Leetcode

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

LeetCode Topics

Hash Table

0001-two-sum
0036-valid-sudoku
0049-group-anagrams
0141-linked-list-cycle
0166-fraction-to-recurring-decimal
0169-majority-element
0217-contains-duplicate
0242-valid-anagram
0268-missing-number
0347-top-k-frequent-elements
0560-subarray-sum-equals-k
0575-distribute-candies
1044-find-common-characters
1264-maximum-number-of-words-you-can-type
1346-check-if-n-and-its-double-exist
1813-maximum-erasure-value
2023-design-movie-rental-system
2599-take-k-of-each-character-from-left-and-right
2856-count-complete-subarrays-in-an-array
2954-maximum-sum-of-almost-unique-subarray
2975-maximum-square-area-by-removing-fences-from-a-field
3225-length-of-longest-subarray-with-at-most-k-frequency
3242-count-elements-with-maximum-frequency
3502-count-substrings-with-k-frequency-characters-i
3569-count-of-substrings-containing-every-vowel-and-k-consonants-ii
3570-count-of-substrings-containing-every-vowel-and-k-consonants-i
3573-count-substrings-that-can-be-rearranged-to-contain-a-string-i
3678-design-task-manager

String

0032-longest-valid-parentheses
0049-group-anagrams
0165-compare-version-numbers
0166-fraction-to-recurring-decimal
0242-valid-anagram
1044-find-common-characters
1264-maximum-number-of-words-you-can-type
1351-replace-the-substring-for-balanced-string
1967-longest-substring-of-all-vowels-in-order
2599-take-k-of-each-character-from-left-and-right
2786-find-the-longest-semi-repetitive-substring
2887-sort-vowels-in-a-string
3462-vowels-game-in-a-string
3502-count-substrings-with-k-frequency-characters-i
3569-count-of-substrings-containing-every-vowel-and-k-consonants-ii
3570-count-of-substrings-containing-every-vowel-and-k-consonants-i
3573-count-substrings-that-can-be-rearranged-to-contain-a-string-i

Sliding Window

0413-arithmetic-slices
1351-replace-the-substring-for-balanced-string
1813-maximum-erasure-value
1967-longest-substring-of-all-vowels-in-order
1984-minimum-difference-between-highest-and-lowest-of-k-scores
2599-take-k-of-each-character-from-left-and-right
2673-maximize-win-from-two-segments
2786-find-the-longest-semi-repetitive-substring
2856-count-complete-subarrays-in-an-array
2868-continuous-subarrays
2954-maximum-sum-of-almost-unique-subarray
3213-count-subarrays-where-max-element-appears-at-least-k-times
3225-length-of-longest-subarray-with-at-most-k-frequency
3502-count-substrings-with-k-frequency-characters-i
3569-count-of-substrings-containing-every-vowel-and-k-consonants-ii
3570-count-of-substrings-containing-every-vowel-and-k-consonants-i
3573-count-substrings-that-can-be-rearranged-to-contain-a-string-i
3634-minimum-removals-to-balance-array
3835-count-partitions-with-max-min-difference-at-most-k

Array

0001-two-sum
0031-next-permutation
0036-valid-sudoku
0049-group-anagrams
0053-maximum-subarray
0075-sort-colors
0120-triangle
0121-best-time-to-buy-and-sell-stock
0169-majority-element
0200-number-of-islands
0217-contains-duplicate
0238-product-of-array-except-self
0268-missing-number
0283-move-zeroes
0347-top-k-frequent-elements
0413-arithmetic-slices
0485-max-consecutive-ones
0560-subarray-sum-equals-k
0575-distribute-candies
0830-largest-triangle-area
1018-largest-perimeter-triangle
1037-valid-boomerang
1044-find-common-characters
1111-minimum-score-triangulation-of-polygon
1346-check-if-n-and-its-double-exist
1426-find-n-unique-integers-sum-up-to-zero
1464-maximum-product-of-two-elements-in-an-array
1813-maximum-erasure-value
1984-minimum-difference-between-highest-and-lowest-of-k-scores
2023-design-movie-rental-system
2271-rearrange-array-elements-by-sign
2673-maximize-win-from-two-segments
2706-buy-two-chocolates
2778-sum-of-squares-of-special-elements
2856-count-complete-subarrays-in-an-array
2868-continuous-subarrays
2943-maximize-area-of-square-hole-in-grid
2954-maximum-sum-of-almost-unique-subarray
2975-maximum-square-area-by-removing-fences-from-a-field
3213-count-subarrays-where-max-element-appears-at-least-k-times
3225-length-of-longest-subarray-with-at-most-k-frequency
3242-count-elements-with-maximum-frequency
3634-minimum-removals-to-balance-array
3748-sort-matrix-by-diagonals
3835-count-partitions-with-max-min-difference-at-most-k

Two Pointers

0019-remove-nth-node-from-end-of-list
0031-next-permutation
0075-sort-colors
0141-linked-list-cycle
0165-compare-version-numbers
0283-move-zeroes
0876-middle-of-the-linked-list
1346-check-if-n-and-its-double-exist
1721-swapping-nodes-in-a-linked-list
2271-rearrange-array-elements-by-sign

Math

0166-fraction-to-recurring-decimal
0231-power-of-two
0268-missing-number
0342-power-of-four
0367-valid-perfect-square
0830-largest-triangle-area
1018-largest-perimeter-triangle
1037-valid-boomerang
1426-find-n-unique-integers-sum-up-to-zero
2807-insert-greatest-common-divisors-in-linked-list
3279-alice-and-bob-playing-flower-game
3462-vowels-game-in-a-string
3830-find-closest-person

Binary Search

0268-missing-number
0367-valid-perfect-square
0374-guess-number-higher-or-lower
1346-check-if-n-and-its-double-exist
2673-maximize-win-from-two-segments

Bit Manipulation

0190-reverse-bits
0191-number-of-1-bits
0231-power-of-two
0268-missing-number
0338-counting-bits
0342-power-of-four

Sorting

0049-group-anagrams
0075-sort-colors
0169-majority-element
0217-contains-duplicate
0242-valid-anagram
0268-missing-number
0347-top-k-frequent-elements
1018-largest-perimeter-triangle
1346-check-if-n-and-its-double-exist
1464-maximum-product-of-two-elements-in-an-array
1984-minimum-difference-between-highest-and-lowest-of-k-scores
2706-buy-two-chocolates
2887-sort-vowels-in-a-string
2943-maximize-area-of-square-hole-in-grid
3634-minimum-removals-to-balance-array
3748-sort-matrix-by-diagonals

Divide and Conquer

0053-maximum-subarray
0169-majority-element
0190-reverse-bits
0191-number-of-1-bits
0347-top-k-frequent-elements

Counting

0169-majority-element
0347-top-k-frequent-elements
3242-count-elements-with-maximum-frequency

Dynamic Programming

0032-longest-valid-parentheses
0053-maximum-subarray
0120-triangle
0121-best-time-to-buy-and-sell-stock
0338-counting-bits
0413-arithmetic-slices
1111-minimum-score-triangulation-of-polygon
3835-count-partitions-with-max-min-difference-at-most-k

Matrix

0036-valid-sudoku
0200-number-of-islands
3748-sort-matrix-by-diagonals

Simulation

2271-rearrange-array-elements-by-sign

Queue

2868-continuous-subarrays
3835-count-partitions-with-max-min-difference-at-most-k

Heap (Priority Queue)

0347-top-k-frequent-elements
1464-maximum-product-of-two-elements-in-an-array
2023-design-movie-rental-system
2868-continuous-subarrays
3678-design-task-manager

Ordered Set

2023-design-movie-rental-system
2868-continuous-subarrays
3678-design-task-manager

Monotonic Queue

2868-continuous-subarrays
3835-count-partitions-with-max-min-difference-at-most-k

Prefix Sum

0238-product-of-array-except-self
0560-subarray-sum-equals-k
3835-count-partitions-with-max-min-difference-at-most-k

Brainteaser

3462-vowels-game-in-a-string

Game Theory

3462-vowels-game-in-a-string

Recursion

0203-remove-linked-list-elements
0231-power-of-two
0342-power-of-four

Design

2023-design-movie-rental-system
3678-design-task-manager

Geometry

0830-largest-triangle-area
1037-valid-boomerang

Greedy

1018-largest-perimeter-triangle
2706-buy-two-chocolates

Linked List

0019-remove-nth-node-from-end-of-list
0114-flatten-binary-tree-to-linked-list
0141-linked-list-cycle
0203-remove-linked-list-elements
0328-odd-even-linked-list
0876-middle-of-the-linked-list
1721-swapping-nodes-in-a-linked-list
2807-insert-greatest-common-divisors-in-linked-list

Number Theory

2807-insert-greatest-common-divisors-in-linked-list

Interactive

0374-guess-number-higher-or-lower

Enumeration

2778-sum-of-squares-of-special-elements
2975-maximum-square-area-by-removing-fences-from-a-field

Bucket Sort

0347-top-k-frequent-elements

Quickselect

0347-top-k-frequent-elements

Stack

0032-longest-valid-parentheses
0114-flatten-binary-tree-to-linked-list

Tree

0098-validate-binary-search-tree
0103-binary-tree-zigzag-level-order-traversal
0114-flatten-binary-tree-to-linked-list
0129-sum-root-to-leaf-numbers
0230-kth-smallest-element-in-a-bst
0235-lowest-common-ancestor-of-a-binary-search-tree
0543-diameter-of-binary-tree

Depth-First Search

0098-validate-binary-search-tree
0114-flatten-binary-tree-to-linked-list
0129-sum-root-to-leaf-numbers
0200-number-of-islands
0207-course-schedule
0230-kth-smallest-element-in-a-bst
0235-lowest-common-ancestor-of-a-binary-search-tree
0543-diameter-of-binary-tree

Binary Tree

0098-validate-binary-search-tree
0103-binary-tree-zigzag-level-order-traversal
0114-flatten-binary-tree-to-linked-list
0129-sum-root-to-leaf-numbers
0230-kth-smallest-element-in-a-bst
0235-lowest-common-ancestor-of-a-binary-search-tree
0543-diameter-of-binary-tree

Breadth-First Search

0103-binary-tree-zigzag-level-order-traversal
0200-number-of-islands
0207-course-schedule

Binary Search Tree

0098-validate-binary-search-tree
0230-kth-smallest-element-in-a-bst
0235-lowest-common-ancestor-of-a-binary-search-tree

Union-Find

0200-number-of-islands

Graph Theory

0207-course-schedule

Topological Sort

0207-course-schedule