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

LeetCode Topics

String

0003-longest-substring-without-repeating-characters
0038-count-and-say
0049-group-anagrams
0127-word-ladder
0187-repeated-dna-sequences
0395-longest-substring-with-at-least-k-repeating-characters
0438-find-all-anagrams-in-a-string
0516-longest-palindromic-subsequence
0541-reverse-string-ii
0583-delete-operation-for-two-strings
0749-shortest-completing-word
0808-number-of-matching-subsequences
0868-push-dominoes
1170-shortest-common-supersequence
1250-longest-common-subsequence
1302-delete-characters-to-make-fancy-string
1350-remove-sub-folders-from-the-filesystem
1818-maximum-score-from-removing-substrings
1960-check-if-the-sentence-is-pangram
2134-maximize-the-confusion-of-an-exam
2221-check-if-a-parentheses-string-can-be-valid
2346-largest-3-same-digit-number-in-string
2520-using-a-robot-to-print-the-lexicographically-smallest-string
3617-find-the-original-typed-string-i
3618-find-the-original-typed-string-ii

Dynamic Programming

0118-pascals-triangle
0322-coin-change
0413-arithmetic-slices
0416-partition-equal-subset-sum
0516-longest-palindromic-subsequence
0518-coin-change-ii
0542-01-matrix
0583-delete-operation-for-two-strings
0808-number-of-matching-subsequences
0868-push-dominoes
0875-longest-mountain-in-array
1170-shortest-common-supersequence
1250-longest-common-subsequence
1586-longest-subarray-of-1s-after-deleting-one-element
2028-the-earliest-and-latest-rounds-where-players-compete
2267-minimum-difference-in-sums-after-removal-of-elements
2882-ways-to-express-an-integer-as-sum-of-powers
3491-find-the-maximum-length-of-valid-subsequence-ii
3618-find-the-original-typed-string-ii

Prefix Sum

0209-minimum-size-subarray-sum
0304-range-sum-query-2d-immutable
1514-minimum-value-to-get-positive-step-by-step-sum
2134-maximize-the-confusion-of-an-exam
2538-minimum-cost-to-make-array-equal
3618-find-the-original-typed-string-ii
3980-best-time-to-buy-and-sell-stock-using-strategy

Math

0066-plus-one
0069-sqrtx
0231-power-of-two
0326-power-of-three
0342-power-of-four
0453-minimum-moves-to-equal-array-elements
0900-reordered-power-of-2
1411-convert-binary-number-in-a-linked-list-to-integer
1448-maximum-69-number
3600-find-the-k-th-character-in-string-game-i
3601-find-the-k-th-character-in-string-game-ii

Bit Manipulation

0187-repeated-dna-sequences
0231-power-of-two
0342-power-of-four
2170-count-number-of-maximum-bitwise-or-subsets
3600-find-the-k-th-character-in-string-game-i
3601-find-the-k-th-character-in-string-game-ii

Recursion

0231-power-of-two
0326-power-of-three
0342-power-of-four
3600-find-the-k-th-character-in-string-game-i
3601-find-the-k-th-character-in-string-game-ii

Simulation

0498-diagonal-traverse
2048-build-array-from-permutation
2479-meeting-rooms-iii
3600-find-the-k-th-character-in-string-game-i
3790-fruits-into-baskets-ii
3974-xor-after-range-multiplication-queries-i

Array

0015-3sum
0026-remove-duplicates-from-sorted-array
0049-group-anagrams
0056-merge-intervals
0066-plus-one
0118-pascals-triangle
0209-minimum-size-subarray-sum
0239-sliding-window-maximum
0283-move-zeroes
0304-range-sum-query-2d-immutable
0322-coin-change
0349-intersection-of-two-arrays
0350-intersection-of-two-arrays-ii
0413-arithmetic-slices
0416-partition-equal-subset-sum
0453-minimum-moves-to-equal-array-elements
0498-diagonal-traverse
0518-coin-change-ii
0542-01-matrix
0733-flood-fill
0749-shortest-completing-word
0808-number-of-matching-subsequences
0875-longest-mountain-in-array
1002-maximum-width-ramp
1036-rotting-oranges
1073-number-of-enclaves
1350-remove-sub-folders-from-the-filesystem
1468-check-if-n-and-its-double-exist
1514-minimum-value-to-get-positive-step-by-step-sum
1586-longest-subarray-of-1s-after-deleting-one-element
1813-maximum-erasure-value
1878-check-if-array-is-sorted-and-rotated
1995-finding-pairs-with-a-certain-sum
2048-build-array-from-permutation
2170-count-number-of-maximum-bitwise-or-subsets
2267-minimum-difference-in-sums-after-removal-of-elements
2316-count-hills-and-valleys-in-an-array
2479-meeting-rooms-iii
2497-maximum-matching-of-players-with-trainers
2538-minimum-cost-to-make-array-equal
3335-minimum-operations-to-write-the-letter-y-on-a-grid
3491-find-the-maximum-length-of-valid-subsequence-ii
3621-minimum-operations-to-make-array-values-equal-to-k
3741-reschedule-meetings-for-maximum-free-time-ii
3743-reschedule-meetings-for-maximum-free-time-i
3790-fruits-into-baskets-ii
3974-xor-after-range-multiplication-queries-i
3980-best-time-to-buy-and-sell-stock-using-strategy

Hash Table

0003-longest-substring-without-repeating-characters
0049-group-anagrams
0127-word-ladder
0187-repeated-dna-sequences
0349-intersection-of-two-arrays
0350-intersection-of-two-arrays-ii
0395-longest-substring-with-at-least-k-repeating-characters
0438-find-all-anagrams-in-a-string
0749-shortest-completing-word
0808-number-of-matching-subsequences
0900-reordered-power-of-2
1468-check-if-n-and-its-double-exist
1813-maximum-erasure-value
1960-check-if-the-sentence-is-pangram
1995-finding-pairs-with-a-certain-sum
2479-meeting-rooms-iii
2520-using-a-robot-to-print-the-lexicographically-smallest-string
3335-minimum-operations-to-write-the-letter-y-on-a-grid
3621-minimum-operations-to-make-array-values-equal-to-k

Design

0304-range-sum-query-2d-immutable
1995-finding-pairs-with-a-certain-sum

Greedy

1448-maximum-69-number
1818-maximum-score-from-removing-substrings
2221-check-if-a-parentheses-string-can-be-valid
2497-maximum-matching-of-players-with-trainers
2520-using-a-robot-to-print-the-lexicographically-smallest-string
2538-minimum-cost-to-make-array-equal
3741-reschedule-meetings-for-maximum-free-time-ii
3743-reschedule-meetings-for-maximum-free-time-i

Sliding Window

0003-longest-substring-without-repeating-characters
0187-repeated-dna-sequences
0209-minimum-size-subarray-sum
0239-sliding-window-maximum
0395-longest-substring-with-at-least-k-repeating-characters
0413-arithmetic-slices
0438-find-all-anagrams-in-a-string
1586-longest-subarray-of-1s-after-deleting-one-element
1813-maximum-erasure-value
2134-maximize-the-confusion-of-an-exam
3743-reschedule-meetings-for-maximum-free-time-i
3980-best-time-to-buy-and-sell-stock-using-strategy

Sorting

0015-3sum
0049-group-anagrams
0056-merge-intervals
0349-intersection-of-two-arrays
0350-intersection-of-two-arrays-ii
0808-number-of-matching-subsequences
0900-reordered-power-of-2
1468-check-if-n-and-its-double-exist
2479-meeting-rooms-iii
2497-maximum-matching-of-players-with-trainers
2538-minimum-cost-to-make-array-equal

Heap (Priority Queue)

0239-sliding-window-maximum
2267-minimum-difference-in-sums-after-removal-of-elements
2479-meeting-rooms-iii

Enumeration

0875-longest-mountain-in-array
0900-reordered-power-of-2
2170-count-number-of-maximum-bitwise-or-subsets
3741-reschedule-meetings-for-maximum-free-time-ii

Memoization

2028-the-earliest-and-latest-rounds-where-players-compete

Two Pointers

0015-3sum
0026-remove-duplicates-from-sorted-array
0283-move-zeroes
0349-intersection-of-two-arrays
0350-intersection-of-two-arrays-ii
0541-reverse-string-ii
0868-push-dominoes
0875-longest-mountain-in-array
1002-maximum-width-ramp
1468-check-if-n-and-its-double-exist
2497-maximum-matching-of-players-with-trainers

Linked List

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

Depth-First Search

0207-course-schedule
0210-course-schedule-ii
0547-number-of-provinces
0733-flood-fill
0801-is-graph-bipartite
0813-all-paths-from-source-to-target
0820-find-eventual-safe-states
1073-number-of-enclaves
1350-remove-sub-folders-from-the-filesystem
2121-find-if-path-exists-in-graph

Trie

0808-number-of-matching-subsequences
1350-remove-sub-folders-from-the-filesystem

Stack

1002-maximum-width-ramp
1818-maximum-score-from-removing-substrings
2221-check-if-a-parentheses-string-can-be-valid
2520-using-a-robot-to-print-the-lexicographically-smallest-string

Binary Search

0069-sqrtx
0209-minimum-size-subarray-sum
0349-intersection-of-two-arrays
0350-intersection-of-two-arrays-ii
0808-number-of-matching-subsequences
1468-check-if-n-and-its-double-exist
2134-maximize-the-confusion-of-an-exam
2538-minimum-cost-to-make-array-equal
3790-fruits-into-baskets-ii

Segment Tree

3790-fruits-into-baskets-ii

Breadth-First Search

0127-word-ladder
0207-course-schedule
0210-course-schedule-ii
0322-coin-change
0542-01-matrix
0547-number-of-provinces
0733-flood-fill
0801-is-graph-bipartite
0813-all-paths-from-source-to-target
0820-find-eventual-safe-states
1036-rotting-oranges
1073-number-of-enclaves
2121-find-if-path-exists-in-graph

Union Find

0547-number-of-provinces
0801-is-graph-bipartite
1073-number-of-enclaves
2121-find-if-path-exists-in-graph

Graph

0207-course-schedule
0210-course-schedule-ii
0547-number-of-provinces
0801-is-graph-bipartite
0813-all-paths-from-source-to-target
0820-find-eventual-safe-states
2121-find-if-path-exists-in-graph

Backtracking

0813-all-paths-from-source-to-target
2170-count-number-of-maximum-bitwise-or-subsets

Topological Sort

0207-course-schedule
0210-course-schedule-ii
0820-find-eventual-safe-states

Matrix

0304-range-sum-query-2d-immutable
0498-diagonal-traverse
0542-01-matrix
0733-flood-fill
1036-rotting-oranges
1073-number-of-enclaves
3335-minimum-operations-to-write-the-letter-y-on-a-grid

Rolling Hash

0187-repeated-dna-sequences

Hash Function

0187-repeated-dna-sequences

Divide and Conquer

0395-longest-substring-with-at-least-k-repeating-characters
3974-xor-after-range-multiplication-queries-i

Queue

0239-sliding-window-maximum

Monotonic Queue

0239-sliding-window-maximum

Monotonic Stack

1002-maximum-width-ramp

Counting

0900-reordered-power-of-2
3335-minimum-operations-to-write-the-letter-y-on-a-grid

Database

0595-big-countries
1258-article-views-i
1509-replace-employee-id-with-the-unique-identifier