LeetCode_adprem

Collection of LeetCode questions to ace the coding interview! - Created using LeetHub v3

LeetCode Topics

Array

Problem Name	Difficulty
0015-3sum	Medium
0031-next-permutation	Medium
0033-search-in-rotated-sorted-array	Medium
0035-search-insert-position	Easy
0037-sudoku-solver	Hard
0039-combination-sum	Medium
0042-trapping-rain-water	Hard
0048-rotate-image	Medium
0051-n-queens	Hard
0053-maximum-subarray	Medium
0056-merge-intervals	Medium
0057-insert-interval	Medium
0063-unique-paths-ii	Medium
0064-minimum-path-sum	Medium
0075-sort-colors	Medium
0079-word-search	Medium
0081-search-in-rotated-sorted-array-ii	Medium
0084-largest-rectangle-in-histogram	Hard
0088-merge-sorted-array	Easy
0090-subsets-ii	Medium
0105-construct-binary-tree-from-preorder-and-inorder-traversal	Medium
0106-construct-binary-tree-from-inorder-and-postorder-traversal	Medium
0118-pascals-triangle	Easy
0120-triangle	Medium
0121-best-time-to-buy-and-sell-stock	Easy
0130-surrounded-regions	Medium
0154-find-minimum-in-rotated-sorted-array-ii	Hard
0169-majority-element	Easy
0198-house-robber	Medium
0200-number-of-islands	Medium
0216-combination-sum-iii	Medium
0229-majority-element-ii	Medium
0239-sliding-window-maximum	Hard
0287-find-the-duplicate-number	Medium
0322-coin-change	Medium
0350-intersection-of-two-arrays-ii	Easy
0377-combination-sum-iv	Medium
0396-rotate-function	Medium
0416-partition-equal-subset-sum	Medium
0455-assign-cookies	Easy
0493-reverse-pairs	Hard
0494-target-sum	Medium
0495-teemo-attacking	Easy
0496-next-greater-element-i	Easy
0503-next-greater-element-ii	Medium
0518-coin-change-ii	Medium
0540-single-element-in-a-sorted-array	Medium
0542-01-matrix	Medium
0560-subarray-sum-equals-k	Medium
0621-task-scheduler	Medium
0704-binary-search	Easy
0721-accounts-merge	Medium
0733-flood-fill	Easy
0735-asteroid-collision	Medium
0778-swim-in-rising-water	Hard
0827-making-a-large-island	Hard
0846-hand-of-straights	Medium
0907-sum-of-subarray-minimums	Medium
0930-binary-subarrays-with-sum	Medium
0992-subarrays-with-k-different-integers	Hard
0994-rotting-oranges	Medium
1008-construct-binary-search-tree-from-preorder-traversal	Medium
1011-capacity-to-ship-packages-within-d-days	Medium
1091-shortest-path-in-binary-matrix	Medium
1283-find-the-smallest-divisor-given-a-threshold	Medium
1306-jump-game-iii	Medium
1337-the-k-weakest-rows-in-a-matrix	Easy
1340-jump-game-v	Hard
1345-jump-game-iv	Hard
1351-count-negative-numbers-in-a-sorted-matrix	Easy
1391-check-if-there-is-a-valid-path-in-a-grid	Medium
1482-minimum-number-of-days-to-make-m-bouquets	Medium
1536-minimum-swaps-to-arrange-a-binary-grid	Medium
1539-kth-missing-positive-number	Easy
1559-detect-cycles-in-2d-grid	Medium
1605-find-valid-matrix-given-row-and-column-sums	Medium
1631-path-with-minimum-effort	Medium
1656-design-an-ordered-stream	Easy
1665-minimum-initial-energy-to-finish-tasks	Hard
1722-minimize-hamming-distance-after-swap-operations	Medium
1727-largest-submatrix-with-rearrangements	Medium
1752-check-if-array-is-sorted-and-rotated	Easy
1855-maximum-distance-between-a-pair-of-values	Medium
1861-rotating-the-box	Medium
1878-get-biggest-three-rhombus-sums-in-a-grid	Medium
1886-determine-whether-matrix-can-be-obtained-by-rotation	Easy
1914-cyclically-rotating-a-grid	Medium
1980-find-unique-binary-string	Medium
2033-minimum-operations-to-make-a-uni-value-grid	Medium
2078-two-furthest-houses-with-different-colors	Easy
2089-find-target-indices-after-sorting-array	Easy
2104-sum-of-subarray-ranges	Medium
2121-intervals-between-identical-elements	Medium
2126-destroying-asteroids	Medium
2134-minimum-swaps-to-group-all-1s-together-ii	Medium
2144-minimum-cost-of-buying-candies-with-discount	Easy
2149-rearrange-array-elements-by-sign	Medium
2161-partition-array-according-to-given-pivot	Medium
2196-create-binary-tree-from-descriptions	Medium
2410-maximum-matching-of-players-with-trainers	Medium
2446-determine-if-two-events-have-conflict	Easy
2452-words-within-two-edits-of-dictionary	Medium
2515-shortest-distance-to-target-string-in-a-circular-array	Easy
2529-maximum-count-of-positive-integer-and-negative-integer	Easy
2540-minimum-common-value	Easy
2553-separate-the-digits-in-an-array	Easy
2574-left-and-right-sum-differences	Easy
2580-count-ways-to-group-overlapping-ranges	Medium
2615-sum-of-distances	Medium
2657-find-the-prefix-common-array-of-two-arrays	Medium
2751-robot-collisions	Hard
2770-maximum-number-of-jumps-to-reach-the-last-index	Medium
2780-minimum-index-of-a-valid-split	Medium
2784-check-if-array-is-good	Easy
2848-points-that-intersect-with-cars	Easy
2874-maximum-value-of-an-ordered-triplet-ii	Medium
2948-make-lexicographically-smallest-array-by-swapping-elements	Medium
3043-find-the-length-of-the-longest-common-prefix	Medium
3065-minimum-operations-to-exceed-threshold-value-i	Easy
3070-count-submatrices-with-top-left-element-and-sum-less-than-k	Medium
3169-count-days-without-meetings	Medium
3212-count-submatrices-with-equal-frequency-of-x-and-y	Medium
3225-maximum-score-from-grid-operations	Hard
3300-minimum-element-after-replacement-with-digit-sum	Easy
3418-maximum-amount-of-money-robot-can-earn	Medium
3464-maximize-the-distance-between-points-on-a-square	Hard
3629-minimum-jumps-to-reach-end-via-prime-teleportation	Medium
3633-earliest-finish-time-for-land-and-water-rides-i	Easy
3635-earliest-finish-time-for-land-and-water-rides-ii	Medium
3643-flip-square-submatrix-vertically	Easy
3660-jump-game-ix	Medium
3661-maximum-walls-destroyed-by-robots	Hard
3689-maximum-total-subarray-value-i	Medium
3740-minimum-distance-between-three-equal-elements-i	Easy
3742-maximum-path-score-in-a-grid	Medium

Greedy

Problem Name	Difficulty
0402-remove-k-digits	Medium
0455-assign-cookies	Easy
0621-task-scheduler	Medium
0846-hand-of-straights	Medium
1536-minimum-swaps-to-arrange-a-binary-grid	Medium
1605-find-valid-matrix-given-row-and-column-sums	Medium
1665-minimum-initial-energy-to-finish-tasks	Hard
1727-largest-submatrix-with-rearrangements	Medium
2078-two-furthest-houses-with-different-colors	Easy
2116-check-if-a-parentheses-string-can-be-valid	Medium
2126-destroying-asteroids	Medium
2144-minimum-cost-of-buying-candies-with-discount	Easy
2410-maximum-matching-of-players-with-trainers	Medium
3016-minimum-number-of-pushes-to-type-word-ii	Medium
3633-earliest-finish-time-for-land-and-water-rides-i	Easy
3635-earliest-finish-time-for-land-and-water-rides-ii	Medium
3689-maximum-total-subarray-value-i	Medium

Matrix

Problem Name	Difficulty
0037-sudoku-solver	Hard
0048-rotate-image	Medium
0063-unique-paths-ii	Medium
0064-minimum-path-sum	Medium
0079-word-search	Medium
0130-surrounded-regions	Medium
0200-number-of-islands	Medium
0542-01-matrix	Medium
0733-flood-fill	Easy
0778-swim-in-rising-water	Hard
0827-making-a-large-island	Hard
0994-rotting-oranges	Medium
1091-shortest-path-in-binary-matrix	Medium
1337-the-k-weakest-rows-in-a-matrix	Easy
1351-count-negative-numbers-in-a-sorted-matrix	Easy
1391-check-if-there-is-a-valid-path-in-a-grid	Medium
1536-minimum-swaps-to-arrange-a-binary-grid	Medium
1559-detect-cycles-in-2d-grid	Medium
1605-find-valid-matrix-given-row-and-column-sums	Medium
1631-path-with-minimum-effort	Medium
1727-largest-submatrix-with-rearrangements	Medium
1861-rotating-the-box	Medium
1878-get-biggest-three-rhombus-sums-in-a-grid	Medium
1886-determine-whether-matrix-can-be-obtained-by-rotation	Easy
1914-cyclically-rotating-a-grid	Medium
2033-minimum-operations-to-make-a-uni-value-grid	Medium
3070-count-submatrices-with-top-left-element-and-sum-less-than-k	Medium
3212-count-submatrices-with-equal-frequency-of-x-and-y	Medium
3225-maximum-score-from-grid-operations	Hard
3418-maximum-amount-of-money-robot-can-earn	Medium
3643-flip-square-submatrix-vertically	Easy
3742-maximum-path-score-in-a-grid	Medium

String

Problem Name	Difficulty
0017-letter-combinations-of-a-phone-number	Medium
0022-generate-parentheses	Medium
0079-word-search	Medium
0115-distinct-subsequences	Hard
0127-word-ladder	Hard
0402-remove-k-digits	Medium
0424-longest-repeating-character-replacement	Medium
0516-longest-palindromic-subsequence	Medium
0556-next-greater-element-iii	Medium
0721-accounts-merge	Medium
0796-rotate-string	Easy
1092-shortest-common-supersequence	Hard
1143-longest-common-subsequence	Medium
1189-maximum-number-of-balloons	Easy
1415-the-k-th-lexicographical-string-of-all-happy-strings-of-length-n	Medium
1545-find-kth-bit-in-nth-binary-string	Medium
1871-jump-game-vii	Medium
1980-find-unique-binary-string	Medium
2116-check-if-a-parentheses-string-can-be-valid	Medium
2446-determine-if-two-events-have-conflict	Easy
2452-words-within-two-edits-of-dictionary	Medium
2515-shortest-distance-to-target-string-in-a-circular-array	Easy
2833-furthest-point-from-origin	Easy
2840-check-if-strings-can-be-made-equal-with-operations-ii	Medium
3016-minimum-number-of-pushes-to-type-word-ii	Medium
3043-find-the-length-of-the-longest-common-prefix	Medium
3090-maximum-length-substring-with-two-occurrences	Easy
3120-count-the-number-of-special-characters-i	Easy
3121-count-the-number-of-special-characters-ii	Medium

Recursion

Problem Name	Difficulty
0025-reverse-nodes-in-k-group	Hard
0050-powx-n	Medium
0206-reverse-linked-list	Easy
0234-palindrome-linked-list	Easy
1545-find-kth-bit-in-nth-binary-string	Medium
2550-count-collisions-of-monkeys-on-a-polygon	Medium

Simulation

Problem Name	Difficulty
0495-teemo-attacking	Easy
0735-asteroid-collision	Medium
1545-find-kth-bit-in-nth-binary-string	Medium
1914-cyclically-rotating-a-grid	Medium
2149-rearrange-array-elements-by-sign	Medium
2161-partition-array-according-to-given-pivot	Medium
2553-separate-the-digits-in-an-array	Easy
2751-robot-collisions	Hard

Hash Table

Problem Name	Difficulty
0017-letter-combinations-of-a-phone-number	Medium
0037-sudoku-solver	Hard
0105-construct-binary-tree-from-preorder-and-inorder-traversal	Medium
0106-construct-binary-tree-from-inorder-and-postorder-traversal	Medium
0127-word-ladder	Hard
0138-copy-list-with-random-pointer	Medium
0141-linked-list-cycle	Easy
0142-linked-list-cycle-ii	Medium
0146-lru-cache	Medium
0160-intersection-of-two-linked-lists	Easy
0169-majority-element	Easy
0229-majority-element-ii	Medium
0350-intersection-of-two-arrays-ii	Easy
0424-longest-repeating-character-replacement	Medium
0460-lfu-cache	Hard
0496-next-greater-element-i	Easy
0560-subarray-sum-equals-k	Medium
0621-task-scheduler	Medium
0653-two-sum-iv-input-is-a-bst	Easy
0721-accounts-merge	Medium
0846-hand-of-straights	Medium
0863-all-nodes-distance-k-in-binary-tree	Medium
0930-binary-subarrays-with-sum	Medium
0947-most-stones-removed-with-same-row-or-column	Medium
0987-vertical-order-traversal-of-a-binary-tree	Hard
0992-subarrays-with-k-different-integers	Hard
1189-maximum-number-of-balloons	Easy
1345-jump-game-iv	Hard
1656-design-an-ordered-stream	Easy
1980-find-unique-binary-string	Medium
2121-intervals-between-identical-elements	Medium
2196-create-binary-tree-from-descriptions	Medium
2540-minimum-common-value	Easy
2615-sum-of-distances	Medium
2657-find-the-prefix-common-array-of-two-arrays	Medium
2780-minimum-index-of-a-valid-split	Medium
2784-check-if-array-is-good	Easy
2840-check-if-strings-can-be-made-equal-with-operations-ii	Medium
2848-points-that-intersect-with-cars	Easy
3016-minimum-number-of-pushes-to-type-word-ii	Medium
3043-find-the-length-of-the-longest-common-prefix	Medium
3090-maximum-length-substring-with-two-occurrences	Easy
3120-count-the-number-of-special-characters-i	Easy
3121-count-the-number-of-special-characters-ii	Medium
3629-minimum-jumps-to-reach-end-via-prime-teleportation	Medium
3740-minimum-distance-between-three-equal-elements-i	Easy

Backtracking

Problem Name	Difficulty
0017-letter-combinations-of-a-phone-number	Medium
0022-generate-parentheses	Medium
0037-sudoku-solver	Hard
0039-combination-sum	Medium
0051-n-queens	Hard
0079-word-search	Medium
0090-subsets-ii	Medium
0113-path-sum-ii	Medium
0216-combination-sum-iii	Medium
0494-target-sum	Medium
1415-the-k-th-lexicographical-string-of-all-happy-strings-of-length-n	Medium
1980-find-unique-binary-string	Medium

Bit Manipulation

Problem Name	Difficulty
0090-subsets-ii	Medium
0222-count-complete-tree-nodes	Medium
0287-find-the-duplicate-number	Medium
1009-complement-of-base-10-integer	Easy
2657-find-the-prefix-common-array-of-two-arrays	Medium

Binary Search

Problem Name	Difficulty
0033-search-in-rotated-sorted-array	Medium
0035-search-insert-position	Easy
0081-search-in-rotated-sorted-array-ii	Medium
0154-find-minimum-in-rotated-sorted-array-ii	Hard
0222-count-complete-tree-nodes	Medium
0287-find-the-duplicate-number	Medium
0350-intersection-of-two-arrays-ii	Easy
0493-reverse-pairs	Hard
0540-single-element-in-a-sorted-array	Medium
0704-binary-search	Easy
0778-swim-in-rising-water	Hard
1011-capacity-to-ship-packages-within-d-days	Medium
1237-find-positive-integer-solution-for-a-given-equation	Medium
1283-find-the-smallest-divisor-given-a-threshold	Medium
1337-the-k-weakest-rows-in-a-matrix	Easy
1351-count-negative-numbers-in-a-sorted-matrix	Easy
1482-minimum-number-of-days-to-make-m-bouquets	Medium
1539-kth-missing-positive-number	Easy
1631-path-with-minimum-effort	Medium
1855-maximum-distance-between-a-pair-of-values	Medium
2089-find-target-indices-after-sorting-array	Easy
2529-maximum-count-of-positive-integer-and-negative-integer	Easy
2540-minimum-common-value	Easy
3464-maximize-the-distance-between-points-on-a-square	Hard
3633-earliest-finish-time-for-land-and-water-rides-i	Easy
3635-earliest-finish-time-for-land-and-water-rides-ii	Medium
3661-maximum-walls-destroyed-by-robots	Hard

Sorting

Problem Name	Difficulty
0015-3sum	Medium
0056-merge-intervals	Medium
0075-sort-colors	Medium
0088-merge-sorted-array	Easy
0148-sort-list	Medium
0169-majority-element	Easy
0229-majority-element-ii	Medium
0350-intersection-of-two-arrays-ii	Easy
0455-assign-cookies	Easy
0621-task-scheduler	Medium
0721-accounts-merge	Medium
0846-hand-of-straights	Medium
0987-vertical-order-traversal-of-a-binary-tree	Hard
1337-the-k-weakest-rows-in-a-matrix	Easy
1340-jump-game-v	Hard
1665-minimum-initial-energy-to-finish-tasks	Hard
1727-largest-submatrix-with-rearrangements	Medium
1878-get-biggest-three-rhombus-sums-in-a-grid	Medium
2033-minimum-operations-to-make-a-uni-value-grid	Medium
2089-find-target-indices-after-sorting-array	Easy
2126-destroying-asteroids	Medium
2144-minimum-cost-of-buying-candies-with-discount	Easy
2410-maximum-matching-of-players-with-trainers	Medium
2580-count-ways-to-group-overlapping-ranges	Medium
2751-robot-collisions	Hard
2780-minimum-index-of-a-valid-split	Medium
2784-check-if-array-is-good	Easy
2840-check-if-strings-can-be-made-equal-with-operations-ii	Medium
2948-make-lexicographically-smallest-array-by-swapping-elements	Medium
3016-minimum-number-of-pushes-to-type-word-ii	Medium
3169-count-days-without-meetings	Medium
3464-maximize-the-distance-between-points-on-a-square	Hard
3633-earliest-finish-time-for-land-and-water-rides-i	Easy
3635-earliest-finish-time-for-land-and-water-rides-ii	Medium
3661-maximum-walls-destroyed-by-robots	Hard

Counting

Problem Name	Difficulty
0169-majority-element	Easy
0229-majority-element-ii	Medium
0621-task-scheduler	Medium
0992-subarrays-with-k-different-integers	Hard
1189-maximum-number-of-balloons	Easy
2529-maximum-count-of-positive-integer-and-negative-integer	Easy
2833-furthest-point-from-origin	Easy
3016-minimum-number-of-pushes-to-type-word-ii	Medium

Math

Problem Name	Difficulty
0007-reverse-integer	Medium
0048-rotate-image	Medium
0050-powx-n	Medium
0062-unique-paths	Medium
0372-super-pow	Medium
0396-rotate-function	Medium
0556-next-greater-element-iii	Medium
0788-rotated-digits	Medium
1237-find-positive-integer-solution-for-a-given-equation	Medium
1344-angle-between-hands-of-a-clock	Medium
1878-get-biggest-three-rhombus-sums-in-a-grid	Medium
2033-minimum-operations-to-make-a-uni-value-grid	Medium
2550-count-collisions-of-monkeys-on-a-polygon	Medium
3300-minimum-element-after-replacement-with-digit-sum	Easy
3464-maximize-the-distance-between-points-on-a-square	Hard
3558-number-of-ways-to-assign-edge-weights-i	Medium
3629-minimum-jumps-to-reach-end-via-prime-teleportation	Medium
3751-total-waviness-of-numbers-in-range-i	Medium
3753-total-waviness-of-numbers-in-range-ii	Hard

Heap (Priority Queue)

Problem Name	Difficulty
0023-merge-k-sorted-lists	Hard
0239-sliding-window-maximum	Hard
0621-task-scheduler	Medium
0743-network-delay-time	Medium
0778-swim-in-rising-water	Hard
0787-cheapest-flights-within-k-stops	Medium
1337-the-k-weakest-rows-in-a-matrix	Easy
1631-path-with-minimum-effort	Medium
1878-get-biggest-three-rhombus-sums-in-a-grid	Medium

Prefix Sum

Problem Name	Difficulty
0560-subarray-sum-equals-k	Medium
0930-binary-subarrays-with-sum	Medium
1871-jump-game-vii	Medium
1878-get-biggest-three-rhombus-sums-in-a-grid	Medium
2121-intervals-between-identical-elements	Medium
2574-left-and-right-sum-differences	Easy
2615-sum-of-distances	Medium
2848-points-that-intersect-with-cars	Easy
2874-maximum-value-of-an-ordered-triplet-ii	Medium
3070-count-submatrices-with-top-left-element-and-sum-less-than-k	Medium
3212-count-submatrices-with-equal-frequency-of-x-and-y	Medium
3225-maximum-score-from-grid-operations	Hard

Two Pointers

Problem Name	Difficulty
0015-3sum	Medium
0019-remove-nth-node-from-end-of-list	Medium
0031-next-permutation	Medium
0042-trapping-rain-water	Hard
0061-rotate-list	Medium
0075-sort-colors	Medium
0088-merge-sorted-array	Easy
0141-linked-list-cycle	Easy
0142-linked-list-cycle-ii	Medium
0148-sort-list	Medium
0160-intersection-of-two-linked-lists	Easy
0234-palindrome-linked-list	Easy
0287-find-the-duplicate-number	Medium
0350-intersection-of-two-arrays-ii	Easy
0455-assign-cookies	Easy
0556-next-greater-element-iii	Medium
0653-two-sum-iv-input-is-a-bst	Easy
0876-middle-of-the-linked-list	Easy
1237-find-positive-integer-solution-for-a-given-equation	Medium
1855-maximum-distance-between-a-pair-of-values	Medium
1861-rotating-the-box	Medium
2095-delete-the-middle-node-of-a-linked-list	Medium
2149-rearrange-array-elements-by-sign	Medium
2161-partition-array-according-to-given-pivot	Medium
2410-maximum-matching-of-players-with-trainers	Medium
2540-minimum-common-value	Easy
3633-earliest-finish-time-for-land-and-water-rides-i	Easy
3635-earliest-finish-time-for-land-and-water-rides-ii	Medium
3643-flip-square-submatrix-vertically	Easy

Interactive

Problem Name	Difficulty
1237-find-positive-integer-solution-for-a-given-equation	Medium

Linked List

Problem Name	Difficulty
0019-remove-nth-node-from-end-of-list	Medium
0023-merge-k-sorted-lists	Hard
0025-reverse-nodes-in-k-group	Hard
0061-rotate-list	Medium
0083-remove-duplicates-from-sorted-list	Easy
0114-flatten-binary-tree-to-linked-list	Medium
0138-copy-list-with-random-pointer	Medium
0141-linked-list-cycle	Easy
0142-linked-list-cycle-ii	Medium
0146-lru-cache	Medium
0148-sort-list	Medium
0160-intersection-of-two-linked-lists	Easy
0206-reverse-linked-list	Easy
0234-palindrome-linked-list	Easy
0237-delete-node-in-a-linked-list	Medium
0328-odd-even-linked-list	Medium
0460-lfu-cache	Hard
0725-split-linked-list-in-parts	Medium
0876-middle-of-the-linked-list	Easy
2095-delete-the-middle-node-of-a-linked-list	Medium

Design

Problem Name	Difficulty
0146-lru-cache	Medium
0155-min-stack	Medium
0173-binary-search-tree-iterator	Medium
0460-lfu-cache	Hard
0901-online-stock-span	Medium
1656-design-an-ordered-stream	Easy

Data Stream

Problem Name	Difficulty
0901-online-stock-span	Medium
1656-design-an-ordered-stream	Easy

Sliding Window

Problem Name	Difficulty
0239-sliding-window-maximum	Hard
0424-longest-repeating-character-replacement	Medium
0930-binary-subarrays-with-sum	Medium
0992-subarrays-with-k-different-integers	Hard
1871-jump-game-vii	Medium
2134-minimum-swaps-to-group-all-1s-together-ii	Medium
3090-maximum-length-substring-with-two-occurrences	Easy

Stack

Problem Name	Difficulty
0042-trapping-rain-water	Hard
0084-largest-rectangle-in-histogram	Hard
0114-flatten-binary-tree-to-linked-list	Medium
0155-min-stack	Medium
0173-binary-search-tree-iterator	Medium
0234-palindrome-linked-list	Easy
0402-remove-k-digits	Medium
0496-next-greater-element-i	Easy
0503-next-greater-element-ii	Medium
0735-asteroid-collision	Medium
0901-online-stock-span	Medium
0907-sum-of-subarray-minimums	Medium
1008-construct-binary-search-tree-from-preorder-traversal	Medium
2104-sum-of-subarray-ranges	Medium
2116-check-if-a-parentheses-string-can-be-valid	Medium
2751-robot-collisions	Hard

Dynamic Programming

Problem Name	Difficulty
0022-generate-parentheses	Medium
0042-trapping-rain-water	Hard
0053-maximum-subarray	Medium
0062-unique-paths	Medium
0063-unique-paths-ii	Medium
0064-minimum-path-sum	Medium
0115-distinct-subsequences	Hard
0118-pascals-triangle	Easy
0120-triangle	Medium
0121-best-time-to-buy-and-sell-stock	Easy
0124-binary-tree-maximum-path-sum	Hard
0198-house-robber	Medium
0322-coin-change	Medium
0377-combination-sum-iv	Medium
0396-rotate-function	Medium
0416-partition-equal-subset-sum	Medium
0494-target-sum	Medium
0516-longest-palindromic-subsequence	Medium
0518-coin-change-ii	Medium
0542-01-matrix	Medium
0787-cheapest-flights-within-k-stops	Medium
0788-rotated-digits	Medium
0907-sum-of-subarray-minimums	Medium
1092-shortest-common-supersequence	Hard
1143-longest-common-subsequence	Medium
1340-jump-game-v	Hard
1871-jump-game-vii	Medium
1976-number-of-ways-to-arrive-at-destination	Medium
2770-maximum-number-of-jumps-to-reach-the-last-index	Medium
3225-maximum-score-from-grid-operations	Hard
3418-maximum-amount-of-money-robot-can-earn	Medium
3660-jump-game-ix	Medium
3661-maximum-walls-destroyed-by-robots	Hard
3742-maximum-path-score-in-a-grid	Medium
3751-total-waviness-of-numbers-in-range-i	Medium
3753-total-waviness-of-numbers-in-range-ii	Hard

Database

Problem Name	Difficulty
0175-combine-two-tables	Easy
0181-employees-earning-more-than-their-managers	Easy
0182-duplicate-emails	Easy
0183-customers-who-never-order	Easy
0196-delete-duplicate-emails	Easy
0511-game-play-analysis-i	Easy
0584-find-customer-referee	Easy
0595-big-countries	Easy
1148-article-views-i	Easy
1581-customer-who-visited-but-did-not-make-any-transactions	Easy
1661-average-time-of-process-per-machine	Easy
1757-recyclable-and-low-fat-products	Easy
2356-number-of-unique-subjects-taught-by-each-teacher	Easy

Trie

Problem Name	Difficulty
2452-words-within-two-edits-of-dictionary	Medium
3043-find-the-length-of-the-longest-common-prefix	Medium

Depth-First Search

Problem Name	Difficulty
0079-word-search	Medium
0099-recover-binary-search-tree	Medium
0100-same-tree	Easy
0101-symmetric-tree	Easy
0104-maximum-depth-of-binary-tree	Easy
0110-balanced-binary-tree	Easy
0113-path-sum-ii	Medium
0114-flatten-binary-tree-to-linked-list	Medium
0124-binary-tree-maximum-path-sum	Hard
0130-surrounded-regions	Medium
0200-number-of-islands	Medium
0207-course-schedule	Medium
0210-course-schedule-ii	Medium
0230-kth-smallest-element-in-a-bst	Medium
0235-lowest-common-ancestor-of-a-binary-search-tree	Medium
0236-lowest-common-ancestor-of-a-binary-tree	Medium
0515-find-largest-value-in-each-tree-row	Medium
0543-diameter-of-binary-tree	Easy
0547-number-of-provinces	Medium
0653-two-sum-iv-input-is-a-bst	Easy
0662-maximum-width-of-binary-tree	Medium
0721-accounts-merge	Medium
0733-flood-fill	Easy
0743-network-delay-time	Medium
0778-swim-in-rising-water	Hard
0785-is-graph-bipartite	Medium
0787-cheapest-flights-within-k-stops	Medium
0802-find-eventual-safe-states	Medium
0827-making-a-large-island	Hard
0863-all-nodes-distance-k-in-binary-tree	Medium
0947-most-stones-removed-with-same-row-or-column	Medium
0987-vertical-order-traversal-of-a-binary-tree	Hard
1192-critical-connections-in-a-network	Hard
1306-jump-game-iii	Medium
1315-sum-of-nodes-with-even-valued-grandparent	Medium
1319-number-of-operations-to-make-network-connected	Medium
1391-check-if-there-is-a-valid-path-in-a-grid	Medium
1559-detect-cycles-in-2d-grid	Medium
1631-path-with-minimum-effort	Medium
1722-minimize-hamming-distance-after-swap-operations	Medium
3558-number-of-ways-to-assign-edge-weights-i	Medium

Union-Find

Problem Name	Difficulty
0130-surrounded-regions	Medium
0200-number-of-islands	Medium
0547-number-of-provinces	Medium
0721-accounts-merge	Medium
0778-swim-in-rising-water	Hard
0785-is-graph-bipartite	Medium
0827-making-a-large-island	Hard
0947-most-stones-removed-with-same-row-or-column	Medium
1319-number-of-operations-to-make-network-connected	Medium
1391-check-if-there-is-a-valid-path-in-a-grid	Medium
1559-detect-cycles-in-2d-grid	Medium
1631-path-with-minimum-effort	Medium
1722-minimize-hamming-distance-after-swap-operations	Medium
2948-make-lexicographically-smallest-array-by-swapping-elements	Medium

Geometry

Problem Name	Difficulty
3464-maximize-the-distance-between-points-on-a-square	Hard

Breadth-First Search

Problem Name	Difficulty
0100-same-tree	Easy
0101-symmetric-tree	Easy
0103-binary-tree-zigzag-level-order-traversal	Medium
0104-maximum-depth-of-binary-tree	Easy
0127-word-ladder	Hard
0130-surrounded-regions	Medium
0200-number-of-islands	Medium
0207-course-schedule	Medium
0210-course-schedule-ii	Medium
0322-coin-change	Medium
0515-find-largest-value-in-each-tree-row	Medium
0542-01-matrix	Medium
0547-number-of-provinces	Medium
0653-two-sum-iv-input-is-a-bst	Easy
0662-maximum-width-of-binary-tree	Medium
0721-accounts-merge	Medium
0733-flood-fill	Easy
0743-network-delay-time	Medium
0778-swim-in-rising-water	Hard
0785-is-graph-bipartite	Medium
0787-cheapest-flights-within-k-stops	Medium
0802-find-eventual-safe-states	Medium
0827-making-a-large-island	Hard
0863-all-nodes-distance-k-in-binary-tree	Medium
0987-vertical-order-traversal-of-a-binary-tree	Hard
0994-rotting-oranges	Medium
1091-shortest-path-in-binary-matrix	Medium
1306-jump-game-iii	Medium
1315-sum-of-nodes-with-even-valued-grandparent	Medium
1319-number-of-operations-to-make-network-connected	Medium
1345-jump-game-iv	Hard
1391-check-if-there-is-a-valid-path-in-a-grid	Medium
1559-detect-cycles-in-2d-grid	Medium
1631-path-with-minimum-effort	Medium
3629-minimum-jumps-to-reach-end-via-prime-teleportation	Medium

Graph Theory

Problem Name	Difficulty
0207-course-schedule	Medium
0210-course-schedule-ii	Medium
0547-number-of-provinces	Medium
0743-network-delay-time	Medium
0785-is-graph-bipartite	Medium
0787-cheapest-flights-within-k-stops	Medium
0802-find-eventual-safe-states	Medium
0947-most-stones-removed-with-same-row-or-column	Medium
1192-critical-connections-in-a-network	Hard
1319-number-of-operations-to-make-network-connected	Medium
1976-number-of-ways-to-arrive-at-destination	Medium

Divide and Conquer

Problem Name	Difficulty
0023-merge-k-sorted-lists	Hard
0053-maximum-subarray	Medium
0105-construct-binary-tree-from-preorder-and-inorder-traversal	Medium
0106-construct-binary-tree-from-inorder-and-postorder-traversal	Medium
0148-sort-list	Medium
0169-majority-element	Easy
0372-super-pow	Medium
0493-reverse-pairs	Hard

String Matching

Problem Name	Difficulty
0796-rotate-string	Easy

Number Theory

Problem Name	Difficulty
3629-minimum-jumps-to-reach-end-via-prime-teleportation	Medium

Enumeration

Problem Name	Difficulty
3751-total-waviness-of-numbers-in-range-i	Medium

Tree

Problem Name	Difficulty
0099-recover-binary-search-tree	Medium
0100-same-tree	Easy
0101-symmetric-tree	Easy
0103-binary-tree-zigzag-level-order-traversal	Medium
0104-maximum-depth-of-binary-tree	Easy
0105-construct-binary-tree-from-preorder-and-inorder-traversal	Medium
0106-construct-binary-tree-from-inorder-and-postorder-traversal	Medium
0110-balanced-binary-tree	Easy
0113-path-sum-ii	Medium
0114-flatten-binary-tree-to-linked-list	Medium
0124-binary-tree-maximum-path-sum	Hard
0173-binary-search-tree-iterator	Medium
0222-count-complete-tree-nodes	Medium
0230-kth-smallest-element-in-a-bst	Medium
0235-lowest-common-ancestor-of-a-binary-search-tree	Medium
0236-lowest-common-ancestor-of-a-binary-tree	Medium
0450-delete-node-in-a-bst	Medium
0515-find-largest-value-in-each-tree-row	Medium
0543-diameter-of-binary-tree	Easy
0653-two-sum-iv-input-is-a-bst	Easy
0662-maximum-width-of-binary-tree	Medium
0700-search-in-a-binary-search-tree	Easy
0701-insert-into-a-binary-search-tree	Medium
0863-all-nodes-distance-k-in-binary-tree	Medium
0987-vertical-order-traversal-of-a-binary-tree	Hard
1008-construct-binary-search-tree-from-preorder-traversal	Medium
1315-sum-of-nodes-with-even-valued-grandparent	Medium
2196-create-binary-tree-from-descriptions	Medium
3558-number-of-ways-to-assign-edge-weights-i	Medium

Binary Tree

Problem Name	Difficulty
0099-recover-binary-search-tree	Medium
0100-same-tree	Easy
0101-symmetric-tree	Easy
0103-binary-tree-zigzag-level-order-traversal	Medium
0104-maximum-depth-of-binary-tree	Easy
0105-construct-binary-tree-from-preorder-and-inorder-traversal	Medium
0106-construct-binary-tree-from-inorder-and-postorder-traversal	Medium
0110-balanced-binary-tree	Easy
0113-path-sum-ii	Medium
0114-flatten-binary-tree-to-linked-list	Medium
0124-binary-tree-maximum-path-sum	Hard
0173-binary-search-tree-iterator	Medium
0222-count-complete-tree-nodes	Medium
0230-kth-smallest-element-in-a-bst	Medium
0235-lowest-common-ancestor-of-a-binary-search-tree	Medium
0236-lowest-common-ancestor-of-a-binary-tree	Medium
0450-delete-node-in-a-bst	Medium
0515-find-largest-value-in-each-tree-row	Medium
0543-diameter-of-binary-tree	Easy
0653-two-sum-iv-input-is-a-bst	Easy
0662-maximum-width-of-binary-tree	Medium
0700-search-in-a-binary-search-tree	Easy
0701-insert-into-a-binary-search-tree	Medium
0863-all-nodes-distance-k-in-binary-tree	Medium
0987-vertical-order-traversal-of-a-binary-tree	Hard
1008-construct-binary-search-tree-from-preorder-traversal	Medium
1315-sum-of-nodes-with-even-valued-grandparent	Medium
2196-create-binary-tree-from-descriptions	Medium

Binary Indexed Tree

Problem Name	Difficulty
0493-reverse-pairs	Hard

Segment Tree

Problem Name	Difficulty
0493-reverse-pairs	Hard

Merge Sort

Problem Name	Difficulty
0023-merge-k-sorted-lists	Hard
0148-sort-list	Medium
0493-reverse-pairs	Hard

Ordered Set

Problem Name	Difficulty
0493-reverse-pairs	Hard

Combinatorics

Problem Name	Difficulty
0062-unique-paths	Medium

Monotonic Stack

Problem Name	Difficulty
0042-trapping-rain-water	Hard
0084-largest-rectangle-in-histogram	Hard
0402-remove-k-digits	Medium
0496-next-greater-element-i	Easy
0503-next-greater-element-ii	Medium
0901-online-stock-span	Medium
0907-sum-of-subarray-minimums	Medium
1008-construct-binary-search-tree-from-preorder-traversal	Medium
2104-sum-of-subarray-ranges	Medium

Topological Sort

Problem Name	Difficulty
0207-course-schedule	Medium
0210-course-schedule-ii	Medium
0802-find-eventual-safe-states	Medium
1976-number-of-ways-to-arrive-at-destination	Medium

Directed Acyclic Graph

Problem Name	Difficulty
0207-course-schedule	Medium

Bidirectional Search

Problem Name	Difficulty
0127-word-ladder	Hard

Graph Coloring

Problem Name	Difficulty
0785-is-graph-bipartite	Medium

Bipartite Graph

Problem Name	Difficulty
0785-is-graph-bipartite	Medium
0947-most-stones-removed-with-same-row-or-column	Medium

Kosaraju's Algorithm

Problem Name	Difficulty
0802-find-eventual-safe-states	Medium

Tarjan's SCC Algorithm

Problem Name	Difficulty
0802-find-eventual-safe-states	Medium

Dijkstra's Algorithm

Problem Name	Difficulty
0743-network-delay-time	Medium
1631-path-with-minimum-effort	Medium
1976-number-of-ways-to-arrive-at-destination	Medium

Shortest Path

Problem Name	Difficulty
0743-network-delay-time	Medium
0787-cheapest-flights-within-k-stops	Medium
1976-number-of-ways-to-arrive-at-destination	Medium

Range Minimum/Maximum Query

Problem Name	Difficulty
0084-largest-rectangle-in-histogram	Hard
0239-sliding-window-maximum	Hard

Quicksort

Problem Name	Difficulty
0056-merge-intervals	Medium
0075-sort-colors	Medium
0455-assign-cookies	Easy

Bubble Sort

Problem Name	Difficulty
0075-sort-colors	Medium

Queue

Problem Name	Difficulty
0239-sliding-window-maximum	Hard

Monotonic Queue

Problem Name	Difficulty
0239-sliding-window-maximum	Hard

Floyd's Cycle Finding Algorithm

Problem Name	Difficulty
0141-linked-list-cycle	Easy
0142-linked-list-cycle-ii	Medium

DP on Trees

Problem Name	Difficulty
0124-binary-tree-maximum-path-sum	Hard
0543-diameter-of-binary-tree	Easy

Binary Lifting

Problem Name	Difficulty
0235-lowest-common-ancestor-of-a-binary-search-tree	Medium
0236-lowest-common-ancestor-of-a-binary-tree	Medium

Lowest Common Ancestor

Problem Name	Difficulty
0235-lowest-common-ancestor-of-a-binary-search-tree	Medium
0236-lowest-common-ancestor-of-a-binary-tree	Medium

Binary Search Tree

Problem Name	Difficulty
0099-recover-binary-search-tree	Medium
0173-binary-search-tree-iterator	Medium
0230-kth-smallest-element-in-a-bst	Medium
0235-lowest-common-ancestor-of-a-binary-search-tree	Medium
0450-delete-node-in-a-bst	Medium
0653-two-sum-iv-input-is-a-bst	Easy
0700-search-in-a-binary-search-tree	Easy
0701-insert-into-a-binary-search-tree	Medium
1008-construct-binary-search-tree-from-preorder-traversal	Medium

Iterator

Problem Name	Difficulty
0173-binary-search-tree-iterator	Medium

Boyer–Moore Majority Vote Algorithm

Problem Name	Difficulty
0229-majority-element-ii	Medium

Knapsack Problem

Problem Name	Difficulty
0322-coin-change	Medium
0416-partition-equal-subset-sum	Medium
0494-target-sum	Medium

0-1 Knapsack

Problem Name	Difficulty
0416-partition-equal-subset-sum	Medium
0494-target-sum	Medium

Complete Knapsack

Problem Name	Difficulty
0322-coin-change	Medium

Longest Common Subsequence

Problem Name	Difficulty
1092-shortest-common-supersequence	Hard
1143-longest-common-subsequence	Medium

Doubly-Linked List

Problem Name	Difficulty
0146-lru-cache	Medium
0460-lfu-cache	Hard

Tournament Sort

Problem Name	Difficulty
0023-merge-k-sorted-lists	Hard

Biconnected Component

Problem Name	Difficulty
1192-critical-connections-in-a-network	Hard

Bridge (Graph)

Problem Name	Difficulty
1192-critical-connections-in-a-network	Hard