761-maximum-difference-between-even-and-odd-frequency-ii
3789-maximize-subarrays-after-removing-one-conflicting-pair

Depth-First Search

0386-lexicographical-numbers
0684-redundant-connection
0820-find-eventual-safe-states
0854-making-a-large-island
1093-recover-a-tree-from-preorder-traversal
1350-remove-sub-folders-from-the-filesystem
1396-count-servers-that-communicate
1558-course-schedule-iv
2246-maximum-employees-to-be-invited-to-a-meeting
2400-minimum-score-after-removals-on-a-tree
2438-find-closest-node-to-given-two-nodes
2564-most-profitable-path-in-a-tree
3633-maximize-the-number-of-target-nodes-after-connecting-trees-i
3645-maximize-the-number-of-target-nodes-after-connecting-trees-ii

Union Find

0684-redundant-connection
0854-making-a-large-island
1058-lexicographically-smallest-equivalent-string
1396-count-servers-that-communicate
2583-divide-nodes-into-the-maximum-number-of-groups
3219-make-lexicographically-smallest-array-by-swapping-elements
3348-minimum-cost-walk-in-weighted-graph

Topological Sort

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

Sorting

0075-sort-colors
0368-largest-divisible-subset
0900-reordered-power-of-2
1478-maximum-number-of-events-that-can-be-attended
1851-maximum-number-of-events-that-can-be-attended-ii
2160-minimum-operations-to-make-a-uni-value-grid
2180-maximum-number-of-tasks-you-can-assign
2204-find-subsequence-of-length-k-with-the-largest-sum
2387-partition-array-such-that-maximum-difference-is-k
2473-max-sum-of-a-pair-with-equal-sum-of-digits
2479-meeting-rooms-iii
2681-put-marbles-in-bags
2689-rearranging-fruits
2699-count-the-number-of-fair-pairs
3219-make-lexicographically-smallest-array-by-swapping-elements
3307-find-the-maximum-sum-of-node-values
3321-type-of-triangle
3360-minimum-deletions-to-make-string-k-special
3430-count-days-without-meetings
3657-check-if-grid-can-be-cut-into-sections

Design

1477-product-of-the-last-k-numbers
1995-finding-pairs-with-a-certain-sum
2434-design-a-number-container-system

Ordered Set

2280-count-good-triplets-in-an-array
2434-design-a-number-container-system
3791-fruits-into-baskets-iii

Simulation

0498-diagonal-traverse
2021-remove-all-occurrences-of-a-substring
2048-build-array-from-permutation
2260-divide-a-string-into-groups-of-size-k
2265-partition-array-according-to-given-pivot
2479-meeting-rooms-iii
2551-apply-operations-to-an-array
3332-minimum-operations-to-exceed-threshold-value-ii
3447-clear-digits
3600-find-the-k-th-character-in-string-game-i

Data Stream

1477-product-of-the-last-k-numbers

Backtracking

0679-24-game
1160-letter-tile-possibilities
1516-the-k-th-lexicographical-string-of-all-happy-strings-of-length-n
1819-construct-the-lexicographically-largest-valid-sequence
2140-longest-subsequence-repeated-k-times
2456-construct-smallest-number-from-di-string
2802-find-the-punishment-number-of-an-integer

Tree

1093-recover-a-tree-from-preorder-traversal
2400-minimum-score-after-removals-on-a-tree
2564-most-profitable-path-in-a-tree
3307-find-the-maximum-sum-of-node-values
3633-maximize-the-number-of-target-nodes-after-connecting-trees-i
3645-maximize-the-number-of-target-nodes-after-connecting-trees-ii

Binary Tree

1093-recover-a-tree-from-preorder-traversal

Dynamic Programming

0118-pascals-triangle
0368-largest-divisible-subset
0416-partition-equal-subset-sum
0806-domino-and-tromino-tiling
0826-soup-servings
0868-push-dominoes
0905-length-of-longest-fibonacci-subsequence
0934-bitwise-ors-of-subarrays
1170-shortest-common-supersequence
1402-count-square-submatrices-with-all-ones
1628-count-submatrices-with-all-ones
1849-maximum-absolute-sum-of-any-subarray
1851-maximum-number-of-events-that-can-be-attended-ii
1986-largest-color-value-in-a-directed-graph
2028-the-earliest-and-latest-rounds-where-players-compete
2061-painting-a-grid-with-three-different-colors
2090-number-of-ways-to-arrive-at-destination
2267-minimum-difference-in-sums-after-removal-of-elements
2395-longest-binary-subsequence-less-than-or-equal-to-k
2415-count-the-number-of-ideal-arrays
3142-longest-unequal-adjacent-groups-subsequence-ii
3143-longest-unequal-adjacent-groups-subsequence-i
3243-count-the-number-of-powerful-integers
3307-find-the-maximum-sum-of-node-values
3491-find-the-maximum-length-of-valid-subsequence-ii
3618-find-the-original-typed-string-ii
3629-total-characters-in-string-after-transformations-i
3637-count-number-of-balanced-permutations
3733-length-of-longest-v-shaped-diagonal-segment

Two Pointers

0075-sort-colors
0768-partition-labels
0868-push-dominoes
2265-partition-array-according-to-given-pivot
2551-apply-operations-to-an-array
2699-count-the-number-of-fair-pairs
2707-merge-two-2d-arrays-by-summing-values
3683-find-the-lexicographically-largest-string-from-the-box-i

Number Theory

2415-count-the-number-of-ideal-arrays
2610-closest-prime-numbers-in-range

Sliding Window

1460-number-of-substrings-containing-all-three-characters
1813-maximum-erasure-value
2229-maximum-fruits-harvested-after-at-most-k-steps
2394-count-subarrays-with-score-less-than-k
2463-minimum-recolors-to-get-k-consecutive-black-blocks
2478-longest-nice-subarray
2498-smallest-subarrays-with-maximum-bitwise-or
2527-count-subarrays-with-fixed-bounds
2856-count-complete-subarrays-in-an-array
3483-alternating-groups-ii
3569-count-of-substrings-containing-every-vowel-and-k-consonants-ii
3743-reschedule-meetings-for-maximum-free-time-i
3761-maximum-difference-between-even-and-odd-frequency-ii

Binary Search

1335-maximum-candies-allocated-to-k-children
1851-maximum-number-of-events-that-can-be-attended-ii
2150-kth-smallest-product-of-two-sorted-arrays
2180-maximum-number-of-tasks-you-can-assign
2229-maximum-fruits-harvested-after-at-most-k-steps
2280-count-good-triplets-in-an-array
2394-count-subarrays-with-score-less-than-k
2498-smallest-subarrays-with-maximum-bitwise-or
2665-minimum-time-to-repair-cars
2690-house-robber-iv
2699-count-the-number-of-fair-pairs
3643-zero-array-transformation-ii
3791-fruits-into-baskets-iii

Enumeration

0900-reordered-power-of-2
1656-count-good-triplets
2140-longest-subsequence-repeated-k-times
2202-sum-of-k-mirror-numbers
2998-count-symmetric-integers
3459-find-the-minimum-area-to-cover-all-ones-ii
3548-find-the-count-of-good-integers
3683-find-the-lexicographically-largest-string-from-the-box-i
3741-reschedule-meetings-for-maximum-free-time-ii
3761-maximum-difference-between-even-and-odd-frequency-ii
3789-maximize-subarrays-after-removing-one-conflicting-pair

Combinatorics

2415-count-the-number-of-ideal-arrays
3548-find-the-count-of-good-integers
3637-count-number-of-balanced-permutations
3682-count-the-number-of-arrays-with-k-matching-adjacent-elements

Recursion

0342-power-of-four
2050-count-good-numbers
3600-find-the-k-th-character-in-string-game-i

Divide and Conquer

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

Binary Indexed Tree

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

Segment Tree

2280-count-good-triplets-in-an-array
3789-maximize-subarrays-after-removing-one-conflicting-pair
3791-fruits-into-baskets-iii

Merge Sort

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

Queue

2180-maximum-number-of-tasks-you-can-assign
2527-count-subarrays-with-fixed-bounds

Monotonic Queue

2180-maximum-number-of-tasks-you-can-assign
2527-count-subarrays-with-fixed-bounds

Memoization

1986-largest-color-value-in-a-directed-graph
2028-the-earliest-and-latest-rounds-where-players-compete
2395-longest-binary-subsequence-less-than-or-equal-to-k
3733-length-of-longest-v-shaped-diagonal-segment

Trie

0386-lexicographical-numbers
0440-k-th-smallest-in-lexicographical-order
1350-remove-sub-folders-from-the-filesystem
2079-delete-duplicate-folders-in-system

Hash Function

2079-delete-duplicate-folders-in-system

Probability and Statistics

0826-soup-servings

Monotonic Stack

1628-count-submatrices-with-all-ones