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

LeetCode Topics

Array

0016-3sum-closest
0018-4sum
0031-next-permutation
0037-sudoku-solver
0059-spiral-matrix-ii
0081-search-in-rotated-sorted-array-ii
0212-word-search-ii
0229-majority-element-ii
0377-combination-sum-iv
0417-pacific-atlantic-water-flow
0442-find-all-duplicates-in-an-array
0453-minimum-moves-to-equal-array-elements
0518-coin-change-ii
0611-valid-triangle-number
0628-maximum-product-of-three-numbers
0667-beautiful-arrangement-ii
0673-number-of-longest-increasing-subsequence
0748-largest-number-at-least-twice-of-others
0779-max-chunks-to-make-sorted-ii
0794-swim-in-rising-water
0797-rabbits-in-forest
0819-minimum-swaps-to-make-sequences-increasing
0828-chalkboard-xor-game
0864-image-overlap
0879-maximize-distance-to-closest-person
0968-beautiful-array
1003-minimum-area-rectangle-ii
1020-longest-turbulent-subarray
1049-minimum-domino-rotations-for-equal-row
1080-camelcase-matching
1230-maximum-of-absolute-value-expression
1232-sum-of-mutated-array-closest-to-target
1247-decrease-elements-to-make-array-zigzag
1286-constrained-subsequence-sum
1288-maximum-subarray-sum-with-one-deletion
1290-make-array-strictly-increasing
1293-three-consecutive-odds
1294-range-frequency-queries
1306-minimum-absolute-difference
1335-maximum-candies-allocated-to-k-children
1367-maximum-height-by-stacking-cuboids
1372-check-if-it-is-a-good-array
1378-cells-with-odd-values-in-a-matrix
1381-maximum-score-words-formed-by-letters
1393-maximum-value-of-k-coins-from-piles
1436-get-watched-videos-by-your-friends
1457-minimum-difficulty-of-a-job-schedule
1503-reducing-dishes
1547-destination-city
1550-find-the-kth-smallest-sum-of-a-matrix-with-sorted-rows
1696-strange-printer-ii
1723-maximum-number-of-achievable-transfer-requests
1748-best-team-with-no-conflicts
1815-checking-existence-of-edge-length-limited-paths
1834-minimum-number-of-people-to-teach
1840-minimize-hamming-distance-after-swap-operations
1843-number-of-rectangles-that-can-form-the-largest-square
1878-check-if-array-is-sorted-and-rotated
1902-car-fleet-ii
1918-maximum-score-of-a-good-subarray
1993-sum-of-all-subset-xor-totals
2000-minimum-speed-to-arrive-on-time
2048-build-array-from-permutation
2049-eliminate-maximum-number-of-monsters
2096-find-the-longest-valid-obstacle-course-at-each-position
2106-find-greatest-common-divisor-of-array
2123-the-number-of-weak-characters-in-the-game
2138-sum-of-beauty-in-the-array
2139-detect-squares
2165-plates-between-candles
2189-maximum-path-quality-of-a-graph
2192-minimum-cost-homecoming-of-a-robot-in-a-grid
2193-count-fertile-pyramids-in-a-land
2212-removing-minimum-and-maximum-from-array
2228-watering-plants-ii
2233-number-of-smooth-descent-periods-of-a-stock
2277-count-equal-and-divisible-pairs-in-an-array
2435-shortest-impossible-sequence-of-rolls
2483-task-scheduler-ii
2505-number-of-good-paths
2508-maximum-sum-of-an-hourglass
2518-the-employee-that-worked-on-the-longest-task
2527-count-subarrays-with-fixed-bounds
2529-range-product-queries-of-powers
2539-minimum-number-of-operations-to-make-arrays-similar
2543-most-popular-video-creator
2588-maximum-number-of-points-from-grid-queries
2640-maximum-number-of-integers-to-choose-from-a-range-i
2665-minimum-time-to-repair-cars
2686-minimum-cost-of-a-path-with-special-roads
2694-find-the-maximum-divisibility-score
2721-sum-of-distances
2780-make-costs-of-paths-equal-in-a-binary-tree
3242-count-elements-with-maximum-frequency
3348-minimum-cost-walk-in-weighted-graph
3471-minimum-average-of-smallest-and-largest-elements
3507-find-the-count-of-numbers-which-are-not-special
3515-find-if-digit-game-can-be-won
3657-check-if-grid-can-be-cut-into-sections
3707-find-the-most-common-response
3732-calculate-score-after-performing-instructions
3738-make-array-non-decreasing
3750-closest-equal-element-queries
3788-maximum-unique-subarray-sum-after-deletion
3795-zero-array-transformation-iv
3797-design-spreadsheet
3809-properties-graph
3822-fill-a-special-grid
3832-minimum-cost-to-reach-every-position
3838-path-existence-queries-in-a-graph-i

Two Pointers

0016-3sum-closest
0018-4sum
0031-next-permutation
0160-intersection-of-two-linked-lists
0611-valid-triangle-number
1080-camelcase-matching
1815-checking-existence-of-edge-length-limited-paths
1918-maximum-score-of-a-good-subarray
2228-watering-plants-ii
2588-maximum-number-of-points-from-grid-queries
3471-minimum-average-of-smallest-and-largest-elements
3793-longest-palindrome-after-substring-concatenation-i
3808-longest-palindrome-after-substring-concatenation-ii

Sorting

0016-3sum-closest
0018-4sum
0229-majority-element-ii
0611-valid-triangle-number
0628-maximum-product-of-three-numbers
0748-largest-number-at-least-twice-of-others
0779-max-chunks-to-make-sorted-ii
1232-sum-of-mutated-array-closest-to-target
1290-make-array-strictly-increasing
1306-minimum-absolute-difference
1367-maximum-height-by-stacking-cuboids
1436-get-watched-videos-by-your-friends
1503-reducing-dishes
1613-find-critical-and-pseudo-critical-edges-in-minimum-spanning-tree
1748-best-team-with-no-conflicts
1815-checking-existence-of-edge-length-limited-paths
2049-eliminate-maximum-number-of-monsters
2123-the-number-of-weak-characters-in-the-game
2505-number-of-good-paths
2539-minimum-number-of-operations-to-make-arrays-similar
2543-most-popular-video-creator
2588-maximum-number-of-points-from-grid-queries
2640-maximum-number-of-integers-to-choose-from-a-range-i
3471-minimum-average-of-smallest-and-largest-elements
3657-check-if-grid-can-be-cut-into-sections
3812-smallest-palindromic-rearrangement-i

Math

0007-reverse-integer
0043-multiply-strings
0089-gray-code
0223-rectangle-area
0224-basic-calculator
0227-basic-calculator-ii
0258-add-digits
0372-super-pow
0375-guess-number-higher-or-lower-ii
0382-linked-list-random-node
0453-minimum-moves-to-equal-array-elements
0492-construct-the-rectangle
0593-valid-square
0628-maximum-product-of-three-numbers
0667-beautiful-arrangement-ii
0738-monotone-increasing-digits
0797-rabbits-in-forest
0804-rotated-digits
0809-preimage-size-of-factorial-zeroes-function
0828-chalkboard-xor-game
0956-number-of-music-playlists
0968-beautiful-array
1003-minimum-area-rectangle-ii
1194-path-in-zigzag-labelled-binary-tree
1230-maximum-of-absolute-value-expression
1276-closest-divisors
1359-circular-permutation-in-binary-representation
1372-check-if-it-is-a-good-array
1378-cells-with-odd-values-in-a-matrix
1501-circle-and-rectangle-overlapping
1630-count-odd-numbers-in-an-interval-range
1725-number-of-sets-of-k-non-overlapping-line-segments
1800-concatenation-of-consecutive-binary-numbers
1879-maximum-score-from-removing-stones
1889-check-if-number-is-a-sum-of-powers-of-three
1902-car-fleet-ii
1993-sum-of-all-subset-xor-totals
2032-largest-odd-number-in-string
2106-find-greatest-common-divisor-of-array
2233-number-of-smooth-descent-periods-of-a-stock
2595-smallest-value-after-replacing-with-sum-of-prime-factors
2998-count-symmetric-integers
3507-find-the-count-of-numbers-which-are-not-special
3515-find-if-digit-game-can-be-won
3754-maximum-manhattan-distance-after-k-changes
3817-maximum-containers-on-a-ship

Dynamic Programming

0095-unique-binary-search-trees-ii
0375-guess-number-higher-or-lower-ii
0377-combination-sum-iv
0518-coin-change-ii
0576-out-of-boundary-paths
0673-number-of-longest-increasing-subsequence
0730-count-different-palindromic-subsequences
0804-rotated-digits
0819-minimum-swaps-to-make-sequences-increasing
0877-shortest-path-visiting-all-nodes
0956-number-of-music-playlists
1020-longest-turbulent-subarray
1286-constrained-subsequence-sum
1288-maximum-subarray-sum-with-one-deletion
1290-make-array-strictly-increasing
1332-count-vowels-permutation
1367-maximum-height-by-stacking-cuboids
1381-maximum-score-words-formed-by-letters
1393-maximum-value-of-k-coins-from-piles
1403-palindrome-partitioning-iii
1457-minimum-difficulty-of-a-job-schedule
1475-maximum-sum-bst-in-binary-tree
1503-reducing-dishes
1725-number-of-sets-of-k-non-overlapping-line-segments
1740-count-subtrees-with-max-distance-between-cities
1748-best-team-with-no-conflicts
2193-count-fertile-pyramids-in-a-land
2233-number-of-smooth-descent-periods-of-a-stock
2404-number-of-distinct-roll-sequences
2710-minimum-operations-to-reduce-an-integer-to-0
2780-make-costs-of-paths-equal-in-a-binary-tree
3793-longest-palindrome-after-substring-concatenation-i
3795-zero-array-transformation-iv
3808-longest-palindrome-after-substring-concatenation-ii

Depth-First Search

0417-pacific-atlantic-water-flow
0794-swim-in-rising-water
0801-is-graph-bipartite
1011-flip-binary-tree-to-match-preorder-traversal
1157-insufficient-nodes-in-root-to-leaf-paths
1309-sort-items-by-groups-respecting-dependencies
1475-maximum-sum-bst-in-binary-tree
1558-course-schedule-iv
1643-number-of-nodes-in-the-sub-tree-with-the-same-label
1840-minimize-hamming-distance-after-swap-operations
2583-divide-nodes-into-the-maximum-number-of-groups
3729-unit-conversion-i
3809-properties-graph

Breadth-First Search

0417-pacific-atlantic-water-flow
0794-swim-in-rising-water
0801-is-graph-bipartite
0877-shortest-path-visiting-all-nodes
1309-sort-items-by-groups-respecting-dependencies
1436-get-watched-videos-by-your-friends
1558-course-schedule-iv
1643-number-of-nodes-in-the-sub-tree-with-the-same-label
2583-divide-nodes-into-the-maximum-number-of-groups
2588-maximum-number-of-points-from-grid-queries
3729-unit-conversion-i
3809-properties-graph

Graph

0801-is-graph-bipartite
0877-shortest-path-visiting-all-nodes
1309-sort-items-by-groups-respecting-dependencies
1436-get-watched-videos-by-your-friends
1558-course-schedule-iv
1613-find-critical-and-pseudo-critical-edges-in-minimum-spanning-tree
1696-strange-printer-ii
1815-checking-existence-of-edge-length-limited-paths
2189-maximum-path-quality-of-a-graph
2455-node-with-highest-edge-score
2505-number-of-good-paths
2583-divide-nodes-into-the-maximum-number-of-groups
2686-minimum-cost-of-a-path-with-special-roads
2803-modify-graph-edge-weights
3348-minimum-cost-walk-in-weighted-graph
3729-unit-conversion-i
3809-properties-graph
3838-path-existence-queries-in-a-graph-i

Topological Sort

1309-sort-items-by-groups-respecting-dependencies
1558-course-schedule-iv
1696-strange-printer-ii

Greedy

0611-valid-triangle-number
0738-monotone-increasing-digits
0779-max-chunks-to-make-sorted-ii
0797-rabbits-in-forest
1049-minimum-domino-rotations-for-equal-row
1247-decrease-elements-to-make-array-zigzag
1503-reducing-dishes
1834-minimum-number-of-people-to-teach
1879-maximum-score-from-removing-stones
2032-largest-odd-number-in-string
2049-eliminate-maximum-number-of-monsters
2123-the-number-of-weak-characters-in-the-game
2192-minimum-cost-homecoming-of-a-robot-in-a-grid
2212-removing-minimum-and-maximum-from-array
2435-shortest-impossible-sequence-of-rolls
2539-minimum-number-of-operations-to-make-arrays-similar
2640-maximum-number-of-integers-to-choose-from-a-range-i
2710-minimum-operations-to-reduce-an-integer-to-0
2780-make-costs-of-paths-equal-in-a-binary-tree
3738-make-array-non-decreasing
3788-maximum-unique-subarray-sum-after-deletion

Linked List

0160-intersection-of-two-linked-lists
0382-linked-list-random-node

Reservoir Sampling

0382-linked-list-random-node

Randomized

0382-linked-list-random-node

String

0038-count-and-say
0043-multiply-strings
0208-implement-trie-prefix-tree
0212-word-search-ii
0224-basic-calculator
0227-basic-calculator-ii
0730-count-different-palindromic-subsequences
0763-special-binary-string
0800-letter-case-permutation
0916-decoded-string-at-index
1065-binary-string-with-substrings-representing-1-to-n
1080-camelcase-matching
1381-maximum-score-words-formed-by-letters
1403-palindrome-partitioning-iii
1473-find-the-longest-substring-containing-vowels-in-even-counts
1547-destination-city
1859-change-minimum-characters-to-satisfy-one-of-three-conditions
1933-number-of-different-integers-in-a-string
1960-check-if-the-sentence-is-pangram
1999-longer-contiguous-segments-of-ones-than-zeros
2032-largest-odd-number-in-string
2053-check-if-all-characters-have-equal-number-of-occurrences
2165-plates-between-candles
2543-most-popular-video-creator
2632-apply-bitwise-operations-to-make-strings-equal
3707-find-the-most-common-response
3709-find-special-substring-of-length-k
3732-calculate-score-after-performing-instructions
3754-maximum-manhattan-distance-after-k-changes
3793-longest-palindrome-after-substring-concatenation-i
3797-design-spreadsheet
3808-longest-palindrome-after-substring-concatenation-ii
3812-smallest-palindromic-rearrangement-i

Union Find

0794-swim-in-rising-water
0801-is-graph-bipartite
1613-find-critical-and-pseudo-critical-edges-in-minimum-spanning-tree
1815-checking-existence-of-edge-length-limited-paths
1840-minimize-hamming-distance-after-swap-operations
2505-number-of-good-paths
2583-divide-nodes-into-the-maximum-number-of-groups
2588-maximum-number-of-points-from-grid-queries
3348-minimum-cost-walk-in-weighted-graph
3809-properties-graph
3838-path-existence-queries-in-a-graph-i

Number Theory

0258-add-digits
1372-check-if-it-is-a-good-array
2106-find-greatest-common-divisor-of-array
2595-smallest-value-after-replacing-with-sum-of-prime-factors
3507-find-the-count-of-numbers-which-are-not-special

Hash Table

0037-sudoku-solver
0160-intersection-of-two-linked-lists
0208-implement-trie-prefix-tree
0229-majority-element-ii
0442-find-all-duplicates-in-an-array
0797-rabbits-in-forest
0931-maximum-frequency-stack
1294-range-frequency-queries
1436-get-watched-videos-by-your-friends
1473-find-the-longest-substring-containing-vowels-in-even-counts
1547-destination-city
1643-number-of-nodes-in-the-sub-tree-with-the-same-label
1834-minimum-number-of-people-to-teach
1859-change-minimum-characters-to-satisfy-one-of-three-conditions
1933-number-of-different-integers-in-a-string
1960-check-if-the-sentence-is-pangram
2053-check-if-all-characters-have-equal-number-of-occurrences
2139-detect-squares
2435-shortest-impossible-sequence-of-rolls
2455-node-with-highest-edge-score
2483-task-scheduler-ii
2505-number-of-good-paths
2543-most-popular-video-creator
2640-maximum-number-of-integers-to-choose-from-a-range-i
2721-sum-of-distances
3242-count-elements-with-maximum-frequency
3678-design-task-manager
3707-find-the-most-common-response
3732-calculate-score-after-performing-instructions
3750-closest-equal-element-queries
3754-maximum-manhattan-distance-after-k-changes
3788-maximum-unique-subarray-sum-after-deletion
3797-design-spreadsheet
3809-properties-graph

Stack

0224-basic-calculator
0225-implement-stack-using-queues
0227-basic-calculator-ii
0779-max-chunks-to-make-sorted-ii
0916-decoded-string-at-index
0931-maximum-frequency-stack
1902-car-fleet-ii
1918-maximum-score-of-a-good-subarray
2123-the-number-of-weak-characters-in-the-game
3738-make-array-non-decreasing

Design

0208-implement-trie-prefix-tree
0225-implement-stack-using-queues
0352-data-stream-as-disjoint-intervals
0931-maximum-frequency-stack
1294-range-frequency-queries
2139-detect-squares
3678-design-task-manager
3797-design-spreadsheet

Ordered Set

0352-data-stream-as-disjoint-intervals
0931-maximum-frequency-stack
3678-design-task-manager

Binary Search

0081-search-in-rotated-sorted-array-ii
0352-data-stream-as-disjoint-intervals
0611-valid-triangle-number
0794-swim-in-rising-water
0809-preimage-size-of-factorial-zeroes-function
1232-sum-of-mutated-array-closest-to-target
1290-make-array-strictly-increasing
1294-range-frequency-queries
1335-maximum-candies-allocated-to-k-children
1550-find-the-kth-smallest-sum-of-a-matrix-with-sorted-rows
1918-maximum-score-of-a-good-subarray
2000-minimum-speed-to-arrive-on-time
2096-find-the-longest-valid-obstacle-course-at-each-position
2165-plates-between-candles
2640-maximum-number-of-integers-to-choose-from-a-range-i
2665-minimum-time-to-repair-cars
3750-closest-equal-element-queries
3838-path-existence-queries-in-a-graph-i

Monotonic Stack

0779-max-chunks-to-make-sorted-ii
1902-car-fleet-ii
1918-maximum-score-of-a-good-subarray
2123-the-number-of-weak-characters-in-the-game
3738-make-array-non-decreasing

Recursion

0224-basic-calculator
0763-special-binary-string

Bit Manipulation

0089-gray-code
0800-letter-case-permutation
0828-chalkboard-xor-game
0877-shortest-path-visiting-all-nodes
1359-circular-permutation-in-binary-representation
1381-maximum-score-words-formed-by-letters
1473-find-the-longest-substring-containing-vowels-in-even-counts
1723-maximum-number-of-achievable-transfer-requests
1740-count-subtrees-with-max-distance-between-cities
1800-concatenation-of-consecutive-binary-numbers
1993-sum-of-all-subset-xor-totals
2529-range-product-queries-of-powers
2632-apply-bitwise-operations-to-make-strings-equal
2710-minimum-operations-to-reduce-an-integer-to-0
3348-minimum-cost-walk-in-weighted-graph

Brainteaser

0828-chalkboard-xor-game

Game Theory

0375-guess-number-higher-or-lower-ii
0828-chalkboard-xor-game

Heap (Priority Queue)

0794-swim-in-rising-water
1286-constrained-subsequence-sum
1550-find-the-kth-smallest-sum-of-a-matrix-with-sorted-rows
1879-maximum-score-from-removing-stones
1902-car-fleet-ii
2543-most-popular-video-creator
2588-maximum-number-of-points-from-grid-queries
2686-minimum-cost-of-a-path-with-special-roads
2803-modify-graph-edge-weights
3678-design-task-manager

Matrix

0037-sudoku-solver
0059-spiral-matrix-ii
0212-word-search-ii
0417-pacific-atlantic-water-flow
0794-swim-in-rising-water
0864-image-overlap
1550-find-the-kth-smallest-sum-of-a-matrix-with-sorted-rows
1696-strange-printer-ii
2193-count-fertile-pyramids-in-a-land
2508-maximum-sum-of-an-hourglass
2588-maximum-number-of-points-from-grid-queries
3797-design-spreadsheet
3822-fill-a-special-grid

Backtracking

0037-sudoku-solver
0089-gray-code
0095-unique-binary-search-trees-ii
0212-word-search-ii
0800-letter-case-permutation
1359-circular-permutation-in-binary-representation
1381-maximum-score-words-formed-by-letters
1723-maximum-number-of-achievable-transfer-requests
1993-sum-of-all-subset-xor-totals
2189-maximum-path-quality-of-a-graph

Trie

0208-implement-trie-prefix-tree
0212-word-search-ii
1080-camelcase-matching

Divide and Conquer

0372-super-pow
0968-beautiful-array
3822-fill-a-special-grid

Tree

0095-unique-binary-search-trees-ii
1011-flip-binary-tree-to-match-preorder-traversal
1040-maximum-binary-tree-ii
1157-insufficient-nodes-in-root-to-leaf-paths
1194-path-in-zigzag-labelled-binary-tree
1475-maximum-sum-bst-in-binary-tree
1643-number-of-nodes-in-the-sub-tree-with-the-same-label
1740-count-subtrees-with-max-distance-between-cities
2505-number-of-good-paths
2780-make-costs-of-paths-equal-in-a-binary-tree

Counting

0229-majority-element-ii
1643-number-of-nodes-in-the-sub-tree-with-the-same-label
1859-change-minimum-characters-to-satisfy-one-of-three-conditions
2053-check-if-all-characters-have-equal-number-of-occurrences
2139-detect-squares
3242-count-elements-with-maximum-frequency
3707-find-the-most-common-response
3754-maximum-manhattan-distance-after-k-changes

Binary Indexed Tree

0673-number-of-longest-increasing-subsequence
2096-find-the-longest-valid-obstacle-course-at-each-position

Segment Tree

0673-number-of-longest-increasing-subsequence
1294-range-frequency-queries

Bitmask

0877-shortest-path-visiting-all-nodes
1381-maximum-score-words-formed-by-letters
1740-count-subtrees-with-max-distance-between-cities

Binary Tree

0095-unique-binary-search-trees-ii
1011-flip-binary-tree-to-match-preorder-traversal
1040-maximum-binary-tree-ii
1157-insufficient-nodes-in-root-to-leaf-paths
1194-path-in-zigzag-labelled-binary-tree
1475-maximum-sum-bst-in-binary-tree
2780-make-costs-of-paths-equal-in-a-binary-tree

Simulation

0043-multiply-strings
0059-spiral-matrix-ii
0258-add-digits
1378-cells-with-odd-values-in-a-matrix
1800-concatenation-of-consecutive-binary-numbers
2048-build-array-from-permutation
2228-watering-plants-ii
2483-task-scheduler-ii
2595-smallest-value-after-replacing-with-sum-of-prime-factors
3732-calculate-score-after-performing-instructions

Geometry

0223-rectangle-area
0593-valid-square
1003-minimum-area-rectangle-ii
1501-circle-and-rectangle-overlapping

Prefix Sum

1393-maximum-value-of-k-coins-from-piles
1473-find-the-longest-substring-containing-vowels-in-even-counts
1859-change-minimum-characters-to-satisfy-one-of-three-conditions
2165-plates-between-candles
2508-maximum-sum-of-an-hourglass
2529-range-product-queries-of-powers
2721-sum-of-distances

Combinatorics

0956-number-of-music-playlists
1725-number-of-sets-of-k-non-overlapping-line-segments
1993-sum-of-all-subset-xor-totals

Enumeration

1723-maximum-number-of-achievable-transfer-requests
1740-count-subtrees-with-max-distance-between-cities
1993-sum-of-all-subset-xor-totals
2998-count-symmetric-integers
3793-longest-palindrome-after-substring-concatenation-i

Queue

0225-implement-stack-using-queues
1286-constrained-subsequence-sum
2527-count-subarrays-with-fixed-bounds

Shortest Path

2686-minimum-cost-of-a-path-with-special-roads
2803-modify-graph-edge-weights

Sliding Window

1020-longest-turbulent-subarray
1286-constrained-subsequence-sum
2527-count-subarrays-with-fixed-bounds

Monotonic Queue

1286-constrained-subsequence-sum
2527-count-subarrays-with-fixed-bounds

Counting Sort

3812-smallest-palindromic-rearrangement-i

Binary Search Tree

0095-unique-binary-search-trees-ii
1475-maximum-sum-bst-in-binary-tree

Minimum Spanning Tree

1613-find-critical-and-pseudo-critical-edges-in-minimum-spanning-tree

Strongly Connected Component

1613-find-critical-and-pseudo-critical-edges-in-minimum-spanning-tree

Memoization

2404-number-of-distinct-roll-sequences

String Matching

1080-camelcase-matching