leetcode

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

LeetCode Topics

Array

0001-two-sum
0004-median-of-two-sorted-arrays
0011-container-with-most-water
0026-remove-duplicates-from-sorted-array
0027-remove-element
0031-next-permutation
0035-search-insert-position
0042-trapping-rain-water
0048-rotate-image
0049-group-anagrams
0053-maximum-subarray
0056-merge-intervals
0066-plus-one
0073-set-matrix-zeroes
0074-search-a-2d-matrix
0075-sort-colors
0088-merge-sorted-array
0118-pascals-triangle
0121-best-time-to-buy-and-sell-stock
0128-longest-consecutive-sequence
0136-single-number
0169-majority-element
0189-rotate-array
0209-minimum-size-subarray-sum
0217-contains-duplicate
0229-majority-element-ii
0238-product-of-array-except-self
0268-missing-number
0283-move-zeroes
0287-find-the-duplicate-number
0485-max-consecutive-ones
0493-reverse-pairs
0561-array-partition
0643-maximum-average-subarray-i
0713-subarray-product-less-than-k
0780-max-chunks-to-make-sorted
0932-monotonic-array
0940-fruit-into-baskets
0948-sort-an-array
1046-max-consecutive-ones-iii
1370-count-number-of-nice-subarrays
1445-number-of-sub-arrays-of-size-k-and-average-greater-than-or-equal-to-threshold
1570-final-prices-with-a-special-discount-in-a-shop
1603-running-sum-of-1d-array
1677-matrix-diagonal-sum
1755-defuse-the-bomb
1781-check-if-two-string-arrays-are-equivalent
1791-richest-customer-wealth
1833-find-the-highest-altitude
1993-sum-of-all-subset-xor-totals
2042-maximum-product-difference-between-two-pairs
2048-build-array-from-permutation
2058-concatenation-of-array
2112-minimum-difference-between-highest-and-lowest-of-k-scores
2219-maximum-number-of-words-found-in-sentences
2248-minimum-cost-of-buying-candies-with-discount
2265-partition-array-according-to-given-pivot
2308-divide-array-into-equal-pairs
2350-find-closest-number-to-zero
2502-sort-the-people
2714-left-and-right-sum-differences
2836-neither-minimum-nor-maximum
2856-count-complete-subarrays-in-an-array
2917-count-pairs-whose-sum-is-less-than-target
3152-maximum-value-of-an-ordered-triplet-ii
3154-maximum-value-of-an-ordered-triplet-i
3194-find-words-containing-character
3227-find-missing-and-repeated-values
3471-minimum-average-of-smallest-and-largest-elements
3475-minimum-operations-to-make-binary-array-elements-equal-to-one-i
3685-count-subarrays-of-length-three-with-a-condition

Math

0002-add-two-numbers
0007-reverse-integer
0029-divide-two-integers
0048-rotate-image
0050-powx-n
0062-unique-paths
0066-plus-one
0189-rotate-array
0231-power-of-two
0268-missing-number
0412-fizz-buzz
1013-fibonacci-number
1370-count-number-of-nice-subarrays
1406-subtract-the-product-and-sum-of-digits-of-an-integer
1610-xor-operation-in-an-array
1993-sum-of-all-subset-xor-totals
2383-add-two-integers
2556-convert-the-temperature
2608-count-the-digits-that-divide-a-number
2752-sum-multiples
3172-divisible-and-non-divisible-sums-difference
3227-find-missing-and-repeated-values
3600-find-the-k-th-character-in-string-game-i
3601-find-the-k-th-character-in-string-game-ii

Matrix

0048-rotate-image
0073-set-matrix-zeroes
0074-search-a-2d-matrix
1677-matrix-diagonal-sum
1791-richest-customer-wealth
3227-find-missing-and-repeated-values

Two Pointers

0011-container-with-most-water
0019-remove-nth-node-from-end-of-list
0026-remove-duplicates-from-sorted-array
0027-remove-element
0031-next-permutation
0042-trapping-rain-water
0075-sort-colors
0088-merge-sorted-array
0125-valid-palindrome
0141-linked-list-cycle
0142-linked-list-cycle-ii
0151-reverse-words-in-a-string
0189-rotate-array
0234-palindrome-linked-list
0283-move-zeroes
0287-find-the-duplicate-number
0344-reverse-string
0345-reverse-vowels-of-a-string
0443-string-compression
0908-middle-of-the-linked-list
0953-reverse-only-letters
1894-merge-strings-alternately
2128-reverse-prefix-of-word
2216-delete-the-middle-node-of-a-linked-list
2236-maximum-twin-sum-of-a-linked-list
2265-partition-array-according-to-given-pivot
2917-count-pairs-whose-sum-is-less-than-target
3471-minimum-average-of-smallest-and-largest-elements

Dynamic Programming

0042-trapping-rain-water
0053-maximum-subarray
0062-unique-paths
0118-pascals-triangle
0121-best-time-to-buy-and-sell-stock
1013-fibonacci-number

Stack

0020-valid-parentheses
0042-trapping-rain-water
0094-binary-tree-inorder-traversal
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0234-palindrome-linked-list
0780-max-chunks-to-make-sorted
1570-final-prices-with-a-special-discount-in-a-shop
2128-reverse-prefix-of-word
2236-maximum-twin-sum-of-a-linked-list
2470-removing-stars-from-a-string
2573-remove-nodes-from-linked-list

Monotonic Stack

0042-trapping-rain-water
0780-max-chunks-to-make-sorted
1570-final-prices-with-a-special-discount-in-a-shop
2573-remove-nodes-from-linked-list

Hash Table

0001-two-sum
0003-longest-substring-without-repeating-characters
0049-group-anagrams
0073-set-matrix-zeroes
0128-longest-consecutive-sequence
0141-linked-list-cycle
0142-linked-list-cycle-ii
0169-majority-element
0217-contains-duplicate
0229-majority-element-ii
0242-valid-anagram
0268-missing-number
0438-find-all-anagrams-in-a-string
0940-fruit-into-baskets
1370-count-number-of-nice-subarrays
1460-number-of-substrings-containing-all-three-characters
1987-substrings-of-size-three-with-distinct-characters
2308-divide-array-into-equal-pairs
2502-sort-the-people
2856-count-complete-subarrays-in-an-array
3227-find-missing-and-repeated-values
3412-permutation-difference-between-two-strings

Database

0175-combine-two-tables
0584-find-customer-referee
0595-big-countries
1258-article-views-i
1827-invalid-tweets
1892-find-total-time-spent-by-each-employee
1908-recyclable-and-low-fat-products
2495-number-of-unique-subjects-taught-by-each-teacher

Simulation

0412-fizz-buzz
2048-build-array-from-permutation
2058-concatenation-of-array
2076-sum-of-digits-of-string-after-convert
2265-partition-array-according-to-given-pivot
2470-removing-stars-from-a-string
3600-find-the-k-th-character-in-string-game-i

Prefix Sum

0209-minimum-size-subarray-sum
0238-product-of-array-except-self
0713-subarray-product-less-than-k
1046-max-consecutive-ones-iii
1370-count-number-of-nice-subarrays
1603-running-sum-of-1d-array
1833-find-the-highest-altitude
2134-maximize-the-confusion-of-an-exam
2714-left-and-right-sum-differences
3475-minimum-operations-to-make-binary-array-elements-equal-to-one-i

Recursion

0002-add-two-numbers
0021-merge-two-sorted-lists
0050-powx-n
0203-remove-linked-list-elements
0206-reverse-linked-list
0231-power-of-two
0234-palindrome-linked-list
1013-fibonacci-number
2573-remove-nodes-from-linked-list
3600-find-the-k-th-character-in-string-game-i
3601-find-the-k-th-character-in-string-game-ii

Memoization

1013-fibonacci-number

String

0003-longest-substring-without-repeating-characters
0020-valid-parentheses
0049-group-anagrams
0125-valid-palindrome
0151-reverse-words-in-a-string
0242-valid-anagram
0344-reverse-string
0345-reverse-vowels-of-a-string
0412-fizz-buzz
0438-find-all-anagrams-in-a-string
0443-string-compression
0520-detect-capital
0742-to-lower-case
0812-rotate-string
0953-reverse-only-letters
1302-delete-characters-to-make-fancy-string
1460-number-of-substrings-containing-all-three-characters
1781-check-if-two-string-arrays-are-equivalent
1894-merge-strings-alternately
1987-substrings-of-size-three-with-distinct-characters
2076-sum-of-digits-of-string-after-convert
2128-reverse-prefix-of-word
2134-maximize-the-confusion-of-an-exam
2219-maximum-number-of-words-found-in-sentences
2470-removing-stars-from-a-string
2502-sort-the-people
2580-circular-sentence
3194-find-words-containing-character
3379-score-of-a-string
3412-permutation-difference-between-two-strings
3543-count-substrings-that-satisfy-k-constraint-i
3617-find-the-original-typed-string-i

Sorting

0049-group-anagrams
0056-merge-intervals
0075-sort-colors
0088-merge-sorted-array
0169-majority-element
0217-contains-duplicate
0229-majority-element-ii
0242-valid-anagram
0268-missing-number
0561-array-partition
0780-max-chunks-to-make-sorted
0948-sort-an-array
2042-maximum-product-difference-between-two-pairs
2112-minimum-difference-between-highest-and-lowest-of-k-scores
2248-minimum-cost-of-buying-candies-with-discount
2502-sort-the-people
2836-neither-minimum-nor-maximum
2917-count-pairs-whose-sum-is-less-than-target
3471-minimum-average-of-smallest-and-largest-elements

Binary Search

0004-median-of-two-sorted-arrays
0035-search-insert-position
0074-search-a-2d-matrix
0209-minimum-size-subarray-sum
0268-missing-number
0287-find-the-duplicate-number
0493-reverse-pairs
0713-subarray-product-less-than-k
1046-max-consecutive-ones-iii
2134-maximize-the-confusion-of-an-exam
2917-count-pairs-whose-sum-is-less-than-target

Bit Manipulation

0029-divide-two-integers
0136-single-number
0231-power-of-two
0268-missing-number
0287-find-the-duplicate-number
1610-xor-operation-in-an-array
1993-sum-of-all-subset-xor-totals
2308-divide-array-into-equal-pairs
3475-minimum-operations-to-make-binary-array-elements-equal-to-one-i
3600-find-the-k-th-character-in-string-game-i
3601-find-the-k-th-character-in-string-game-ii

Divide and Conquer

0004-median-of-two-sorted-arrays
0053-maximum-subarray
0169-majority-element
0493-reverse-pairs
0948-sort-an-array

Greedy

0011-container-with-most-water
0561-array-partition
0780-max-chunks-to-make-sorted
2248-minimum-cost-of-buying-candies-with-discount

Linked List

0002-add-two-numbers
0019-remove-nth-node-from-end-of-list
0021-merge-two-sorted-lists
0083-remove-duplicates-from-sorted-list
0141-linked-list-cycle
0142-linked-list-cycle-ii
0203-remove-linked-list-elements
0206-reverse-linked-list
0234-palindrome-linked-list
0237-delete-node-in-a-linked-list
0328-odd-even-linked-list
0908-middle-of-the-linked-list
2216-delete-the-middle-node-of-a-linked-list
2236-maximum-twin-sum-of-a-linked-list
2573-remove-nodes-from-linked-list

Counting

0169-majority-element
0229-majority-element-ii
1987-substrings-of-size-three-with-distinct-characters
2308-divide-array-into-equal-pairs

Heap (Priority Queue)

0948-sort-an-array

Merge Sort

0493-reverse-pairs
0948-sort-an-array

Bucket Sort

0948-sort-an-array

Radix Sort

0948-sort-an-array

Counting Sort

0561-array-partition
0948-sort-an-array

String Matching

0812-rotate-string

Tree

0094-binary-tree-inorder-traversal
0102-binary-tree-level-order-traversal
0103-binary-tree-zigzag-level-order-traversal
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0404-sum-of-left-leaves
2493-reverse-odd-levels-of-binary-tree

Depth-First Search

0094-binary-tree-inorder-traversal
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0404-sum-of-left-leaves
2493-reverse-odd-levels-of-binary-tree

Breadth-First Search

0102-binary-tree-level-order-traversal
0103-binary-tree-zigzag-level-order-traversal
0404-sum-of-left-leaves
2493-reverse-odd-levels-of-binary-tree

Binary Tree

0094-binary-tree-inorder-traversal
0102-binary-tree-level-order-traversal
0103-binary-tree-zigzag-level-order-traversal
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0404-sum-of-left-leaves
2493-reverse-odd-levels-of-binary-tree

Queue

3475-minimum-operations-to-make-binary-array-elements-equal-to-one-i

Sliding Window

0003-longest-substring-without-repeating-characters
0209-minimum-size-subarray-sum
0438-find-all-anagrams-in-a-string
0643-maximum-average-subarray-i
0713-subarray-product-less-than-k
0940-fruit-into-baskets
1046-max-consecutive-ones-iii
1370-count-number-of-nice-subarrays
1445-number-of-sub-arrays-of-size-k-and-average-greater-than-or-equal-to-threshold
1460-number-of-substrings-containing-all-three-characters
1755-defuse-the-bomb
1987-substrings-of-size-three-with-distinct-characters
2112-minimum-difference-between-highest-and-lowest-of-k-scores
2134-maximize-the-confusion-of-an-exam
2856-count-complete-subarrays-in-an-array
3475-minimum-operations-to-make-binary-array-elements-equal-to-one-i
3543-count-substrings-that-satisfy-k-constraint-i

Backtracking

1993-sum-of-all-subset-xor-totals

Combinatorics

0062-unique-paths
1993-sum-of-all-subset-xor-totals

Enumeration

1993-sum-of-all-subset-xor-totals

Binary Indexed Tree

0493-reverse-pairs

Segment Tree

0493-reverse-pairs

Ordered Set

0493-reverse-pairs

Union Find

0128-longest-consecutive-sequence