LEET-AND-FUN

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

LeetCode Topics

Math

0002-add-two-numbers
0009-palindrome-number
0013-roman-to-integer
0048-rotate-image
0062-unique-paths
0066-plus-one
0069-sqrtx
0070-climbing-stairs
0168-excel-sheet-column-title
0171-excel-sheet-column-number
0172-factorial-trailing-zeroes
0189-rotate-array
0204-count-primes
0231-power-of-two
0258-add-digits
0263-ugly-number
0268-missing-number
0292-nim-game
0326-power-of-three
0342-power-of-four
0367-valid-perfect-square
0412-fizz-buzz
0441-arranging-coins
0445-add-two-numbers-ii
0504-base-7
0507-perfect-number
0539-minimum-time-difference
0593-valid-square
0670-maximum-swap
1013-fibonacci-number
1236-n-th-tribonacci-number
1889-check-if-number-is-a-sum-of-powers-of-three
2083-three-divisors
2106-find-greatest-common-divisor-of-array
2284-smallest-value-of-the-rearranged-number
2383-add-two-integers
2481-strictly-palindromic-number
2491-smallest-even-multiple
2575-minimum-cuts-to-divide-a-circle
2680-count-collisions-of-monkeys-on-a-polygon
2752-sum-multiples
2824-check-if-the-number-is-fascinating
3371-harshad-number
3555-final-array-state-after-k-multiplication-operations-i

Greedy

0011-container-with-most-water
0045-jump-game-ii
0055-jump-game
0179-largest-number
0334-increasing-triplet-subsequence
0624-maximum-distance-in-arrays
0670-maximum-swap
0890-lemonade-change

Linked List

0002-add-two-numbers
0019-remove-nth-node-from-end-of-list
0021-merge-two-sorted-lists
0024-swap-nodes-in-pairs
0061-rotate-list
0141-linked-list-cycle
0142-linked-list-cycle-ii
0206-reverse-linked-list
0234-palindrome-linked-list
0328-odd-even-linked-list
0445-add-two-numbers-ii
0528-swapping-nodes-in-a-linked-list
0908-middle-of-the-linked-list
2216-delete-the-middle-node-of-a-linked-list

Stack

0020-valid-parentheses
0042-trapping-rain-water
0094-binary-tree-inorder-traversal
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0225-implement-stack-using-queues
0232-implement-queue-using-stacks
0234-palindrome-linked-list
0394-decode-string
0445-add-two-numbers-ii
0496-next-greater-element-i
0735-asteroid-collision
0739-daily-temperatures
2470-removing-stars-from-a-string

Recursion

0002-add-two-numbers
0021-merge-two-sorted-lists
0024-swap-nodes-in-pairs
0206-reverse-linked-list
0231-power-of-two
0234-palindrome-linked-list
0326-power-of-three
0342-power-of-four
0394-decode-string
1013-fibonacci-number
2680-count-collisions-of-monkeys-on-a-polygon

Array

0001-two-sum
0011-container-with-most-water
0015-3sum
0026-remove-duplicates-from-sorted-array
0027-remove-element
0033-search-in-rotated-sorted-array
0034-find-first-and-last-position-of-element-in-sorted-array
0036-valid-sudoku
0042-trapping-rain-water
0045-jump-game-ii
0048-rotate-image
0049-group-anagrams
0053-maximum-subarray
0054-spiral-matrix
0055-jump-game
0056-merge-intervals
0059-spiral-matrix-ii
0063-unique-paths-ii
0064-minimum-path-sum
0066-plus-one
0073-set-matrix-zeroes
0074-search-a-2d-matrix
0075-sort-colors
0078-subsets
0090-subsets-ii
0118-pascals-triangle
0120-triangle
0121-best-time-to-buy-and-sell-stock
0136-single-number
0153-find-minimum-in-rotated-sorted-array
0164-maximum-gap
0169-majority-element
0179-largest-number
0189-rotate-array
0198-house-robber
0200-number-of-islands
0204-count-primes
0213-house-robber-ii
0217-contains-duplicate
0238-product-of-array-except-self
0260-single-number-iii
0268-missing-number
0283-move-zeroes
0287-find-the-duplicate-number
0334-increasing-triplet-subsequence
0347-top-k-frequent-elements
0414-third-maximum-number
0419-battleships-in-a-board
0442-find-all-duplicates-in-an-array
0463-island-perimeter
0485-max-consecutive-ones
0496-next-greater-element-i
0529-minesweeper
0539-minimum-time-difference
0624-maximum-distance-in-arrays
0643-maximum-average-subarray-i
0645-set-mismatch
0695-max-area-of-island
0724-find-pivot-index
0733-flood-fill
0735-asteroid-collision
0739-daily-temperatures
0792-binary-search
0890-lemonade-change
0898-transpose-matrix
0906-walking-robot-simulation
0932-monotonic-array
0948-sort-an-array
1036-rotting-oranges
1046-max-consecutive-ones-iii
1256-rank-transform-of-an-array
1319-unique-number-of-occurrences
1620-check-if-array-pairs-are-divisible-by-k
1677-matrix-diagonal-sum
1694-make-sum-divisible-by-p
1798-max-number-of-k-sum-pairs
1833-find-the-highest-altitude
2006-find-the-student-that-will-replace-the-chalk
2038-nearest-exit-from-entrance-in-maze
2048-build-array-from-permutation
2058-concatenation-of-array
2106-find-greatest-common-divisor-of-array
2132-convert-1d-array-into-2d-array
2428-equal-row-and-column-pairs
2581-divide-players-into-teams-of-equal-skill
3429-special-array-i
3471-minimum-average-of-smallest-and-largest-elements
3555-final-array-state-after-k-multiplication-operations-i

Matrix

0036-valid-sudoku
0048-rotate-image
0054-spiral-matrix
0059-spiral-matrix-ii
0063-unique-paths-ii
0064-minimum-path-sum
0073-set-matrix-zeroes
0074-search-a-2d-matrix
0200-number-of-islands
0419-battleships-in-a-board
0463-island-perimeter
0529-minesweeper
0695-max-area-of-island
0733-flood-fill
0898-transpose-matrix
1036-rotting-oranges
1677-matrix-diagonal-sum
2038-nearest-exit-from-entrance-in-maze
2132-convert-1d-array-into-2d-array
2428-equal-row-and-column-pairs

Tree

0094-binary-tree-inorder-traversal
0100-same-tree
0101-symmetric-tree
0102-binary-tree-level-order-traversal
0104-maximum-depth-of-binary-tree
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0199-binary-tree-right-side-view
0226-invert-binary-tree
0404-sum-of-left-leaves
0450-delete-node-in-a-bst
0783-search-in-a-binary-search-tree
0784-insert-into-a-binary-search-tree
1116-maximum-level-sum-of-a-binary-tree

Binary Search Tree

0033-search-in-rotated-sorted-array
0034-find-first-and-last-position-of-element-in-sorted-array
0069-sqrtx
0074-search-a-2d-matrix
0153-find-minimum-in-rotated-sorted-array
0268-missing-number
0287-find-the-duplicate-number
0367-valid-perfect-square
0374-guess-number-higher-or-lower
0441-arranging-coins
0450-delete-node-in-a-bst
0783-search-in-a-binary-search-tree
0784-insert-into-a-binary-search-tree
0792-binary-search
1046-max-consecutive-ones-iii
2006-find-the-student-that-will-replace-the-chalk

Binary Tree

0094-binary-tree-inorder-traversal
0100-same-tree
0101-symmetric-tree
0102-binary-tree-level-order-traversal
0104-maximum-depth-of-binary-tree
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0199-binary-tree-right-side-view
0226-invert-binary-tree
0404-sum-of-left-leaves
0450-delete-node-in-a-bst
0783-search-in-a-binary-search-tree
0784-insert-into-a-binary-search-tree
1116-maximum-level-sum-of-a-binary-tree

Two Pointers

0005-longest-palindromic-substring
0011-container-with-most-water
0015-3sum
0019-remove-nth-node-from-end-of-list
0026-remove-duplicates-from-sorted-array
0027-remove-element
0028-find-the-index-of-the-first-occurrence-in-a-string
0042-trapping-rain-water
0061-rotate-list
0075-sort-colors
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
0392-is-subsequence
0443-string-compression
0528-swapping-nodes-in-a-linked-list
0908-middle-of-the-linked-list
1798-max-number-of-k-sum-pairs
1894-merge-strings-alternately
2216-delete-the-middle-node-of-a-linked-list
2481-strictly-palindromic-number
2581-divide-players-into-teams-of-equal-skill
3471-minimum-average-of-smallest-and-largest-elements

Brainteaser

0292-nim-game
2481-strictly-palindromic-number

Breadth-First Search

0100-same-tree
0101-symmetric-tree
0102-binary-tree-level-order-traversal
0104-maximum-depth-of-binary-tree
0199-binary-tree-right-side-view
0200-number-of-islands
0226-invert-binary-tree
0404-sum-of-left-leaves
0463-island-perimeter
0529-minesweeper
0695-max-area-of-island
0733-flood-fill
1036-rotting-oranges
1116-maximum-level-sum-of-a-binary-tree
2038-nearest-exit-from-entrance-in-maze

String

0003-longest-substring-without-repeating-characters
0005-longest-palindromic-substring
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
0125-valid-palindrome
0151-reverse-words-in-a-string
0168-excel-sheet-column-title
0171-excel-sheet-column-number
0179-largest-number
0205-isomorphic-strings
0242-valid-anagram
0344-reverse-string
0392-is-subsequence
0394-decode-string
0412-fizz-buzz
0443-string-compression
0539-minimum-time-difference
0657-robot-return-to-origin
0692-top-k-frequent-words
0812-rotate-string
1567-maximum-number-of-vowels-in-a-substring-of-given-length
1619-path-crossing
1894-merge-strings-alternately
2076-sum-of-digits-of-string-after-convert
2391-strong-password-checker-ii
2470-removing-stars-from-a-string
2492-length-of-the-longest-alphabetical-continuous-substring

Bit Manipulation

0078-subsets
0090-subsets-ii
0136-single-number
0201-bitwise-and-of-numbers-range
0231-power-of-two
0260-single-number-iii
0268-missing-number
0287-find-the-duplicate-number
0338-counting-bits
0342-power-of-four
0476-number-complement
0645-set-mismatch

Hash Table

0001-two-sum
0003-longest-substring-without-repeating-characters
0013-roman-to-integer
0036-valid-sudoku
0049-group-anagrams
0073-set-matrix-zeroes
0141-linked-list-cycle
0142-linked-list-cycle-ii
0169-majority-element
0205-isomorphic-strings
0217-contains-duplicate
0242-valid-anagram
0268-missing-number
0347-top-k-frequent-elements
0442-find-all-duplicates-in-an-array
0496-next-greater-element-i
0645-set-mismatch
0692-top-k-frequent-words
0906-walking-robot-simulation
1256-rank-transform-of-an-array
1319-unique-number-of-occurrences
1619-path-crossing
1620-check-if-array-pairs-are-divisible-by-k
1694-make-sum-divisible-by-p
1798-max-number-of-k-sum-pairs
2428-equal-row-and-column-pairs
2581-divide-players-into-teams-of-equal-skill
2824-check-if-the-number-is-fascinating

Trie

0014-longest-common-prefix
0386-lexicographical-numbers
0692-top-k-frequent-words

Sorting

0015-3sum
0049-group-anagrams
0056-merge-intervals
0075-sort-colors
0164-maximum-gap
0169-majority-element
0179-largest-number
0217-contains-duplicate
0242-valid-anagram
0268-missing-number
0347-top-k-frequent-elements
0414-third-maximum-number
0539-minimum-time-difference
0645-set-mismatch
0692-top-k-frequent-words
0948-sort-an-array
1256-rank-transform-of-an-array
1798-max-number-of-k-sum-pairs
2284-smallest-value-of-the-rearranged-number
2581-divide-players-into-teams-of-equal-skill
3471-minimum-average-of-smallest-and-largest-elements

Heap (Priority Queue)

0347-top-k-frequent-elements
0692-top-k-frequent-words
0948-sort-an-array
3555-final-array-state-after-k-multiplication-operations-i

Bucket Sort

0164-maximum-gap
0347-top-k-frequent-elements
0692-top-k-frequent-words
0948-sort-an-array

Counting

0169-majority-element
0347-top-k-frequent-elements
0692-top-k-frequent-words
1620-check-if-array-pairs-are-divisible-by-k

Divide and Conquer

0053-maximum-subarray
0169-majority-element
0347-top-k-frequent-elements
0948-sort-an-array

Quickselect

0347-top-k-frequent-elements

Geometry

0593-valid-square
2575-minimum-cuts-to-divide-a-circle

Radix Sort

0164-maximum-gap
0948-sort-an-array

Enumeration

0204-count-primes
2083-three-divisors

Number Theory

0204-count-primes
0258-add-digits
2083-three-divisors
2106-find-greatest-common-divisor-of-array
2491-smallest-even-multiple

Dynamic Programming

0005-longest-palindromic-substring
0042-trapping-rain-water
0045-jump-game-ii
0053-maximum-subarray
0055-jump-game
0062-unique-paths
0063-unique-paths-ii
0064-minimum-path-sum
0070-climbing-stairs
0118-pascals-triangle
0120-triangle
0121-best-time-to-buy-and-sell-stock
0198-house-robber
0213-house-robber-ii
0338-counting-bits
0392-is-subsequence
1013-fibonacci-number
1236-n-th-tribonacci-number

Database

0175-combine-two-tables
0176-second-highest-salary
0177-nth-highest-salary
0181-employees-earning-more-than-their-managers
0182-duplicate-emails

Backtracking

0078-subsets
0090-subsets-ii

Prefix Sum

0238-product-of-array-except-self
0724-find-pivot-index
1046-max-consecutive-ones-iii
1694-make-sum-divisible-by-p
1833-find-the-highest-altitude
2006-find-the-student-that-will-replace-the-chalk

Sliding Window

0003-longest-substring-without-repeating-characters
0643-maximum-average-subarray-i
1046-max-consecutive-ones-iii
1567-maximum-number-of-vowels-in-a-substring-of-given-length

Monotonic Stack

0042-trapping-rain-water
0496-next-greater-element-i
0739-daily-temperatures

Depth-First Search

0094-binary-tree-inorder-traversal
0100-same-tree
0101-symmetric-tree
0104-maximum-depth-of-binary-tree
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0199-binary-tree-right-side-view
0200-number-of-islands
0226-invert-binary-tree
0386-lexicographical-numbers
0404-sum-of-left-leaves
0419-battleships-in-a-board
0463-island-perimeter
0529-minesweeper
0695-max-area-of-island
0733-flood-fill
1116-maximum-level-sum-of-a-binary-tree

Simulation

0054-spiral-matrix
0059-spiral-matrix-ii
0258-add-digits
0412-fizz-buzz
0657-robot-return-to-origin
0735-asteroid-collision
0898-transpose-matrix
0906-walking-robot-simulation
2006-find-the-student-that-will-replace-the-chalk
2048-build-array-from-permutation
2058-concatenation-of-array
2076-sum-of-digits-of-string-after-convert
2132-convert-1d-array-into-2d-array
2428-equal-row-and-column-pairs
2470-removing-stars-from-a-string
3555-final-array-state-after-k-multiplication-operations-i

Game Theory

0292-nim-game

Memoization

0070-climbing-stairs
1013-fibonacci-number
1236-n-th-tribonacci-number

String Matching

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

Merge Sort

0948-sort-an-array

Counting Sort

0948-sort-an-array

Combinatorics

0062-unique-paths

Design

0225-implement-stack-using-queues
0232-implement-queue-using-stacks

Queue

0225-implement-stack-using-queues
0232-implement-queue-using-stacks

Union Find

0200-number-of-islands
0695-max-area-of-island

Interactive

0374-guess-number-higher-or-lower