leetcodeSolution

LeetCode Topics

Array

0004-median-of-two-sorted-arrays
0014-longest-common-prefix
0027-remove-element
0031-next-permutation
0033-search-in-rotated-sorted-array
0036-valid-sudoku
0039-combination-sum
0042-trapping-rain-water
0045-jump-game-ii
0046-permutations
0048-rotate-image
0049-group-anagrams
0053-maximum-subarray
0054-spiral-matrix
0055-jump-game
0057-insert-interval
0063-unique-paths-ii
0064-minimum-path-sum
0068-text-justification
0073-set-matrix-zeroes
0079-word-search
0088-merge-sorted-array
0105-construct-binary-tree-from-preorder-and-inorder-traversal
0106-construct-binary-tree-from-inorder-and-postorder-traversal
0108-convert-sorted-array-to-binary-search-tree
0120-triangle
0122-best-time-to-buy-and-sell-stock-ii
0128-longest-consecutive-sequence
0130-surrounded-regions
0134-gas-station
0135-candy
0137-single-number-ii
0139-word-break
0149-max-points-on-a-line
0150-evaluate-reverse-polish-notation
0153-find-minimum-in-rotated-sorted-array
0188-best-time-to-buy-and-sell-stock-iv
0189-rotate-array
0198-house-robber
0200-number-of-islands
0212-word-search-ii
0215-kth-largest-element-in-an-array
0216-combination-sum-iii
0219-contains-duplicate-ii
0228-summary-ranges
0274-h-index
0289-game-of-life
0300-longest-increasing-subsequence
0322-coin-change
0373-find-k-pairs-with-smallest-sums
0399-evaluate-division
0427-construct-quad-tree
0435-non-overlapping-intervals
0452-minimum-number-of-arrows-to-burst-balloons
0502-ipo
0714-best-time-to-buy-and-sell-stock-with-transaction-fee
0739-daily-temperatures
0875-koko-eating-bananas
0909-snakes-and-ladders
0918-maximum-sum-circular-subarray
0994-rotting-oranges
1207-unique-number-of-occurrences
1268-search-suggestions-system
1926-nearest-exit-from-entrance-in-maze
2300-successful-pairs-of-spells-and-potions
2352-equal-row-and-column-pairs
2462-total-cost-to-hire-k-workers
2542-maximum-subsequence-score

Two Pointers

0027-remove-element
0028-find-the-index-of-the-first-occurrence-in-a-string
0031-next-permutation
0042-trapping-rain-water
0061-rotate-list
0082-remove-duplicates-from-sorted-list-ii
0086-partition-list
0088-merge-sorted-array
0141-linked-list-cycle
0148-sort-list
0189-rotate-array
0295-find-median-from-data-stream
2095-delete-the-middle-node-of-a-linked-list
2130-maximum-twin-sum-of-a-linked-list
2300-successful-pairs-of-spells-and-potions
2462-total-cost-to-hire-k-workers

Sorting

0049-group-anagrams
0088-merge-sorted-array
0148-sort-list
0215-kth-largest-element-in-an-array
0242-valid-anagram
0274-h-index
0295-find-median-from-data-stream
0389-find-the-difference
0435-non-overlapping-intervals
0452-minimum-number-of-arrows-to-burst-balloons
0502-ipo
1268-search-suggestions-system
1657-determine-if-two-strings-are-close
2300-successful-pairs-of-spells-and-potions
2542-maximum-subsequence-score

Hash Table

0012-integer-to-roman
0013-roman-to-integer
0017-letter-combinations-of-a-phone-number
0036-valid-sudoku
0049-group-anagrams
0073-set-matrix-zeroes
0105-construct-binary-tree-from-preorder-and-inorder-traversal
0106-construct-binary-tree-from-inorder-and-postorder-traversal
0127-word-ladder
0128-longest-consecutive-sequence
0133-clone-graph
0138-copy-list-with-random-pointer
0139-word-break
0141-linked-list-cycle
0149-max-points-on-a-line
0205-isomorphic-strings
0208-implement-trie-prefix-tree
0219-contains-duplicate-ii
0242-valid-anagram
0290-word-pattern
0383-ransom-note
0389-find-the-difference
0433-minimum-genetic-mutation
1207-unique-number-of-occurrences
1657-determine-if-two-strings-are-close
2336-smallest-number-in-infinite-set
2352-equal-row-and-column-pairs

String

0006-zigzag-conversion
0012-integer-to-roman
0013-roman-to-integer
0014-longest-common-prefix
0017-letter-combinations-of-a-phone-number
0022-generate-parentheses
0028-find-the-index-of-the-first-occurrence-in-a-string
0049-group-anagrams
0058-length-of-last-word
0068-text-justification
0072-edit-distance
0079-word-search
0097-interleaving-string
0127-word-ladder
0139-word-break
0205-isomorphic-strings
0208-implement-trie-prefix-tree
0211-design-add-and-search-words-data-structure
0212-word-search-ii
0224-basic-calculator
0242-valid-anagram
0290-word-pattern
0383-ransom-note
0389-find-the-difference
0399-evaluate-division
0433-minimum-genetic-mutation
0649-dota2-senate
1143-longest-common-subsequence
1268-search-suggestions-system
1657-determine-if-two-strings-are-close

Bit Manipulation

0137-single-number-ii
0190-reverse-bits
0191-number-of-1-bits
0201-bitwise-and-of-numbers-range
0222-count-complete-tree-nodes
0389-find-the-difference

Linked List

0002-add-two-numbers
0023-merge-k-sorted-lists
0025-reverse-nodes-in-k-group
0061-rotate-list
0082-remove-duplicates-from-sorted-list-ii
0086-partition-list
0092-reverse-linked-list-ii
0114-flatten-binary-tree-to-linked-list
0117-populating-next-right-pointers-in-each-node-ii
0138-copy-list-with-random-pointer
0141-linked-list-cycle
0148-sort-list
0328-odd-even-linked-list
2095-delete-the-middle-node-of-a-linked-list
2130-maximum-twin-sum-of-a-linked-list

Math

0002-add-two-numbers
0012-integer-to-roman
0013-roman-to-integer
0048-rotate-image
0050-powx-n
0062-unique-paths
0070-climbing-stairs
0149-max-points-on-a-line
0150-evaluate-reverse-polish-notation
0172-factorial-trailing-zeroes
0189-rotate-array
0224-basic-calculator

Recursion

0002-add-two-numbers
0025-reverse-nodes-in-k-group
0050-powx-n
0224-basic-calculator

Design

0155-min-stack
0173-binary-search-tree-iterator
0208-implement-trie-prefix-tree
0211-design-add-and-search-words-data-structure
0295-find-median-from-data-stream
2336-smallest-number-in-infinite-set

Trie

0014-longest-common-prefix
0139-word-break
0208-implement-trie-prefix-tree
0211-design-add-and-search-words-data-structure
0212-word-search-ii
1268-search-suggestions-system

Dynamic Programming

0022-generate-parentheses
0042-trapping-rain-water
0045-jump-game-ii
0053-maximum-subarray
0055-jump-game
0062-unique-paths
0063-unique-paths-ii
0064-minimum-path-sum
0070-climbing-stairs
0072-edit-distance
0097-interleaving-string
0120-triangle
0122-best-time-to-buy-and-sell-stock-ii
0139-word-break
0188-best-time-to-buy-and-sell-stock-iv
0198-house-robber
0300-longest-increasing-subsequence
0322-coin-change
0435-non-overlapping-intervals
0714-best-time-to-buy-and-sell-stock-with-transaction-fee
0790-domino-and-tromino-tiling
0918-maximum-sum-circular-subarray
1143-longest-common-subsequence
1372-longest-zigzag-path-in-a-binary-tree

Greedy

0045-jump-game-ii
0055-jump-game
0122-best-time-to-buy-and-sell-stock-ii
0134-gas-station
0135-candy
0435-non-overlapping-intervals
0452-minimum-number-of-arrows-to-burst-balloons
0502-ipo
0649-dota2-senate
0714-best-time-to-buy-and-sell-stock-with-transaction-fee
2542-maximum-subsequence-score

Binary Search

0004-median-of-two-sorted-arrays
0033-search-in-rotated-sorted-array
0153-find-minimum-in-rotated-sorted-array
0222-count-complete-tree-nodes
0300-longest-increasing-subsequence
0374-guess-number-higher-or-lower
0875-koko-eating-bananas
1268-search-suggestions-system
2300-successful-pairs-of-spells-and-potions

Heap (Priority Queue)

0023-merge-k-sorted-lists
0215-kth-largest-element-in-an-array
0295-find-median-from-data-stream
0373-find-k-pairs-with-smallest-sums
0502-ipo
1268-search-suggestions-system
2336-smallest-number-in-infinite-set
2462-total-cost-to-hire-k-workers
2542-maximum-subsequence-score

Backtracking

0017-letter-combinations-of-a-phone-number
0022-generate-parentheses
0039-combination-sum
0046-permutations
0052-n-queens-ii
0077-combinations
0079-word-search
0212-word-search-ii
0216-combination-sum-iii

Combinatorics

0062-unique-paths

Matrix

0036-valid-sudoku
0048-rotate-image
0054-spiral-matrix
0063-unique-paths-ii
0064-minimum-path-sum
0073-set-matrix-zeroes
0079-word-search
0130-surrounded-regions
0200-number-of-islands
0212-word-search-ii
0289-game-of-life
0427-construct-quad-tree
0909-snakes-and-ladders
0994-rotting-oranges
1926-nearest-exit-from-entrance-in-maze
2352-equal-row-and-column-pairs

Simulation

0054-spiral-matrix
0068-text-justification
0289-game-of-life
2352-equal-row-and-column-pairs
2462-total-cost-to-hire-k-workers

Counting

0383-ransom-note
1657-determine-if-two-strings-are-close

Stack

0042-trapping-rain-water
0114-flatten-binary-tree-to-linked-list
0150-evaluate-reverse-polish-notation
0155-min-stack
0173-binary-search-tree-iterator
0224-basic-calculator
0739-daily-temperatures
2130-maximum-twin-sum-of-a-linked-list

Monotonic Stack

0042-trapping-rain-water
0739-daily-temperatures

Divide and Conquer

0004-median-of-two-sorted-arrays
0023-merge-k-sorted-lists
0053-maximum-subarray
0105-construct-binary-tree-from-preorder-and-inorder-traversal
0106-construct-binary-tree-from-inorder-and-postorder-traversal
0108-convert-sorted-array-to-binary-search-tree
0148-sort-list
0190-reverse-bits
0191-number-of-1-bits
0215-kth-largest-element-in-an-array
0427-construct-quad-tree
0918-maximum-sum-circular-subarray

Quickselect

0215-kth-largest-element-in-an-array

Ordered Set

2336-smallest-number-in-infinite-set

Depth-First Search

0079-word-search
0098-validate-binary-search-tree
0100-same-tree
0101-symmetric-tree
0104-maximum-depth-of-binary-tree
0112-path-sum
0114-flatten-binary-tree-to-linked-list
0117-populating-next-right-pointers-in-each-node-ii
0129-sum-root-to-leaf-numbers
0130-surrounded-regions
0133-clone-graph
0199-binary-tree-right-side-view
0200-number-of-islands
0207-course-schedule
0210-course-schedule-ii
0211-design-add-and-search-words-data-structure
0230-kth-smallest-element-in-a-bst
0236-lowest-common-ancestor-of-a-binary-tree
0399-evaluate-division
0437-path-sum-iii
0530-minimum-absolute-difference-in-bst
0547-number-of-provinces
0637-average-of-levels-in-binary-tree
0841-keys-and-rooms
0872-leaf-similar-trees
1161-maximum-level-sum-of-a-binary-tree
1372-longest-zigzag-path-in-a-binary-tree
1448-count-good-nodes-in-binary-tree
1466-reorder-routes-to-make-all-paths-lead-to-the-city-zero

Breadth-First Search

0100-same-tree
0101-symmetric-tree
0102-binary-tree-level-order-traversal
0103-binary-tree-zigzag-level-order-traversal
0104-maximum-depth-of-binary-tree
0112-path-sum
0117-populating-next-right-pointers-in-each-node-ii
0127-word-ladder
0130-surrounded-regions
0133-clone-graph
0199-binary-tree-right-side-view
0200-number-of-islands
0207-course-schedule
0210-course-schedule-ii
0322-coin-change
0399-evaluate-division
0433-minimum-genetic-mutation
0530-minimum-absolute-difference-in-bst
0547-number-of-provinces
0637-average-of-levels-in-binary-tree
0841-keys-and-rooms
0909-snakes-and-ladders
0994-rotting-oranges
1161-maximum-level-sum-of-a-binary-tree
1448-count-good-nodes-in-binary-tree
1466-reorder-routes-to-make-all-paths-lead-to-the-city-zero
1926-nearest-exit-from-entrance-in-maze

Union-Find

0128-longest-consecutive-sequence
0130-surrounded-regions
0200-number-of-islands
0399-evaluate-division
0547-number-of-provinces

Graph Theory

0133-clone-graph
0207-course-schedule
0210-course-schedule-ii
0399-evaluate-division
0547-number-of-provinces
0841-keys-and-rooms
1466-reorder-routes-to-make-all-paths-lead-to-the-city-zero

Shortest Path

0399-evaluate-division

Queue

0649-dota2-senate
0918-maximum-sum-circular-subarray

Tree

0098-validate-binary-search-tree
0100-same-tree
0101-symmetric-tree
0102-binary-tree-level-order-traversal
0103-binary-tree-zigzag-level-order-traversal
0104-maximum-depth-of-binary-tree
0105-construct-binary-tree-from-preorder-and-inorder-traversal
0106-construct-binary-tree-from-inorder-and-postorder-traversal
0108-convert-sorted-array-to-binary-search-tree
0112-path-sum
0114-flatten-binary-tree-to-linked-list
0117-populating-next-right-pointers-in-each-node-ii
0129-sum-root-to-leaf-numbers
0173-binary-search-tree-iterator
0199-binary-tree-right-side-view
0222-count-complete-tree-nodes
0230-kth-smallest-element-in-a-bst
0236-lowest-common-ancestor-of-a-binary-tree
0427-construct-quad-tree
0437-path-sum-iii
0450-delete-node-in-a-bst
0530-minimum-absolute-difference-in-bst
0637-average-of-levels-in-binary-tree
0700-search-in-a-binary-search-tree
0872-leaf-similar-trees
1161-maximum-level-sum-of-a-binary-tree
1372-longest-zigzag-path-in-a-binary-tree
1448-count-good-nodes-in-binary-tree

Binary Tree

0098-validate-binary-search-tree
0100-same-tree
0101-symmetric-tree
0102-binary-tree-level-order-traversal
0103-binary-tree-zigzag-level-order-traversal
0104-maximum-depth-of-binary-tree
0105-construct-binary-tree-from-preorder-and-inorder-traversal
0106-construct-binary-tree-from-inorder-and-postorder-traversal
0108-convert-sorted-array-to-binary-search-tree
0112-path-sum
0114-flatten-binary-tree-to-linked-list
0117-populating-next-right-pointers-in-each-node-ii
0129-sum-root-to-leaf-numbers
0173-binary-search-tree-iterator
0199-binary-tree-right-side-view
0222-count-complete-tree-nodes
0230-kth-smallest-element-in-a-bst
0236-lowest-common-ancestor-of-a-binary-tree
0437-path-sum-iii
0450-delete-node-in-a-bst
0530-minimum-absolute-difference-in-bst
0637-average-of-levels-in-binary-tree
0700-search-in-a-binary-search-tree
0872-leaf-similar-trees
1161-maximum-level-sum-of-a-binary-tree
1372-longest-zigzag-path-in-a-binary-tree
1448-count-good-nodes-in-binary-tree

Binary Search Tree

0098-validate-binary-search-tree
0108-convert-sorted-array-to-binary-search-tree
0173-binary-search-tree-iterator
0230-kth-smallest-element-in-a-bst
0450-delete-node-in-a-bst
0530-minimum-absolute-difference-in-bst
0700-search-in-a-binary-search-tree

Interactive

0374-guess-number-higher-or-lower

Counting Sort

0274-h-index

String Matching

0028-find-the-index-of-the-first-occurrence-in-a-string

Sliding Window

0219-contains-duplicate-ii

Iterator

0173-binary-search-tree-iterator

Topological Sort

0207-course-schedule
0210-course-schedule-ii

Memoization

0070-climbing-stairs
0139-word-break

Geometry

0149-max-points-on-a-line

Merge Sort

0023-merge-k-sorted-lists
0148-sort-list

Monotonic Queue

0918-maximum-sum-circular-subarray

Data Stream

0295-find-median-from-data-stream

Database

0180-consecutive-numbers
0550-game-play-analysis-iv
0570-managers-with-at-least-5-direct-reports
0596-classes-with-at-least-5-students
0610-triangle-judgement
0619-biggest-single-number
0620-not-boring-movies
0626-exchange-seats
1070-product-sales-analysis-iii
1075-project-employees-i
1164-product-price-at-a-given-date
1174-immediate-food-delivery-ii
1204-last-person-to-fit-in-the-bus
1211-queries-quality-and-percentage
1251-average-selling-price
1280-students-and-examinations
1633-percentage-of-users-attended-a-contest
1661-average-time-of-process-per-machine
1729-find-followers-count
1731-the-number-of-employees-which-report-to-each-employee
1789-primary-department-for-each-employee
1907-count-salary-categories
1934-confirmation-rate
1978-employees-whose-manager-left-the-company
2356-number-of-unique-subjects-taught-by-each-teacher