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

LeetCode Topics

Array

0001-two-sum
0004-median-of-two-sorted-arrays
0015-3sum
0016-3sum-closest
0018-4sum
0026-remove-duplicates-from-sorted-array
0033-search-in-rotated-sorted-array
0036-valid-sudoku
0041-first-missing-positive
0042-trapping-rain-water
0045-jump-game-ii
0046-permutations
0054-spiral-matrix
0055-jump-game
0064-minimum-path-sum
0066-plus-one
0074-search-a-2d-matrix
0081-search-in-rotated-sorted-array-ii
0088-merge-sorted-array
0121-best-time-to-buy-and-sell-stock
0122-best-time-to-buy-and-sell-stock-ii
0134-gas-station
0135-candy
0137-single-number-ii
0153-find-minimum-in-rotated-sorted-array
0169-majority-element
0179-largest-number
0215-kth-largest-element-in-an-array
0229-majority-element-ii
0238-product-of-array-except-self
0260-single-number-iii
0274-h-index
0275-h-index-ii
0287-find-the-duplicate-number
0347-top-k-frequent-elements
0349-intersection-of-two-arrays
0350-intersection-of-two-arrays-ii
0378-kth-smallest-element-in-a-sorted-matrix
0442-find-all-duplicates-in-an-array
0448-find-all-numbers-disappeared-in-an-array
0494-target-sum
0539-minimum-time-difference
0624-maximum-distance-in-arrays
0643-maximum-average-subarray-i
0645-set-mismatch
0745-find-smallest-letter-greater-than-target
0780-max-chunks-to-make-sorted
0792-binary-search
0878-shifting-letters
0907-koko-eating-bananas
0917-boats-to-save-people
0948-sort-an-array
0950-x-of-a-kind-in-a-deck-of-cards
0979-di-string-match
1002-maximum-width-ramp
1014-k-closest-points-to-origin
1031-add-to-array-form-of-integer
1096-maximum-sum-of-two-non-overlapping-subarrays
1112-find-words-that-can-be-formed-by-characters
1256-rank-transform-of-an-array
1335-maximum-candies-allocated-to-k-children
1350-remove-sub-folders-from-the-filesystem
1428-jump-game-iii
1449-print-words-vertically
1468-check-if-n-and-its-double-exist
1482-how-many-numbers-are-smaller-than-the-current-number
1486-find-the-distance-value-between-two-arrays
1570-final-prices-with-a-special-discount-in-a-shop
1586-longest-subarray-of-1s-after-deleting-one-element
1615-range-sum-of-sorted-subarray-sums
1635-number-of-good-pairs
1646-kth-missing-positive-number
1675-magnetic-force-between-two-balls
1741-sort-array-by-increasing-frequency
1755-defuse-the-bomb
1886-minimum-limit-of-balls-in-a-bag
1895-minimum-number-of-operations-to-move-all-balls-to-each-box
1940-maximum-xor-for-each-query
1972-rotating-the-box
2089-maximum-matrix-sum
2094-remove-stones-to-minimize-the-total
2106-find-greatest-common-divisor-of-array
2107-find-unique-binary-string
2113-find-the-kth-largest-integer-in-the-array
2132-convert-1d-array-into-2d-array
2155-find-missing-observations
2164-two-best-non-overlapping-events
2188-minimized-maximum-of-products-distributed-to-any-store
2210-find-target-indices-after-sorting-array
2232-adding-spaces-to-a-string
2269-count-elements-with-strictly-smaller-and-greater-elements
2292-counting-words-with-a-given-prefix
2324-find-triangular-sum-of-an-array
2341-count-prefixes-of-a-given-string
2358-number-of-ways-to-split-array
2386-min-max-game
2465-shifting-letters-ii
2473-max-sum-of-a-pair-with-equal-sum-of-digits
2503-longest-subarray-with-maximum-bitwise-and
2533-bitwise-xor-of-all-pairings
2581-divide-players-into-teams-of-equal-skill
2586-longest-square-streak-in-an-array
2598-shortest-distance-to-target-string-in-a-circular-array
2616-maximal-score-after-applying-k-operations
2634-minimum-common-value
2636-maximum-subsequence-score
2640-maximum-number-of-integers-to-choose-from-a-range-i
2691-count-vowel-strings-in-ranges
2692-take-gifts-from-the-richest-pile
2695-find-score-of-an-array-after-marking-all-elements
2766-find-the-prefix-common-array-of-two-arrays
2868-continuous-subarrays
2891-maximum-beauty-of-an-array-after-applying-operation
2902-max-pair-sum-in-an-array
2917-count-pairs-whose-sum-is-less-than-target
3194-find-words-containing-character
3227-find-missing-and-repeated-values
3291-find-if-array-can-be-sorted
3309-count-prefix-and-suffix-pairs-i
3332-minimum-operations-to-exceed-threshold-value-ii
3381-shortest-subarray-with-or-at-least-k-i
3427-special-array-ii
3446-find-the-number-of-good-pairs-i
3507-find-the-count-of-numbers-which-are-not-special
3522-find-the-power-of-k-size-subarrays-i
3555-final-array-state-after-k-multiplication-operations-i
3605-construct-the-minimum-bitwise-array-i
3612-adjacent-increasing-subarrays-detection-i
3649-minimum-time-to-break-locks-i

Math

0007-reverse-integer
0013-roman-to-integer
0066-plus-one
0067-add-binary
0069-sqrtx
0070-climbing-stairs
0202-happy-number
0231-power-of-two
0263-ugly-number
0264-ugly-number-ii
0273-integer-to-english-words
0326-power-of-three
0342-power-of-four
0367-valid-perfect-square
0415-add-strings
0441-arranging-coins
0539-minimum-time-difference
0670-maximum-swap
0950-x-of-a-kind-in-a-deck-of-cards
1013-fibonacci-number
1014-k-closest-points-to-origin
1031-add-to-array-form-of-integer
1086-divisor-game
1444-number-of-steps-to-reduce-a-number-to-zero
1635-number-of-good-pairs
1642-water-bottles
2050-count-good-numbers
2106-find-greatest-common-divisor-of-array
2155-find-missing-observations
2324-find-triangular-sum-of-an-array
2608-count-the-digits-that-divide-a-number
2802-find-the-punishment-number-of-an-integer
3227-find-missing-and-repeated-values
3275-minimum-number-of-pushes-to-type-word-i
3507-find-the-count-of-numbers-which-are-not-special
3555-final-array-state-after-k-multiplication-operations-i
3600-find-the-k-th-character-in-string-game-i

Simulation

0054-spiral-matrix
0067-add-binary
0415-add-strings
1449-print-words-vertically
1642-water-bottles
1667-find-kth-bit-in-nth-binary-string
2132-convert-1d-array-into-2d-array
2155-find-missing-observations
2232-adding-spaces-to-a-string
2324-find-triangular-sum-of-an-array
2386-min-max-game
2692-take-gifts-from-the-richest-pile
2695-find-score-of-an-array-after-marking-all-elements
2800-minimum-string-length-after-removing-substrings
3332-minimum-operations-to-exceed-threshold-value-ii
3447-clear-digits
3555-final-array-state-after-k-multiplication-operations-i
3600-find-the-k-th-character-in-string-game-i

Greedy

0045-jump-game-ii
0055-jump-game
0122-best-time-to-buy-and-sell-stock-ii
0134-gas-station
0135-candy
0179-largest-number
0624-maximum-distance-in-arrays
0670-maximum-swap
0778-reorganize-string
0780-max-chunks-to-make-sorted
0917-boats-to-save-people
0957-minimum-add-to-make-parentheses-valid
0979-di-string-match
1502-construct-k-palindrome-strings
2089-maximum-matrix-sum
2094-remove-stones-to-minimize-the-total
2095-minimum-number-of-swaps-to-make-the-string-balanced
2300-construct-string-with-repeat-limit
2337-remove-digit-from-number-to-maximize-result
2456-construct-smallest-number-from-di-string
2509-minimize-xor
2616-maximal-score-after-applying-k-operations
2636-maximum-subsequence-score
2640-maximum-number-of-integers-to-choose-from-a-range-i
3195-separate-black-and-white-balls
3275-minimum-number-of-pushes-to-type-word-i

Hash Table

0001-two-sum
0003-longest-substring-without-repeating-characters
0013-roman-to-integer
0036-valid-sudoku
0041-first-missing-positive
0169-majority-element
0202-happy-number
0229-majority-element-ii
0242-valid-anagram
0264-ugly-number-ii
0347-top-k-frequent-elements
0349-intersection-of-two-arrays
0350-intersection-of-two-arrays-ii
0383-ransom-note
0387-first-unique-character-in-a-string
0442-find-all-duplicates-in-an-array
0448-find-all-numbers-disappeared-in-an-array
0451-sort-characters-by-frequency
0645-set-mismatch
0778-reorganize-string
0920-uncommon-words-from-two-sentences
0950-x-of-a-kind-in-a-deck-of-cards
1112-find-words-that-can-be-formed-by-characters
1256-rank-transform-of-an-array
1468-check-if-n-and-its-double-exist
1482-how-many-numbers-are-smaller-than-the-current-number
1502-construct-k-palindrome-strings
1635-number-of-good-pairs
1741-sort-array-by-increasing-frequency
1904-second-largest-digit-in-a-string
1915-check-if-one-string-swap-can-make-strings-equal
2107-find-unique-binary-string
2300-construct-string-with-repeat-limit
2427-first-letter-to-appear-twice
2473-max-sum-of-a-pair-with-equal-sum-of-digits
2581-divide-players-into-teams-of-equal-skill
2586-longest-square-streak-in-an-array
2634-minimum-common-value
2640-maximum-number-of-integers-to-choose-from-a-range-i
2695-find-score-of-an-array-after-marking-all-elements
2766-find-the-prefix-common-array-of-two-arrays
2902-max-pair-sum-in-an-array
3227-find-missing-and-repeated-values
3267-find-longest-special-substring-that-occurs-thrice-i
3446-find-the-number-of-good-pairs-i
3455-minimum-length-of-string-after-operations
3595-rearrange-k-substrings-to-form-target-string

Matrix

0036-valid-sudoku
0054-spiral-matrix
0064-minimum-path-sum
0074-search-a-2d-matrix
0378-kth-smallest-element-in-a-sorted-matrix
1972-rotating-the-box
2089-maximum-matrix-sum
2132-convert-1d-array-into-2d-array
3227-find-missing-and-repeated-values

Bit Manipulation

0067-add-binary
0137-single-number-ii
0231-power-of-two
0260-single-number-iii
0287-find-the-duplicate-number
0342-power-of-four
0645-set-mismatch
1444-number-of-steps-to-reduce-a-number-to-zero
1940-maximum-xor-for-each-query
2323-minimum-bit-flips-to-convert-number
2427-first-letter-to-appear-twice
2503-longest-subarray-with-maximum-bitwise-and
2509-minimize-xor
2533-bitwise-xor-of-all-pairings
2766-find-the-prefix-common-array-of-two-arrays
3291-find-if-array-can-be-sorted
3381-shortest-subarray-with-or-at-least-k-i
3600-find-the-k-th-character-in-string-game-i
3605-construct-the-minimum-bitwise-array-i
3649-minimum-time-to-break-locks-i

Brainteaser

1086-divisor-game
2503-longest-subarray-with-maximum-bitwise-and
2533-bitwise-xor-of-all-pairings

String

0003-longest-substring-without-repeating-characters
0013-roman-to-integer
0014-longest-common-prefix
0020-valid-parentheses
0028-find-the-index-of-the-first-occurrence-in-a-string
0058-length-of-last-word
0067-add-binary
0151-reverse-words-in-a-string
0179-largest-number
0242-valid-anagram
0273-integer-to-english-words
0383-ransom-note
0387-first-unique-character-in-a-string
0392-is-subsequence
0415-add-strings
0451-sort-characters-by-frequency
0539-minimum-time-difference
0541-reverse-string-ii
0551-student-attendance-record-i
0557-reverse-words-in-a-string-iii
0778-reorganize-string
0878-shifting-letters
0920-uncommon-words-from-two-sentences
0957-minimum-add-to-make-parentheses-valid
0979-di-string-match
1112-find-words-that-can-be-formed-by-characters
1350-remove-sub-folders-from-the-filesystem
1449-print-words-vertically
1502-construct-k-palindrome-strings
1537-maximum-score-after-splitting-a-string
1566-check-if-a-word-occurs-as-a-prefix-of-any-word-in-a-sentence
1667-find-kth-bit-in-nth-binary-string
1895-minimum-number-of-operations-to-move-all-balls-to-each-box
1904-second-largest-digit-in-a-string
1915-check-if-one-string-swap-can-make-strings-equal
2095-minimum-number-of-swaps-to-make-the-string-balanced
2107-find-unique-binary-string
2113-find-the-kth-largest-integer-in-the-array
2232-adding-spaces-to-a-string
2292-counting-words-with-a-given-prefix
2300-construct-string-with-repeat-limit
2337-remove-digit-from-number-to-maximize-result
2341-count-prefixes-of-a-given-string
2414-move-pieces-to-obtain-a-string
2427-first-letter-to-appear-twice
2456-construct-smallest-number-from-di-string
2465-shifting-letters-ii
2580-circular-sentence
2598-shortest-distance-to-target-string-in-a-circular-array
2691-count-vowel-strings-in-ranges
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
3194-find-words-containing-character
3195-separate-black-and-white-balls
3267-find-longest-special-substring-that-occurs-thrice-i
3275-minimum-number-of-pushes-to-type-word-i
3309-count-prefix-and-suffix-pairs-i
3447-clear-digits
3451-string-compression-iii
3455-minimum-length-of-string-after-operations
3595-rearrange-k-substrings-to-form-target-string

Sorting

0015-3sum
0016-3sum-closest
0018-4sum
0088-merge-sorted-array
0169-majority-element
0179-largest-number
0215-kth-largest-element-in-an-array
0229-majority-element-ii
0242-valid-anagram
0274-h-index
0347-top-k-frequent-elements
0349-intersection-of-two-arrays
0350-intersection-of-two-arrays-ii
0378-kth-smallest-element-in-a-sorted-matrix
0451-sort-characters-by-frequency
0539-minimum-time-difference
0645-set-mismatch
0778-reorganize-string
0780-max-chunks-to-make-sorted
0917-boats-to-save-people
0948-sort-an-array
1014-k-closest-points-to-origin
1256-rank-transform-of-an-array
1468-check-if-n-and-its-double-exist
1482-how-many-numbers-are-smaller-than-the-current-number
1486-find-the-distance-value-between-two-arrays
1615-range-sum-of-sorted-subarray-sums
1675-magnetic-force-between-two-balls
1741-sort-array-by-increasing-frequency
2113-find-the-kth-largest-integer-in-the-array
2164-two-best-non-overlapping-events
2210-find-target-indices-after-sorting-array
2269-count-elements-with-strictly-smaller-and-greater-elements
2473-max-sum-of-a-pair-with-equal-sum-of-digits
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
2695-find-score-of-an-array-after-marking-all-elements
2891-maximum-beauty-of-an-array-after-applying-operation
2917-count-pairs-whose-sum-is-less-than-target
3291-find-if-array-can-be-sorted
3595-rearrange-k-substrings-to-form-target-string

Counting

0169-majority-element
0229-majority-element-ii
0347-top-k-frequent-elements
0383-ransom-note
0387-first-unique-character-in-a-string
0451-sort-characters-by-frequency
0778-reorganize-string
0920-uncommon-words-from-two-sentences
0950-x-of-a-kind-in-a-deck-of-cards
1112-find-words-that-can-be-formed-by-characters
1482-how-many-numbers-are-smaller-than-the-current-number
1502-construct-k-palindrome-strings
1635-number-of-good-pairs
1915-check-if-one-string-swap-can-make-strings-equal
2269-count-elements-with-strictly-smaller-and-greater-elements
2300-construct-string-with-repeat-limit
2427-first-letter-to-appear-twice
3267-find-longest-special-substring-that-occurs-thrice-i
3455-minimum-length-of-string-after-operations

Binary Search

0004-median-of-two-sorted-arrays
0033-search-in-rotated-sorted-array
0069-sqrtx
0074-search-a-2d-matrix
0081-search-in-rotated-sorted-array-ii
0153-find-minimum-in-rotated-sorted-array
0275-h-index-ii
0278-first-bad-version
0287-find-the-duplicate-number
0349-intersection-of-two-arrays
0350-intersection-of-two-arrays-ii
0367-valid-perfect-square
0374-guess-number-higher-or-lower
0378-kth-smallest-element-in-a-sorted-matrix
0441-arranging-coins
0745-find-smallest-letter-greater-than-target
0792-binary-search
0907-koko-eating-bananas
1335-maximum-candies-allocated-to-k-children
1468-check-if-n-and-its-double-exist
1486-find-the-distance-value-between-two-arrays
1615-range-sum-of-sorted-subarray-sums
1646-kth-missing-positive-number
1675-magnetic-force-between-two-balls
1886-minimum-limit-of-balls-in-a-bag
2164-two-best-non-overlapping-events
2188-minimized-maximum-of-products-distributed-to-any-store
2210-find-target-indices-after-sorting-array
2586-longest-square-streak-in-an-array
2634-minimum-common-value
2640-maximum-number-of-integers-to-choose-from-a-range-i
2891-maximum-beauty-of-an-array-after-applying-operation
2917-count-pairs-whose-sum-is-less-than-target
3267-find-longest-special-substring-that-occurs-thrice-i
3427-special-array-ii

Number Theory

0950-x-of-a-kind-in-a-deck-of-cards
2106-find-greatest-common-divisor-of-array
3507-find-the-count-of-numbers-which-are-not-special

Backtracking

0046-permutations
0494-target-sum
2107-find-unique-binary-string
2456-construct-smallest-number-from-di-string
2802-find-the-punishment-number-of-an-integer
3649-minimum-time-to-break-locks-i

Recursion

0231-power-of-two
0273-integer-to-english-words
0326-power-of-three
0342-power-of-four
1013-fibonacci-number
1667-find-kth-bit-in-nth-binary-string
2050-count-good-numbers
3600-find-the-k-th-character-in-string-game-i

Two Pointers

0015-3sum
0016-3sum-closest
0018-4sum
0026-remove-duplicates-from-sorted-array
0028-find-the-index-of-the-first-occurrence-in-a-string
0042-trapping-rain-water
0088-merge-sorted-array
0151-reverse-words-in-a-string
0202-happy-number
0287-find-the-duplicate-number
0349-intersection-of-two-arrays
0350-intersection-of-two-arrays-ii
0392-is-subsequence
0541-reverse-string-ii
0557-reverse-words-in-a-string-iii
0917-boats-to-save-people
0979-di-string-match
1468-check-if-n-and-its-double-exist
1486-find-the-distance-value-between-two-arrays
1566-check-if-a-word-occurs-as-a-prefix-of-any-word-in-a-sentence
1615-range-sum-of-sorted-subarray-sums
1972-rotating-the-box
2095-minimum-number-of-swaps-to-make-the-string-balanced
2232-adding-spaces-to-a-string
2414-move-pieces-to-obtain-a-string
2581-divide-players-into-teams-of-equal-skill
2634-minimum-common-value
2917-count-pairs-whose-sum-is-less-than-target
3018-make-string-a-subsequence-using-cyclic-increments
3195-separate-black-and-white-balls

Divide and Conquer

0004-median-of-two-sorted-arrays
0169-majority-element
0215-kth-largest-element-in-an-array
0347-top-k-frequent-elements
0948-sort-an-array
1014-k-closest-points-to-origin
2113-find-the-kth-largest-integer-in-the-array

Dynamic Programming

0042-trapping-rain-water
0045-jump-game-ii
0055-jump-game
0064-minimum-path-sum
0070-climbing-stairs
0121-best-time-to-buy-and-sell-stock
0122-best-time-to-buy-and-sell-stock-ii
0264-ugly-number-ii
0392-is-subsequence
0494-target-sum
1013-fibonacci-number
1086-divisor-game
1096-maximum-sum-of-two-non-overlapping-subarrays
1586-longest-subarray-of-1s-after-deleting-one-element
2164-two-best-non-overlapping-events
2586-longest-square-streak-in-an-array
3649-minimum-time-to-break-locks-i

Game Theory

1086-divisor-game

Interactive

0278-first-bad-version
0374-guess-number-higher-or-lower

Stack

0020-valid-parentheses
0042-trapping-rain-water
0780-max-chunks-to-make-sorted
0957-minimum-add-to-make-parentheses-valid
1002-maximum-width-ramp
1570-final-prices-with-a-special-discount-in-a-shop
2095-minimum-number-of-swaps-to-make-the-string-balanced
2456-construct-smallest-number-from-di-string
2800-minimum-string-length-after-removing-substrings
3447-clear-digits

Monotonic Stack

0042-trapping-rain-water
0780-max-chunks-to-make-sorted
1002-maximum-width-ramp
1570-final-prices-with-a-special-discount-in-a-shop

Memoization

0070-climbing-stairs
1013-fibonacci-number

Prefix Sum

0238-product-of-array-except-self
0878-shifting-letters
1537-maximum-score-after-splitting-a-string
1895-minimum-number-of-operations-to-move-all-balls-to-each-box
1940-maximum-xor-for-each-query
2358-number-of-ways-to-split-array
2465-shifting-letters-ii
2691-count-vowel-strings-in-ranges
3427-special-array-ii

Depth-First Search

1350-remove-sub-folders-from-the-filesystem
1428-jump-game-iii

Trie

0014-longest-common-prefix
1350-remove-sub-folders-from-the-filesystem
3309-count-prefix-and-suffix-pairs-i

Sliding Window

0003-longest-substring-without-repeating-characters
0643-maximum-average-subarray-i
1096-maximum-sum-of-two-non-overlapping-subarrays
1586-longest-subarray-of-1s-after-deleting-one-element
1755-defuse-the-bomb
2868-continuous-subarrays
2891-maximum-beauty-of-an-array-after-applying-operation
3267-find-longest-special-substring-that-occurs-thrice-i
3381-shortest-subarray-with-or-at-least-k-i
3522-find-the-power-of-k-size-subarrays-i

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
2292-counting-words-with-a-given-prefix
3309-count-prefix-and-suffix-pairs-i

Geometry

1014-k-closest-points-to-origin

Heap (Priority Queue)

0215-kth-largest-element-in-an-array
0264-ugly-number-ii
0347-top-k-frequent-elements
0378-kth-smallest-element-in-a-sorted-matrix
0451-sort-characters-by-frequency
0778-reorganize-string
0948-sort-an-array
1014-k-closest-points-to-origin
2094-remove-stones-to-minimize-the-total
2113-find-the-kth-largest-integer-in-the-array
2164-two-best-non-overlapping-events
2300-construct-string-with-repeat-limit
2473-max-sum-of-a-pair-with-equal-sum-of-digits
2616-maximal-score-after-applying-k-operations
2636-maximum-subsequence-score
2692-take-gifts-from-the-richest-pile
2695-find-score-of-an-array-after-marking-all-elements
2868-continuous-subarrays
3332-minimum-operations-to-exceed-threshold-value-ii
3555-final-array-state-after-k-multiplication-operations-i

Quickselect

0215-kth-largest-element-in-an-array
0347-top-k-frequent-elements
1014-k-closest-points-to-origin
2113-find-the-kth-largest-integer-in-the-array

Merge Sort

0948-sort-an-array

Bucket Sort

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

Radix Sort

0948-sort-an-array

Counting Sort

0274-h-index
0948-sort-an-array

Queue

0387-first-unique-character-in-a-string
2868-continuous-subarrays

Ordered Set

2868-continuous-subarrays

Monotonic Queue

2868-continuous-subarrays

Combinatorics

2324-find-triangular-sum-of-an-array

Enumeration

2337-remove-digit-from-number-to-maximize-result

Bitmask

3649-minimum-time-to-break-locks-i

Rolling Hash

3309-count-prefix-and-suffix-pairs-i

Hash Function

3309-count-prefix-and-suffix-pairs-i

Breadth-First Search

1428-jump-game-iii