LeetCode-Solutions

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

LeetCode Topics

String

0013-roman-to-integer
0014-longest-common-prefix
0058-length-of-last-word
0125-valid-palindrome
0165-compare-version-numbers
0166-fraction-to-recurring-decimal
0242-valid-anagram
0383-ransom-note
0392-is-subsequence
0782-jewels-and-stones
0812-rotate-string
0920-uncommon-words-from-two-sentences
1058-lexicographically-smallest-equivalent-string
1160-letter-tile-possibilities
1283-reformat-date
1302-delete-characters-to-make-fancy-string
1434-decrypt-string-from-alphabet-to-integer-mapping
1516-the-k-th-lexicographical-string-of-all-happy-strings-of-length-n
1747-lexicographically-smallest-string-after-applying-operations
1781-check-if-two-string-arrays-are-equivalent
1786-count-the-number-of-consistent-strings
1818-maximum-score-from-removing-substrings
1894-merge-strings-alternately
1915-check-if-one-string-swap-can-make-strings-equal
2021-remove-all-occurrences-of-a-substring
2076-sum-of-digits-of-string-after-convert
2093-check-if-string-is-a-prefix-of-array
2107-find-unique-binary-string
2137-final-value-of-variable-after-performing-operations
2154-minimum-moves-to-convert-string
2244-number-of-laser-beams-in-a-bank
2292-counting-words-with-a-given-prefix
2346-largest-3-same-digit-number-in-string
2406-decode-the-message
2456-construct-smallest-number-from-di-string
2502-sort-the-people
2520-using-a-robot-to-print-the-lexicographically-smallest-string
2580-circular-sentence
2599-take-k-of-each-character-from-left-and-right
2887-sort-vowels-in-a-string
3233-maximize-the-number-of-partitions-after-operations
3396-valid-word
3445-lexicographically-minimum-string-after-removing-stars
3447-clear-digits
3451-string-compression-iii
3484-lexicographically-smallest-string-after-a-swap
3533-snake-in-matrix
3618-find-the-original-typed-string-ii
3683-find-the-lexicographically-largest-string-from-the-box-i
3753-maximum-difference-between-even-and-odd-frequency-i
3761-maximum-difference-between-even-and-odd-frequency-ii
3768-check-if-digits-are-equal-in-string-after-operations-i

Array

0011-container-with-most-water
0035-search-insert-position
0036-valid-sudoku
0056-merge-intervals
0066-plus-one
0080-remove-duplicates-from-sorted-array-ii
0088-merge-sorted-array
0118-pascals-triangle
0120-triangle
0121-best-time-to-buy-and-sell-stock
0135-candy
0228-summary-ranges
0407-trapping-rain-water-ii
0417-pacific-atlantic-water-flow
0498-diagonal-traverse
0611-valid-triangle-number
0724-find-pivot-index
0777-toeplitz-matrix
0794-swim-in-rising-water
0925-construct-binary-tree-from-preorder-and-postorder-traversal
0934-bitwise-ors-of-subarrays
0940-fruit-into-baskets
1018-largest-perimeter-triangle
1111-minimum-score-triangulation-of-polygon
1256-rank-transform-of-an-array
1364-tuple-with-same-product
1424-maximum-candies-you-can-get-from-boxes
1426-find-n-unique-integers-sum-up-to-zero
1477-product-of-the-last-k-numbers
1478-maximum-number-of-events-that-can-be-attended
1496-lucky-numbers-in-a-matrix
1510-find-lucky-integer-in-an-array
1612-avoid-flood-in-the-city
1633-minimum-number-of-increments-on-subarrays-to-form-a-target-array
1635-number-of-good-pairs
1677-matrix-diagonal-sum
1679-shortest-subarray-to-be-removed-to-make-array-sorted
1760-check-array-formation-through-concatenation
1781-check-if-two-string-arrays-are-equivalent
1786-count-the-number-of-consistent-strings
1813-maximum-erasure-value
1819-construct-the-lexicographically-largest-valid-sequence
1834-minimum-number-of-people-to-teach
1851-maximum-number-of-events-that-can-be-attended-ii
1876-map-of-highest-peak
1917-maximum-average-pass-ratio
1927-maximum-ascending-subarray-sum
2006-find-the-student-that-will-replace-the-chalk
2093-check-if-string-is-a-prefix-of-array
2107-find-unique-binary-string
2132-convert-1d-array-into-2d-array
2137-final-value-of-variable-after-performing-operations
2148-minimum-number-of-moves-to-seat-everyone
2155-find-missing-observations
2159-two-out-of-three
2169-simple-bank-system
2170-count-number-of-maximum-bitwise-or-subsets
2188-minimized-maximum-of-products-distributed-to-any-store
2244-number-of-laser-beams-in-a-bank
2267-minimum-difference-in-sums-after-removal-of-elements
2292-counting-words-with-a-given-prefix
2324-find-triangular-sum-of-an-array
2331-intersection-of-multiple-arrays
2350-find-closest-number-to-zero
2392-successful-pairs-of-spells-and-potions
2400-minimum-score-after-removals-on-a-tree
2448-count-number-of-bad-pairs
2473-max-sum-of-a-pair-with-equal-sum-of-digits
2498-smallest-subarrays-with-maximum-bitwise-or
2502-sort-the-people
2503-longest-subarray-with-maximum-bitwise-and
2529-range-product-queries-of-powers
2551-apply-operations-to-an-array
2689-rearranging-fruits
2756-buy-two-chocolates
3241-divide-array-into-arrays-with-max-difference
3242-count-elements-with-maximum-frequency
3278-find-the-number-of-ways-to-place-people-i
3307-find-the-maximum-sum-of-node-values
3332-minimum-operations-to-exceed-threshold-value-ii
3434-find-the-number-of-distinct-colors-among-the-balls
3437-maximum-total-damage-with-spell-casting
3446-find-the-number-of-good-pairs-i
3490-find-the-maximum-length-of-valid-subsequence-i
3491-find-the-maximum-length-of-valid-subsequence-ii
3533-snake-in-matrix
3581-the-two-sneaky-numbers-of-digitville
3592-find-x-sum-of-all-k-long-subarrays-ii
3612-adjacent-increasing-subarrays-detection-i
3616-make-array-elements-equal-to-zero
3619-adjacent-increasing-subarrays-detection-ii
3622-maximum-frequency-of-an-element-after-performing-operations-i
3640-maximum-frequency-of-an-element-after-performing-operations-ii
3648-find-the-maximum-number-of-fruits-collected
3741-reschedule-meetings-for-maximum-free-time-ii
3743-reschedule-meetings-for-maximum-free-time-i
3748-sort-matrix-by-diagonals
3788-maximum-unique-subarray-sum-after-deletion
3790-fruits-into-baskets-ii
3791-fruits-into-baskets-iii
3794-find-the-minimum-amount-of-time-to-brew-potions

Hash Table

0013-roman-to-integer
0036-valid-sudoku
0166-fraction-to-recurring-decimal
0242-valid-anagram
0383-ransom-note
0782-jewels-and-stones
0900-reordered-power-of-2
0920-uncommon-words-from-two-sentences
0925-construct-binary-tree-from-preorder-and-postorder-traversal
0940-fruit-into-baskets
1160-letter-tile-possibilities
1256-rank-transform-of-an-array
1364-tuple-with-same-product
1510-find-lucky-integer-in-an-array
1612-avoid-flood-in-the-city
1635-number-of-good-pairs
1760-check-array-formation-through-concatenation
1786-count-the-number-of-consistent-strings
1813-maximum-erasure-value
1834-minimum-number-of-people-to-teach
1915-check-if-one-string-swap-can-make-strings-equal
1986-largest-color-value-in-a-directed-graph
2107-find-unique-binary-string
2159-two-out-of-three
2169-simple-bank-system
2174-next-greater-numerically-balanced-number
2331-intersection-of-multiple-arrays
2406-decode-the-message
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
2520-using-a-robot-to-print-the-lexicographically-smallest-string
2599-take-k-of-each-character-from-left-and-right
2689-rearranging-fruits
3242-count-elements-with-maximum-frequency
3434-find-the-number-of-distinct-colors-among-the-balls
3437-maximum-total-damage-with-spell-casting
3445-lexicographically-minimum-string-after-removing-stars
3446-find-the-number-of-good-pairs-i
3581-the-two-sneaky-numbers-of-digitville
3592-find-x-sum-of-all-k-long-subarrays-ii
3753-maximum-difference-between-even-and-odd-frequency-i
3788-maximum-unique-subarray-sum-after-deletion

Sorting

0056-merge-intervals
0088-merge-sorted-array
0242-valid-anagram
0611-valid-triangle-number
0900-reordered-power-of-2
1018-largest-perimeter-triangle
1256-rank-transform-of-an-array
1478-maximum-number-of-events-that-can-be-attended
1851-maximum-number-of-events-that-can-be-attended-ii
2148-minimum-number-of-moves-to-seat-everyone
2331-intersection-of-multiple-arrays
2392-successful-pairs-of-spells-and-potions
2473-max-sum-of-a-pair-with-equal-sum-of-digits
2502-sort-the-people
2689-rearranging-fruits
2756-buy-two-chocolates
2887-sort-vowels-in-a-string
3241-divide-array-into-arrays-with-max-difference
3278-find-the-number-of-ways-to-place-people-i
3307-find-the-maximum-sum-of-node-values
3437-maximum-total-damage-with-spell-casting
3622-maximum-frequency-of-an-element-after-performing-operations-i
3640-maximum-frequency-of-an-element-after-performing-operations-ii
3748-sort-matrix-by-diagonals

Two Pointers

0011-container-with-most-water
0080-remove-duplicates-from-sorted-array-ii
0088-merge-sorted-array
0125-valid-palindrome
0165-compare-version-numbers
0392-is-subsequence
0611-valid-triangle-number
1679-shortest-subarray-to-be-removed-to-make-array-sorted
1894-merge-strings-alternately
2093-check-if-string-is-a-prefix-of-array
2392-successful-pairs-of-spells-and-potions
2551-apply-operations-to-an-array
3437-maximum-total-damage-with-spell-casting
3683-find-the-lexicographically-largest-string-from-the-box-i

Counting

0383-ransom-note
0900-reordered-power-of-2
0920-uncommon-words-from-two-sentences
1160-letter-tile-possibilities
1364-tuple-with-same-product
1510-find-lucky-integer-in-an-array
1635-number-of-good-pairs
1786-count-the-number-of-consistent-strings
1915-check-if-one-string-swap-can-make-strings-equal
1986-largest-color-value-in-a-directed-graph
2174-next-greater-numerically-balanced-number
2331-intersection-of-multiple-arrays
2448-count-number-of-bad-pairs
3242-count-elements-with-maximum-frequency
3437-maximum-total-damage-with-spell-casting
3753-maximum-difference-between-even-and-odd-frequency-i

Greedy

0011-container-with-most-water
0135-candy
0611-valid-triangle-number
1018-largest-perimeter-triangle
1448-maximum-69-number
1478-maximum-number-of-events-that-can-be-attended
1612-avoid-flood-in-the-city
1633-minimum-number-of-increments-on-subarrays-to-form-a-target-array
1818-maximum-score-from-removing-substrings
1834-minimum-number-of-people-to-teach
1917-maximum-average-pass-ratio
2148-minimum-number-of-moves-to-seat-everyone
2154-minimum-moves-to-convert-string
2456-construct-smallest-number-from-di-string
2520-using-a-robot-to-print-the-lexicographically-smallest-string
2689-rearranging-fruits
2715-k-items-with-the-maximum-sum
2756-buy-two-chocolates
3241-divide-array-into-arrays-with-max-difference
3307-find-the-maximum-sum-of-node-values
3445-lexicographically-minimum-string-after-removing-stars
3484-lexicographically-smallest-string-after-a-swap
3741-reschedule-meetings-for-maximum-free-time-ii
3743-reschedule-meetings-for-maximum-free-time-i
3788-maximum-unique-subarray-sum-after-deletion

Math

0009-palindrome-number
0013-roman-to-integer
0066-plus-one
0069-sqrtx
0166-fraction-to-recurring-decimal
0231-power-of-two
0326-power-of-three
0826-soup-servings
0900-reordered-power-of-2
1018-largest-perimeter-triangle
1411-convert-binary-number-in-a-linked-list-to-integer
1426-find-n-unique-integers-sum-up-to-zero
1448-maximum-69-number
1477-product-of-the-last-k-numbers
1635-number-of-good-pairs
1642-water-bottles
1817-calculate-money-in-leetcode-bank
2155-find-missing-observations
2174-next-greater-numerically-balanced-number
2244-number-of-laser-beams-in-a-bank
2324-find-triangular-sum-of-an-array
2448-count-number-of-bad-pairs
2715-k-items-with-the-maximum-sum
2802-find-the-punishment-number-of-an-integer
3172-divisible-and-non-divisible-sums-difference
3201-distribute-candies-among-children-ii
3278-find-the-number-of-ways-to-place-people-i
3279-alice-and-bob-playing-flower-game
3336-water-bottles-ii
3511-find-the-winning-player-in-coin-game
3581-the-two-sneaky-numbers-of-digitville
3600-find-the-k-th-character-in-string-game-i
3601-find-the-k-th-character-in-string-game-ii
3676-smallest-number-with-all-set-bits
3768-check-if-digits-are-equal-in-string-after-operations-i
3830-find-closest-person

Prefix Sum

0724-find-pivot-index
1477-product-of-the-last-k-numbers
2006-find-the-student-that-will-replace-the-chalk
2529-range-product-queries-of-powers
3616-make-array-elements-equal-to-zero
3618-find-the-original-typed-string-ii
3622-maximum-frequency-of-an-element-after-performing-operations-i
3640-maximum-frequency-of-an-element-after-performing-operations-ii
3761-maximum-difference-between-even-and-odd-frequency-ii
3794-find-the-minimum-amount-of-time-to-brew-potions

Binary Search

0035-search-insert-position
0069-sqrtx
0611-valid-triangle-number
0794-swim-in-rising-water
1612-avoid-flood-in-the-city
1679-shortest-subarray-to-be-removed-to-make-array-sorted
1851-maximum-number-of-events-that-can-be-attended-ii
2006-find-the-student-that-will-replace-the-chalk
2188-minimized-maximum-of-products-distributed-to-any-store
2392-successful-pairs-of-spells-and-potions
2498-smallest-subarrays-with-maximum-bitwise-or
3437-maximum-total-damage-with-spell-casting
3619-adjacent-increasing-subarrays-detection-ii
3622-maximum-frequency-of-an-element-after-performing-operations-i
3640-maximum-frequency-of-an-element-after-performing-operations-ii
3790-fruits-into-baskets-ii
3791-fruits-into-baskets-iii

Bit Manipulation

0231-power-of-two
0934-bitwise-ors-of-subarrays
1786-count-the-number-of-consistent-strings
2159-two-out-of-three
2170-count-number-of-maximum-bitwise-or-subsets
2400-minimum-score-after-removals-on-a-tree
2498-smallest-subarrays-with-maximum-bitwise-or
2503-longest-subarray-with-maximum-bitwise-and
2529-range-product-queries-of-powers
3233-maximize-the-number-of-partitions-after-operations
3307-find-the-maximum-sum-of-node-values
3508-number-of-bit-changes-to-make-two-integers-equal
3600-find-the-k-th-character-in-string-game-i
3601-find-the-k-th-character-in-string-game-ii
3676-smallest-number-with-all-set-bits

Counting Sort

2148-minimum-number-of-moves-to-seat-everyone

Simulation

0498-diagonal-traverse
1642-water-bottles
2006-find-the-student-that-will-replace-the-chalk
2021-remove-all-occurrences-of-a-substring
2076-sum-of-digits-of-string-after-convert
2132-convert-1d-array-into-2d-array
2137-final-value-of-variable-after-performing-operations
2155-find-missing-observations
2169-simple-bank-system
2324-find-triangular-sum-of-an-array
2551-apply-operations-to-an-array
3332-minimum-operations-to-exceed-threshold-value-ii
3336-water-bottles-ii
3434-find-the-number-of-distinct-colors-among-the-balls
3447-clear-digits
3511-find-the-winning-player-in-coin-game
3533-snake-in-matrix
3600-find-the-k-th-character-in-string-game-i
3616-make-array-elements-equal-to-zero
3768-check-if-digits-are-equal-in-string-after-operations-i
3790-fruits-into-baskets-ii
3794-find-the-minimum-amount-of-time-to-brew-potions

Game Theory

3511-find-the-winning-player-in-coin-game

Matrix

0036-valid-sudoku
0407-trapping-rain-water-ii
0417-pacific-atlantic-water-flow
0498-diagonal-traverse
0777-toeplitz-matrix
0794-swim-in-rising-water
1496-lucky-numbers-in-a-matrix
1677-matrix-diagonal-sum
1876-map-of-highest-peak
2132-convert-1d-array-into-2d-array
2244-number-of-laser-beams-in-a-bank
3648-find-the-maximum-number-of-fruits-collected
3748-sort-matrix-by-diagonals

Trie

0014-longest-common-prefix
0440-k-th-smallest-in-lexicographical-order

Dynamic Programming

0118-pascals-triangle
0120-triangle
0121-best-time-to-buy-and-sell-stock
0392-is-subsequence
0826-soup-servings
0934-bitwise-ors-of-subarrays
1111-minimum-score-triangulation-of-polygon
1633-minimum-number-of-increments-on-subarrays-to-form-a-target-array
1851-maximum-number-of-events-that-can-be-attended-ii
1986-largest-color-value-in-a-directed-graph
2267-minimum-difference-in-sums-after-removal-of-elements
2882-ways-to-express-an-integer-as-sum-of-powers
3233-maximize-the-number-of-partitions-after-operations
3307-find-the-maximum-sum-of-node-values
3437-maximum-total-damage-with-spell-casting
3490-find-the-maximum-length-of-valid-subsequence-i
3491-find-the-maximum-length-of-valid-subsequence-ii
3618-find-the-original-typed-string-ii
3648-find-the-maximum-number-of-fruits-collected

Database

0175-combine-two-tables
0177-nth-highest-salary
0178-rank-scores
0180-consecutive-numbers
0181-employees-earning-more-than-their-managers
0182-duplicate-emails
0183-customers-who-never-order
0184-department-highest-salary
0196-delete-duplicate-emails
0577-employee-bonus
0620-not-boring-movies
1135-customers-who-bought-all-products
1161-project-employees-i
1258-article-views-i
1509-replace-employee-id-with-the-unique-identifier
1724-customer-who-visited-but-did-not-make-any-transactions
1773-percentage-of-users-attended-a-contest
1827-invalid-tweets

String Matching

0812-rotate-string
2292-counting-words-with-a-given-prefix

Stack

1633-minimum-number-of-increments-on-subarrays-to-form-a-target-array
1679-shortest-subarray-to-be-removed-to-make-array-sorted
1818-maximum-score-from-removing-substrings
2021-remove-all-occurrences-of-a-substring
2456-construct-smallest-number-from-di-string
2520-using-a-robot-to-print-the-lexicographically-smallest-string
3445-lexicographically-minimum-string-after-removing-stars
3447-clear-digits

Monotonic Stack

1633-minimum-number-of-increments-on-subarrays-to-form-a-target-array
1679-shortest-subarray-to-be-removed-to-make-array-sorted

Graph

1424-maximum-candies-you-can-get-from-boxes
1916-find-center-of-star-graph
1986-largest-color-value-in-a-directed-graph
2438-find-closest-node-to-given-two-nodes

Sliding Window

0940-fruit-into-baskets
1813-maximum-erasure-value
2498-smallest-subarrays-with-maximum-bitwise-or
2599-take-k-of-each-character-from-left-and-right
3592-find-x-sum-of-all-k-long-subarrays-ii
3622-maximum-frequency-of-an-element-after-performing-operations-i
3640-maximum-frequency-of-an-element-after-performing-operations-ii
3743-reschedule-meetings-for-maximum-free-time-i
3761-maximum-difference-between-even-and-odd-frequency-ii

Breadth-First Search

0407-trapping-rain-water-ii
0417-pacific-atlantic-water-flow
0794-swim-in-rising-water
1424-maximum-candies-you-can-get-from-boxes
1747-lexicographically-smallest-string-after-applying-operations
1876-map-of-highest-peak
3633-maximize-the-number-of-target-nodes-after-connecting-trees-i
3645-maximize-the-number-of-target-nodes-after-connecting-trees-ii

Design

1477-product-of-the-last-k-numbers
2169-simple-bank-system
2434-design-a-number-container-system

Heap (Priority Queue)

0407-trapping-rain-water-ii
0794-swim-in-rising-water
1478-maximum-number-of-events-that-can-be-attended
1612-avoid-flood-in-the-city
1917-maximum-average-pass-ratio
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
3332-minimum-operations-to-exceed-threshold-value-ii
3445-lexicographically-minimum-string-after-removing-stars
3592-find-x-sum-of-all-k-long-subarrays-ii

Ordered Set

2434-design-a-number-container-system
3790-fruits-into-baskets-ii
3791-fruits-into-baskets-iii

Data Stream

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

Backtracking

1160-letter-tile-possibilities
1516-the-k-th-lexicographical-string-of-all-happy-strings-of-length-n
1819-construct-the-lexicographically-largest-valid-sequence
2107-find-unique-binary-string
2170-count-number-of-maximum-bitwise-or-subsets
2174-next-greater-numerically-balanced-number
2456-construct-smallest-number-from-di-string
2802-find-the-punishment-number-of-an-integer

Divide and Conquer

0925-construct-binary-tree-from-preorder-and-postorder-traversal

Tree

0925-construct-binary-tree-from-preorder-and-postorder-traversal
2400-minimum-score-after-removals-on-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

0925-construct-binary-tree-from-preorder-and-postorder-traversal

Topological Sort

1986-largest-color-value-in-a-directed-graph

Memoization

1986-largest-color-value-in-a-directed-graph

Depth-First Search

0417-pacific-atlantic-water-flow
0794-swim-in-rising-water
1747-lexicographically-smallest-string-after-applying-operations
2400-minimum-score-after-removals-on-a-tree
2438-find-closest-node-to-given-two-nodes
3633-maximize-the-number-of-target-nodes-after-connecting-trees-i
3645-maximize-the-number-of-target-nodes-after-connecting-trees-ii

Combinatorics

2324-find-triangular-sum-of-an-array
3201-distribute-candies-among-children-ii
3768-check-if-digits-are-equal-in-string-after-operations-i

Enumeration

0900-reordered-power-of-2
1747-lexicographically-smallest-string-after-applying-operations
2170-count-number-of-maximum-bitwise-or-subsets
2174-next-greater-numerically-balanced-number
3201-distribute-candies-among-children-ii
3278-find-the-number-of-ways-to-place-people-i
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

Union Find

0794-swim-in-rising-water
1058-lexicographically-smallest-equivalent-string

Recursion

0231-power-of-two
0326-power-of-three
3600-find-the-k-th-character-in-string-game-i
3601-find-the-k-th-character-in-string-game-ii

Linked List

1411-convert-binary-number-in-a-linked-list-to-integer

Brainteaser

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

Segment Tree

3790-fruits-into-baskets-ii
3791-fruits-into-baskets-iii

Probability and Statistics

0826-soup-servings

Geometry

3278-find-the-number-of-ways-to-place-people-i

Bitmask

3233-maximize-the-number-of-partitions-after-operations

Number Theory

3768-check-if-digits-are-equal-in-string-after-operations-i