All_Solved_LeetCode_Problems

A 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
0014-longest-common-prefix
0015-3sum
0016-3sum-closest
0026-remove-duplicates-from-sorted-array
0033-search-in-rotated-sorted-array
0034-find-first-and-last-position-of-element-in-sorted-array
0035-search-insert-position
0039-combination-sum
0042-trapping-rain-water
0046-permutations
0049-group-anagrams
0053-maximum-subarray
0054-spiral-matrix
0073-set-matrix-zeroes
0074-search-a-2d-matrix
0075-sort-colors
0078-subsets
0081-search-in-rotated-sorted-array-ii
0084-largest-rectangle-in-histogram
0088-merge-sorted-array
0090-subsets-ii
0108-convert-sorted-array-to-binary-search-tree
0121-best-time-to-buy-and-sell-stock
0136-single-number
0150-evaluate-reverse-polish-notation
0152-maximum-product-subarray
0162-find-peak-element
0167-two-sum-ii-input-array-is-sorted
0169-majority-element
0170-two-sum-iii-data-structure-design
0189-rotate-array
0200-number-of-islands
0209-minimum-size-subarray-sum
0215-kth-largest-element-in-an-array
0217-contains-duplicate
0238-product-of-array-except-self
0259-3sum-smaller
0268-missing-number
0283-move-zeroes
0287-find-the-duplicate-number
0303-range-sum-query-immutable
0347-top-k-frequent-elements
0349-intersection-of-two-arrays
0442-find-all-duplicates-in-an-array
0448-find-all-numbers-disappeared-in-an-array
0485-max-consecutive-ones
0496-next-greater-element-i
0523-continuous-subarray-sum
0540-single-element-in-a-sorted-array
0560-subarray-sum-equals-k
0605-can-place-flowers
0643-maximum-average-subarray-i
0645-set-mismatch
0682-baseball-game
0724-find-pivot-index
0733-flood-fill
0739-daily-temperatures
0744-find-smallest-letter-greater-than-target
0792-binary-search
0853-car-fleet
0904-fruit-into-baskets
0924-fair-candy-swap
0930-binary-subarrays-with-sum
0974-subarray-sums-divisible-by-k
0977-squares-of-a-sorted-array
0994-rotting-oranges
1004-max-consecutive-ones-iii
1051-height-checker
1056-capacity-to-ship-packages-within-d-days
1064-fixed-point
1099-two-sum-less-than-k
1186-maximum-subarray-sum-with-one-deletion
1207-unique-number-of-occurrences
1365-how-many-numbers-are-smaller-than-the-current-number
1470-shuffle-the-array
1476-count-negative-numbers-in-a-sorted-matrix
1528-kids-with-the-greatest-number-of-candies
1570-final-prices-with-a-special-discount-in-a-shop
1631-path-with-minimum-effort
1646-kth-missing-positive-number
1679-max-number-of-k-sum-pairs
1693-sum-of-all-odd-length-subarrays
1749-maximum-absolute-sum-of-any-subarray
1878-check-if-array-is-sorted-and-rotated
1929-concatenation-of-array
2047-find-a-peak-element-ii
2154-keep-multiplying-found-values-by-two
2210-find-target-indices-after-sorting-array
2271-rearrange-array-elements-by-sign
2465-number-of-distinct-averages
2502-sort-the-people
2540-minimum-common-value
2562-find-the-array-concatenation-value
2570-merge-two-2d-arrays-by-summing-values
2737-row-with-maximum-ones
2824-count-pairs-whose-sum-is-less-than-target
3010-divide-an-array-into-subarrays-with-minimum-cost-i

Two Pointers

0011-container-with-most-water
0015-3sum
0016-3sum-closest
0019-remove-nth-node-from-end-of-list
0026-remove-duplicates-from-sorted-array
0028-find-the-index-of-the-first-occurrence-in-a-string
0042-trapping-rain-water
0075-sort-colors
0088-merge-sorted-array
0125-valid-palindrome
0141-linked-list-cycle
0142-linked-list-cycle-ii
0167-two-sum-ii-input-array-is-sorted
0170-two-sum-iii-data-structure-design
0189-rotate-array
0202-happy-number
0234-palindrome-linked-list
0259-3sum-smaller
0283-move-zeroes
0287-find-the-duplicate-number
0344-reverse-string
0345-reverse-vowels-of-a-string
0349-intersection-of-two-arrays
0557-reverse-words-in-a-string-iii
0908-middle-of-the-linked-list
0977-squares-of-a-sorted-array
1099-two-sum-less-than-k
1679-max-number-of-k-sum-pairs
1894-merge-strings-alternately
2216-delete-the-middle-node-of-a-linked-list
2271-rearrange-array-elements-by-sign
2465-number-of-distinct-averages
2540-minimum-common-value
2562-find-the-array-concatenation-value
2570-merge-two-2d-arrays-by-summing-values
2824-count-pairs-whose-sum-is-less-than-target
3794-reverse-string-prefix
3823-reverse-letters-then-special-characters-in-a-string

Sorting

0015-3sum
0016-3sum-closest
0049-group-anagrams
0075-sort-colors
0088-merge-sorted-array
0169-majority-element
0215-kth-largest-element-in-an-array
0217-contains-duplicate
0242-valid-anagram
0259-3sum-smaller
0268-missing-number
0347-top-k-frequent-elements
0349-intersection-of-two-arrays
0389-find-the-difference
0442-find-all-duplicates-in-an-array
0645-set-mismatch
0853-car-fleet
0924-fair-candy-swap
0977-squares-of-a-sorted-array
1051-height-checker
1099-two-sum-less-than-k
1365-how-many-numbers-are-smaller-than-the-current-number
1679-max-number-of-k-sum-pairs
2154-keep-multiplying-found-values-by-two
2210-find-target-indices-after-sorting-array
2465-number-of-distinct-averages
2502-sort-the-people
2824-count-pairs-whose-sum-is-less-than-target
3010-divide-an-array-into-subarrays-with-minimum-cost-i
3536-maximum-product-of-two-digits

Math

0013-roman-to-integer
0069-sqrtx
0150-evaluate-reverse-polish-notation
0189-rotate-array
0202-happy-number
0268-missing-number
0326-power-of-three
0367-valid-perfect-square
0412-fizz-buzz
0523-continuous-subarray-sum
1518-water-bottles
1693-sum-of-all-odd-length-subarrays
2032-largest-odd-number-in-string
2383-add-two-integers
2608-count-the-digits-that-divide-a-number
3536-maximum-product-of-two-digits

Hash Table

0001-two-sum
0003-longest-substring-without-repeating-characters
0013-roman-to-integer
0049-group-anagrams
0073-set-matrix-zeroes
0076-minimum-window-substring
0138-copy-list-with-random-pointer
0141-linked-list-cycle
0142-linked-list-cycle-ii
0169-majority-element
0170-two-sum-iii-data-structure-design
0202-happy-number
0205-isomorphic-strings
0217-contains-duplicate
0242-valid-anagram
0268-missing-number
0340-longest-substring-with-at-most-k-distinct-characters
0347-top-k-frequent-elements
0349-intersection-of-two-arrays
0387-first-unique-character-in-a-string
0389-find-the-difference
0424-longest-repeating-character-replacement
0438-find-all-anagrams-in-a-string
0442-find-all-duplicates-in-an-array
0448-find-all-numbers-disappeared-in-an-array
0496-next-greater-element-i
0523-continuous-subarray-sum
0560-subarray-sum-equals-k
0645-set-mismatch
0904-fruit-into-baskets
0924-fair-candy-swap
0930-binary-subarrays-with-sum
0974-subarray-sums-divisible-by-k
1207-unique-number-of-occurrences
1365-how-many-numbers-are-smaller-than-the-current-number
1679-max-number-of-k-sum-pairs
1890-sum-of-beauty-of-all-substrings
1987-substrings-of-size-three-with-distinct-characters
2154-keep-multiplying-found-values-by-two
2351-first-letter-to-appear-twice
2465-number-of-distinct-averages
2502-sort-the-people
2540-minimum-common-value
2570-merge-two-2d-arrays-by-summing-values
3541-find-most-frequent-vowel-and-consonant

String

0003-longest-substring-without-repeating-characters
0013-roman-to-integer
0014-longest-common-prefix
0020-valid-parentheses
0028-find-the-index-of-the-first-occurrence-in-a-string
0049-group-anagrams
0058-length-of-last-word
0076-minimum-window-substring
0125-valid-palindrome
0205-isomorphic-strings
0242-valid-anagram
0257-binary-tree-paths
0340-longest-substring-with-at-most-k-distinct-characters
0344-reverse-string
0345-reverse-vowels-of-a-string
0387-first-unique-character-in-a-string
0389-find-the-difference
0412-fizz-buzz
0424-longest-repeating-character-replacement
0438-find-all-anagrams-in-a-string
0551-student-attendance-record-i
0557-reverse-words-in-a-string-iii
0812-rotate-string
1119-remove-vowels-from-a-string
1456-maximum-number-of-vowels-in-a-substring-of-given-length
1890-sum-of-beauty-of-all-substrings
1894-merge-strings-alternately
1987-substrings-of-size-three-with-distinct-characters
2032-largest-odd-number-in-string
2351-first-letter-to-appear-twice
2390-removing-stars-from-a-string
2502-sort-the-people
2710-remove-trailing-zeros-from-a-string
3447-clear-digits
3541-find-most-frequent-vowel-and-consonant
3794-reverse-string-prefix
3813-vowel-consonant-score
3823-reverse-letters-then-special-characters-in-a-string

Binary Search

0004-median-of-two-sorted-arrays
0033-search-in-rotated-sorted-array
0034-find-first-and-last-position-of-element-in-sorted-array
0035-search-insert-position
0069-sqrtx
0074-search-a-2d-matrix
0081-search-in-rotated-sorted-array-ii
0162-find-peak-element
0167-two-sum-ii-input-array-is-sorted
0209-minimum-size-subarray-sum
0259-3sum-smaller
0268-missing-number
0278-first-bad-version
0287-find-the-duplicate-number
0349-intersection-of-two-arrays
0367-valid-perfect-square
0374-guess-number-higher-or-lower
0540-single-element-in-a-sorted-array
0744-find-smallest-letter-greater-than-target
0792-binary-search
0924-fair-candy-swap
1004-max-consecutive-ones-iii
1056-capacity-to-ship-packages-within-d-days
1064-fixed-point
1099-two-sum-less-than-k
1476-count-negative-numbers-in-a-sorted-matrix
1631-path-with-minimum-effort
1646-kth-missing-positive-number
2047-find-a-peak-element-ii
2210-find-target-indices-after-sorting-array
2540-minimum-common-value
2824-count-pairs-whose-sum-is-less-than-target

Matrix

0054-spiral-matrix
0073-set-matrix-zeroes
0074-search-a-2d-matrix
0200-number-of-islands
0733-flood-fill
0994-rotting-oranges
1476-count-negative-numbers-in-a-sorted-matrix
1631-path-with-minimum-effort
2047-find-a-peak-element-ii
2737-row-with-maximum-ones

Bit Manipulation

0078-subsets
0090-subsets-ii
0136-single-number
0268-missing-number
0287-find-the-duplicate-number
0389-find-the-difference
0645-set-mismatch
2351-first-letter-to-appear-twice

Sliding Window

0003-longest-substring-without-repeating-characters
0076-minimum-window-substring
0209-minimum-size-subarray-sum
0340-longest-substring-with-at-most-k-distinct-characters
0424-longest-repeating-character-replacement
0438-find-all-anagrams-in-a-string
0643-maximum-average-subarray-i
0904-fruit-into-baskets
0930-binary-subarrays-with-sum
1004-max-consecutive-ones-iii
1456-maximum-number-of-vowels-in-a-substring-of-given-length
1987-substrings-of-size-three-with-distinct-characters

Counting

0169-majority-element
0347-top-k-frequent-elements
0387-first-unique-character-in-a-string
1890-sum-of-beauty-of-all-substrings
1987-substrings-of-size-three-with-distinct-characters
2351-first-letter-to-appear-twice
3541-find-most-frequent-vowel-and-consonant

String Matching

0028-find-the-index-of-the-first-occurrence-in-a-string
0812-rotate-string

Prefix Sum

0209-minimum-size-subarray-sum
0238-product-of-array-except-self
0303-range-sum-query-immutable
0523-continuous-subarray-sum
0560-subarray-sum-equals-k
0724-find-pivot-index
0930-binary-subarrays-with-sum
0974-subarray-sums-divisible-by-k
1004-max-consecutive-ones-iii
1693-sum-of-all-odd-length-subarrays

Divide and Conquer

0004-median-of-two-sorted-arrays
0053-maximum-subarray
0108-convert-sorted-array-to-binary-search-tree
0169-majority-element
0215-kth-largest-element-in-an-array
0347-top-k-frequent-elements

Dynamic Programming

0042-trapping-rain-water
0053-maximum-subarray
0121-best-time-to-buy-and-sell-stock
0152-maximum-product-subarray
1186-maximum-subarray-sum-with-one-deletion
1749-maximum-absolute-sum-of-any-subarray

Heap (Priority Queue)

0215-kth-largest-element-in-an-array
0347-top-k-frequent-elements
1631-path-with-minimum-effort

Bucket Sort

0347-top-k-frequent-elements

Quickselect

0215-kth-largest-element-in-an-array
0347-top-k-frequent-elements

Greedy

0011-container-with-most-water
0605-can-place-flowers
2032-largest-odd-number-in-string

Simulation

0054-spiral-matrix
0412-fizz-buzz
0682-baseball-game
1518-water-bottles
1929-concatenation-of-array
2154-keep-multiplying-found-values-by-two
2271-rearrange-array-elements-by-sign
2390-removing-stars-from-a-string
2562-find-the-array-concatenation-value
3447-clear-digits
3813-vowel-consonant-score
3823-reverse-letters-then-special-characters-in-a-string

Interactive

0278-first-bad-version
0374-guess-number-higher-or-lower

Linked List

0019-remove-nth-node-from-end-of-list
0021-merge-two-sorted-lists
0083-remove-duplicates-from-sorted-list
0138-copy-list-with-random-pointer
0141-linked-list-cycle
0142-linked-list-cycle-ii
0206-reverse-linked-list
0234-palindrome-linked-list
0237-delete-node-in-a-linked-list
0328-odd-even-linked-list
0838-design-linked-list
0908-middle-of-the-linked-list
2216-delete-the-middle-node-of-a-linked-list

Design

0155-min-stack
0170-two-sum-iii-data-structure-design
0303-range-sum-query-immutable
0838-design-linked-list
0937-online-stock-span

Recursion

0021-merge-two-sorted-lists
0206-reverse-linked-list
0234-palindrome-linked-list
0326-power-of-three

Stack

0020-valid-parentheses
0042-trapping-rain-water
0084-largest-rectangle-in-histogram
0094-binary-tree-inorder-traversal
0144-binary-tree-preorder-traversal
0150-evaluate-reverse-polish-notation
0155-min-stack
0234-palindrome-linked-list
0496-next-greater-element-i
0682-baseball-game
0739-daily-temperatures
0853-car-fleet
0937-online-stock-span
1570-final-prices-with-a-special-discount-in-a-shop
2390-removing-stars-from-a-string
3447-clear-digits

Monotonic Stack

0042-trapping-rain-water
0084-largest-rectangle-in-histogram
0496-next-greater-element-i
0739-daily-temperatures
0853-car-fleet
0937-online-stock-span
1570-final-prices-with-a-special-discount-in-a-shop

Database

0175-combine-two-tables
0176-second-highest-salary
0183-customers-who-never-order
0595-big-countries
0596-classes-with-at-least-5-students
1757-recyclable-and-low-fat-products

Data Stream

0170-two-sum-iii-data-structure-design
0937-online-stock-span

Trie

0014-longest-common-prefix

Queue

0387-first-unique-character-in-a-string

Tree

0094-binary-tree-inorder-traversal
0098-validate-binary-search-tree
0100-same-tree
0102-binary-tree-level-order-traversal
0103-binary-tree-zigzag-level-order-traversal
0104-maximum-depth-of-binary-tree
0108-convert-sorted-array-to-binary-search-tree
0110-balanced-binary-tree
0111-minimum-depth-of-binary-tree
0112-path-sum
0113-path-sum-ii
0144-binary-tree-preorder-traversal
0199-binary-tree-right-side-view
0226-invert-binary-tree
0236-lowest-common-ancestor-of-a-binary-tree
0257-binary-tree-paths
0543-diameter-of-binary-tree
0637-average-of-levels-in-binary-tree
0700-search-in-a-binary-search-tree

Depth-First Search

0094-binary-tree-inorder-traversal
0098-validate-binary-search-tree
0100-same-tree
0104-maximum-depth-of-binary-tree
0110-balanced-binary-tree
0111-minimum-depth-of-binary-tree
0112-path-sum
0113-path-sum-ii
0144-binary-tree-preorder-traversal
0199-binary-tree-right-side-view
0200-number-of-islands
0207-course-schedule
0210-course-schedule-ii
0226-invert-binary-tree
0236-lowest-common-ancestor-of-a-binary-tree
0257-binary-tree-paths
0543-diameter-of-binary-tree
0547-number-of-provinces
0637-average-of-levels-in-binary-tree
0733-flood-fill
0802-find-eventual-safe-states
1319-number-of-operations-to-make-network-connected
1466-reorder-routes-to-make-all-paths-lead-to-the-city-zero
1631-path-with-minimum-effort
1971-find-if-path-exists-in-graph
2360-longest-cycle-in-a-graph

Breadth-First Search

0100-same-tree
0102-binary-tree-level-order-traversal
0103-binary-tree-zigzag-level-order-traversal
0104-maximum-depth-of-binary-tree
0111-minimum-depth-of-binary-tree
0112-path-sum
0199-binary-tree-right-side-view
0200-number-of-islands
0207-course-schedule
0210-course-schedule-ii
0226-invert-binary-tree
0547-number-of-provinces
0637-average-of-levels-in-binary-tree
0733-flood-fill
0802-find-eventual-safe-states
0994-rotting-oranges
1197-minimum-knight-moves
1319-number-of-operations-to-make-network-connected
1466-reorder-routes-to-make-all-paths-lead-to-the-city-zero
1631-path-with-minimum-effort
1971-find-if-path-exists-in-graph
2360-longest-cycle-in-a-graph

Binary Tree

0094-binary-tree-inorder-traversal
0098-validate-binary-search-tree
0100-same-tree
0102-binary-tree-level-order-traversal
0103-binary-tree-zigzag-level-order-traversal
0104-maximum-depth-of-binary-tree
0108-convert-sorted-array-to-binary-search-tree
0110-balanced-binary-tree
0111-minimum-depth-of-binary-tree
0112-path-sum
0113-path-sum-ii
0144-binary-tree-preorder-traversal
0199-binary-tree-right-side-view
0226-invert-binary-tree
0236-lowest-common-ancestor-of-a-binary-tree
0257-binary-tree-paths
0543-diameter-of-binary-tree
0637-average-of-levels-in-binary-tree
0700-search-in-a-binary-search-tree

Binary Search Tree

0098-validate-binary-search-tree
0108-convert-sorted-array-to-binary-search-tree
0700-search-in-a-binary-search-tree

Backtracking

0039-combination-sum
0046-permutations
0078-subsets
0090-subsets-ii
0113-path-sum-ii
0257-binary-tree-paths

Counting Sort

1051-height-checker
1365-how-many-numbers-are-smaller-than-the-current-number

Enumeration

3010-divide-an-array-into-subarrays-with-minimum-cost-i

Union-Find

0200-number-of-islands
0547-number-of-provinces
1319-number-of-operations-to-make-network-connected
1631-path-with-minimum-effort
1971-find-if-path-exists-in-graph

Graph Theory

0207-course-schedule
0210-course-schedule-ii
0547-number-of-provinces
0802-find-eventual-safe-states
1319-number-of-operations-to-make-network-connected
1466-reorder-routes-to-make-all-paths-lead-to-the-city-zero
1971-find-if-path-exists-in-graph
2360-longest-cycle-in-a-graph

Topological Sort

0207-course-schedule
0210-course-schedule-ii
0802-find-eventual-safe-states
2360-longest-cycle-in-a-graph