leetcode-questions

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
0050-powx-n
0060-permutation-sequence
2965-find-missing-and-repeated-values

Array

0001-two-sum
0004-median-of-two-sorted-arrays
0014-longest-common-prefix
0015-3sum
0018-4sum
0026-remove-duplicates-from-sorted-array
0031-next-permutation
0033-search-in-rotated-sorted-array
0037-sudoku-solver
0039-combination-sum
0040-combination-sum-ii
0042-trapping-rain-water
0046-permutations
0048-rotate-image
0051-n-queens
0053-maximum-subarray
0056-merge-intervals
0073-set-matrix-zeroes
0074-search-a-2d-matrix
0075-sort-colors
0084-largest-rectangle-in-histogram
0088-merge-sorted-array
0090-subsets-ii
0105-construct-binary-tree-from-preorder-and-inorder-traversal
0106-construct-binary-tree-from-inorder-and-postorder-traversal
0108-convert-sorted-array-to-binary-search-tree
0121-best-time-to-buy-and-sell-stock
0128-longest-consecutive-sequence
0215-kth-largest-element-in-an-array
0229-majority-element-ii
0239-sliding-window-maximum
0287-find-the-duplicate-number
0322-coin-change
0347-top-k-frequent-elements
0455-assign-cookies
0485-max-consecutive-ones
0493-reverse-pairs
0496-next-greater-element-i
0733-flood-fill
0994-rotting-oranges
1008-construct-binary-search-tree-from-preorder-traversal
2965-find-missing-and-repeated-values

Two Pointers

0005-longest-palindromic-substring
0015-3sum
0018-4sum
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
0031-next-permutation
0042-trapping-rain-water
0061-rotate-list
0075-sort-colors
0088-merge-sorted-array
0141-linked-list-cycle
0142-linked-list-cycle-ii
0151-reverse-words-in-a-string
0160-intersection-of-two-linked-lists
0165-compare-version-numbers
0234-palindrome-linked-list
0287-find-the-duplicate-number
0295-find-median-from-data-stream
0455-assign-cookies
0653-two-sum-iv-input-is-a-bst
0876-middle-of-the-linked-list

Binary Search

0004-median-of-two-sorted-arrays
0033-search-in-rotated-sorted-array
0074-search-a-2d-matrix
0287-find-the-duplicate-number
0493-reverse-pairs

Bit Manipulation

0090-subsets-ii
0287-find-the-duplicate-number

Hash Table

0001-two-sum
0003-longest-substring-without-repeating-characters
0013-roman-to-integer
0037-sudoku-solver
0073-set-matrix-zeroes
0105-construct-binary-tree-from-preorder-and-inorder-traversal
0106-construct-binary-tree-from-inorder-and-postorder-traversal
0128-longest-consecutive-sequence
0133-clone-graph
0138-copy-list-with-random-pointer
0141-linked-list-cycle
0142-linked-list-cycle-ii
0160-intersection-of-two-linked-lists
0229-majority-element-ii
0347-top-k-frequent-elements
0460-lfu-cache
0496-next-greater-element-i
0653-two-sum-iv-input-is-a-bst
0987-vertical-order-traversal-of-a-binary-tree
2965-find-missing-and-repeated-values

Matrix

0037-sudoku-solver
0048-rotate-image
0073-set-matrix-zeroes
0074-search-a-2d-matrix
0733-flood-fill
0994-rotting-oranges
2965-find-missing-and-repeated-values

Recursion

0002-add-two-numbers
0021-merge-two-sorted-lists
0050-powx-n
0060-permutation-sequence
0206-reverse-linked-list
0234-palindrome-linked-list

Sorting

0015-3sum
0018-4sum
0056-merge-intervals
0075-sort-colors
0088-merge-sorted-array
0215-kth-largest-element-in-an-array
0229-majority-element-ii
0295-find-median-from-data-stream
0347-top-k-frequent-elements
0455-assign-cookies
0987-vertical-order-traversal-of-a-binary-tree

Dynamic Programming

0005-longest-palindromic-substring
0042-trapping-rain-water
0053-maximum-subarray
0121-best-time-to-buy-and-sell-stock
0124-binary-tree-maximum-path-sum
0322-coin-change
1312-minimum-insertion-steps-to-make-a-string-palindrome
1373-maximum-sum-bst-in-binary-tree

Divide and Conquer

0004-median-of-two-sorted-arrays
0053-maximum-subarray
0105-construct-binary-tree-from-preorder-and-inorder-traversal
0106-construct-binary-tree-from-inorder-and-postorder-traversal
0108-convert-sorted-array-to-binary-search-tree
0215-kth-largest-element-in-an-array
0347-top-k-frequent-elements
0493-reverse-pairs

Counting

0229-majority-element-ii
0347-top-k-frequent-elements

Binary Indexed Tree

0493-reverse-pairs

Segment Tree

0493-reverse-pairs

Merge Sort

0493-reverse-pairs

Ordered Set

0493-reverse-pairs

Union-Find

0128-longest-consecutive-sequence

String

0003-longest-substring-without-repeating-characters
0005-longest-palindromic-substring
0008-string-to-integer-atoi
0013-roman-to-integer
0014-longest-common-prefix
0020-valid-parentheses
0028-find-the-index-of-the-first-occurrence-in-a-string
0038-count-and-say
0151-reverse-words-in-a-string
0165-compare-version-numbers
0297-serialize-and-deserialize-binary-tree
0686-repeated-string-match
1312-minimum-insertion-steps-to-make-a-string-palindrome

Sliding Window

0003-longest-substring-without-repeating-characters
0239-sliding-window-maximum

Linked List

0002-add-two-numbers
0019-remove-nth-node-from-end-of-list
0021-merge-two-sorted-lists
0061-rotate-list
0114-flatten-binary-tree-to-linked-list
0116-populating-next-right-pointers-in-each-node
0138-copy-list-with-random-pointer
0141-linked-list-cycle
0142-linked-list-cycle-ii
0160-intersection-of-two-linked-lists
0206-reverse-linked-list
0234-palindrome-linked-list
0237-delete-node-in-a-linked-list
0460-lfu-cache
0876-middle-of-the-linked-list

Stack

0020-valid-parentheses
0042-trapping-rain-water
0084-largest-rectangle-in-histogram
0094-binary-tree-inorder-traversal
0114-flatten-binary-tree-to-linked-list
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0155-min-stack
0173-binary-search-tree-iterator
0225-implement-stack-using-queues
0234-palindrome-linked-list
0496-next-greater-element-i
0901-online-stock-span
1008-construct-binary-search-tree-from-preorder-traversal

Monotonic Stack

0042-trapping-rain-water
0084-largest-rectangle-in-histogram
0496-next-greater-element-i
0901-online-stock-span
1008-construct-binary-search-tree-from-preorder-traversal

Breadth-First Search

0100-same-tree
0101-symmetric-tree
0102-binary-tree-level-order-traversal
0103-binary-tree-zigzag-level-order-traversal
0104-maximum-depth-of-binary-tree
0116-populating-next-right-pointers-in-each-node
0133-clone-graph
0199-binary-tree-right-side-view
0207-course-schedule
0297-serialize-and-deserialize-binary-tree
0322-coin-change
0653-two-sum-iv-input-is-a-bst
0662-maximum-width-of-binary-tree
0733-flood-fill
0987-vertical-order-traversal-of-a-binary-tree
0994-rotting-oranges

Greedy

0455-assign-cookies

Backtracking

0037-sudoku-solver
0039-combination-sum
0040-combination-sum-ii
0046-permutations
0051-n-queens
0090-subsets-ii

Design

0155-min-stack
0173-binary-search-tree-iterator
0225-implement-stack-using-queues
0295-find-median-from-data-stream
0297-serialize-and-deserialize-binary-tree
0460-lfu-cache
0703-kth-largest-element-in-a-stream
0901-online-stock-span

Heap (Priority Queue)

0215-kth-largest-element-in-an-array
0239-sliding-window-maximum
0295-find-median-from-data-stream
0347-top-k-frequent-elements
0703-kth-largest-element-in-a-stream

Data Stream

0295-find-median-from-data-stream
0703-kth-largest-element-in-a-stream
0901-online-stock-span

Bucket Sort

0347-top-k-frequent-elements

Quickselect

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

Queue

0225-implement-stack-using-queues
0239-sliding-window-maximum

Doubly-Linked List

0460-lfu-cache

Monotonic Queue

0239-sliding-window-maximum

Trie

0014-longest-common-prefix

String Matching

0028-find-the-index-of-the-first-occurrence-in-a-string
0686-repeated-string-match

Tree

0094-binary-tree-inorder-traversal
0098-validate-binary-search-tree
0100-same-tree
0101-symmetric-tree
0102-binary-tree-level-order-traversal
0103-binary-tree-zigzag-level-order-traversal
0104-maximum-depth-of-binary-tree
0105-construct-binary-tree-from-preorder-and-inorder-traversal
0106-construct-binary-tree-from-inorder-and-postorder-traversal
0108-convert-sorted-array-to-binary-search-tree
0110-balanced-binary-tree
0114-flatten-binary-tree-to-linked-list
0116-populating-next-right-pointers-in-each-node
0124-binary-tree-maximum-path-sum
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0173-binary-search-tree-iterator
0199-binary-tree-right-side-view
0230-kth-smallest-element-in-a-bst
0235-lowest-common-ancestor-of-a-binary-search-tree
0236-lowest-common-ancestor-of-a-binary-tree
0297-serialize-and-deserialize-binary-tree
0543-diameter-of-binary-tree
0653-two-sum-iv-input-is-a-bst
0662-maximum-width-of-binary-tree
0700-search-in-a-binary-search-tree
0703-kth-largest-element-in-a-stream
0987-vertical-order-traversal-of-a-binary-tree
1008-construct-binary-search-tree-from-preorder-traversal
1373-maximum-sum-bst-in-binary-tree

Depth-First Search

0094-binary-tree-inorder-traversal
0098-validate-binary-search-tree
0100-same-tree
0101-symmetric-tree
0104-maximum-depth-of-binary-tree
0110-balanced-binary-tree
0114-flatten-binary-tree-to-linked-list
0116-populating-next-right-pointers-in-each-node
0124-binary-tree-maximum-path-sum
0133-clone-graph
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0199-binary-tree-right-side-view
0207-course-schedule
0230-kth-smallest-element-in-a-bst
0235-lowest-common-ancestor-of-a-binary-search-tree
0236-lowest-common-ancestor-of-a-binary-tree
0297-serialize-and-deserialize-binary-tree
0543-diameter-of-binary-tree
0653-two-sum-iv-input-is-a-bst
0662-maximum-width-of-binary-tree
0733-flood-fill
0987-vertical-order-traversal-of-a-binary-tree
1373-maximum-sum-bst-in-binary-tree

Binary Tree

0094-binary-tree-inorder-traversal
0098-validate-binary-search-tree
0100-same-tree
0101-symmetric-tree
0102-binary-tree-level-order-traversal
0103-binary-tree-zigzag-level-order-traversal
0104-maximum-depth-of-binary-tree
0105-construct-binary-tree-from-preorder-and-inorder-traversal
0106-construct-binary-tree-from-inorder-and-postorder-traversal
0108-convert-sorted-array-to-binary-search-tree
0110-balanced-binary-tree
0114-flatten-binary-tree-to-linked-list
0116-populating-next-right-pointers-in-each-node
0124-binary-tree-maximum-path-sum
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0173-binary-search-tree-iterator
0199-binary-tree-right-side-view
0230-kth-smallest-element-in-a-bst
0235-lowest-common-ancestor-of-a-binary-search-tree
0236-lowest-common-ancestor-of-a-binary-tree
0297-serialize-and-deserialize-binary-tree
0543-diameter-of-binary-tree
0653-two-sum-iv-input-is-a-bst
0662-maximum-width-of-binary-tree
0700-search-in-a-binary-search-tree
0703-kth-largest-element-in-a-stream
0987-vertical-order-traversal-of-a-binary-tree
1008-construct-binary-search-tree-from-preorder-traversal
1373-maximum-sum-bst-in-binary-tree

Binary Search Tree

0098-validate-binary-search-tree
0108-convert-sorted-array-to-binary-search-tree
0173-binary-search-tree-iterator
0230-kth-smallest-element-in-a-bst
0235-lowest-common-ancestor-of-a-binary-search-tree
0653-two-sum-iv-input-is-a-bst
0700-search-in-a-binary-search-tree
0703-kth-largest-element-in-a-stream
1008-construct-binary-search-tree-from-preorder-traversal
1373-maximum-sum-bst-in-binary-tree

Iterator

0173-binary-search-tree-iterator

Graph Theory

0133-clone-graph
0207-course-schedule

Topological Sort

0207-course-schedule