DSA-Leetcode

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
0015-3sum
0018-4sum
0026-remove-duplicates-from-sorted-array
0027-remove-element
0031-next-permutation
0033-search-in-rotated-sorted-array
0034-find-first-and-last-position-of-element-in-sorted-array
0035-search-insert-position
0036-valid-sudoku
0037-sudoku-solver
0039-combination-sum
0046-permutations
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
0081-search-in-rotated-sorted-array-ii
0088-merge-sorted-array
0118-pascals-triangle
0119-pascals-triangle-ii
0121-best-time-to-buy-and-sell-stock
0136-single-number
0152-maximum-product-subarray
0153-find-minimum-in-rotated-sorted-array
0162-find-peak-element
0169-majority-element
0189-rotate-array
0198-house-robber
0213-house-robber-ii
0217-contains-duplicate
0219-contains-duplicate-ii
0229-majority-element-ii
0238-product-of-array-except-self
0240-search-a-2d-matrix-ii
0322-coin-change
0410-split-array-largest-sum
0453-minimum-moves-to-equal-array-elements
0455-assign-cookies
0462-minimum-moves-to-equal-array-elements-ii
0493-reverse-pairs
0518-coin-change-ii
0540-single-element-in-a-sorted-array
0560-subarray-sum-equals-k
0561-array-partition
0605-can-place-flowers
0724-find-pivot-index
0733-flood-fill
0792-binary-search
0797-rabbits-in-forest
0890-lemonade-change
0907-koko-eating-bananas
0921-spiral-matrix-iii
1036-rotting-oranges
1046-max-consecutive-ones-iii
1056-capacity-to-ship-packages-within-d-days
1408-find-the-smallest-divisor-given-a-threshold
1421-find-numbers-with-even-number-of-digits
1468-check-if-n-and-its-double-exist
1524-string-matching-in-an-array
1603-running-sum-of-1d-array
1605-minimum-number-of-days-to-make-m-bouquets
1646-kth-missing-positive-number
1675-magnetic-force-between-two-balls
1791-richest-customer-wealth
1833-find-the-highest-altitude
1966-frequency-of-the-most-frequent-element
2035-count-sub-islands
2047-find-a-peak-element-ii
2102-find-the-middle-index-in-array
2231-find-first-palindromic-string-in-the-array
2271-rearrange-array-elements-by-sign
2552-maximum-sum-of-distinct-subarrays-with-length-k
2892-check-if-array-is-good
3094-minimum-number-of-operations-to-make-array-empty
3164-last-visited-integers
3165-find-indices-with-index-and-value-difference-i
3533-snake-in-matrix

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
0153-find-minimum-in-rotated-sorted-array
0162-find-peak-element
0240-search-a-2d-matrix-ii
0278-first-bad-version
0410-split-array-largest-sum
0493-reverse-pairs
0540-single-element-in-a-sorted-array
0792-binary-search
0907-koko-eating-bananas
1046-max-consecutive-ones-iii
1056-capacity-to-ship-packages-within-d-days
1408-find-the-smallest-divisor-given-a-threshold
1468-check-if-n-and-its-double-exist
1605-minimum-number-of-days-to-make-m-bouquets
1646-kth-missing-positive-number
1675-magnetic-force-between-two-balls
1966-frequency-of-the-most-frequent-element
2047-find-a-peak-element-ii

Divide and Conquer

0004-median-of-two-sorted-arrays
0053-maximum-subarray
0169-majority-element
0191-number-of-1-bits
0240-search-a-2d-matrix-ii
0493-reverse-pairs

Binary Indexed Tree

0493-reverse-pairs

Segment Tree

0493-reverse-pairs

Merge Sort

0493-reverse-pairs

Ordered Set

0493-reverse-pairs

Hash Table

0001-two-sum
0003-longest-substring-without-repeating-characters
0012-integer-to-roman
0013-roman-to-integer
0017-letter-combinations-of-a-phone-number
0036-valid-sudoku
0037-sudoku-solver
0049-group-anagrams
0073-set-matrix-zeroes
0141-linked-list-cycle
0169-majority-element
0217-contains-duplicate
0219-contains-duplicate-ii
0229-majority-element-ii
0242-valid-anagram
0299-bulls-and-cows
0424-longest-repeating-character-replacement
0451-sort-characters-by-frequency
0560-subarray-sum-equals-k
0797-rabbits-in-forest
1468-check-if-n-and-its-double-exist
1904-second-largest-digit-in-a-string
2552-maximum-sum-of-distinct-subarrays-with-length-k
2892-check-if-array-is-good
3094-minimum-number-of-operations-to-make-array-empty

String

0003-longest-substring-without-repeating-characters
0005-longest-palindromic-substring
0006-zigzag-conversion
0012-integer-to-roman
0013-roman-to-integer
0014-longest-common-prefix
0017-letter-combinations-of-a-phone-number
0020-valid-parentheses
0022-generate-parentheses
0028-find-the-index-of-the-first-occurrence-in-a-string
0038-count-and-say
0043-multiply-strings
0049-group-anagrams
0058-length-of-last-word
0067-add-binary
0072-edit-distance
0125-valid-palindrome
0151-reverse-words-in-a-string
0242-valid-anagram
0299-bulls-and-cows
0415-add-strings
0424-longest-repeating-character-replacement
0451-sort-characters-by-frequency
0521-longest-uncommon-subsequence-i
0541-reverse-string-ii
0551-student-attendance-record-i
0557-reverse-words-in-a-string-iii
0812-rotate-string
0874-backspace-string-compare
1078-remove-outermost-parentheses
1146-greatest-common-divisor-of-strings
1250-longest-common-subsequence
1524-string-matching-in-an-array
1894-merge-strings-alternately
1904-second-largest-digit-in-a-string
2173-number-of-valid-words-in-a-sentence
2231-find-first-palindromic-string-in-the-array
2373-apply-discount-to-prices
2572-append-characters-to-string-to-make-subsequence
2887-sort-vowels-in-a-string
3379-score-of-a-string
3533-snake-in-matrix

Sliding Window

0003-longest-substring-without-repeating-characters
0219-contains-duplicate-ii
0424-longest-repeating-character-replacement
1046-max-consecutive-ones-iii
1966-frequency-of-the-most-frequent-element
2552-maximum-sum-of-distinct-subarrays-with-length-k

Linked List

0002-add-two-numbers
0019-remove-nth-node-from-end-of-list
0021-merge-two-sorted-lists
0141-linked-list-cycle
0908-middle-of-the-linked-list
2216-delete-the-middle-node-of-a-linked-list

Math

0002-add-two-numbers
0007-reverse-integer
0009-palindrome-number
0012-integer-to-roman
0013-roman-to-integer
0043-multiply-strings
0048-rotate-image
0050-powx-n
0062-unique-paths
0066-plus-one
0067-add-binary
0069-sqrtx
0070-climbing-stairs
0189-rotate-array
0258-add-digits
0415-add-strings
0453-minimum-moves-to-equal-array-elements
0462-minimum-moves-to-equal-array-elements-ii
0797-rabbits-in-forest
1013-fibonacci-number
1146-greatest-common-divisor-of-strings
1421-find-numbers-with-even-number-of-digits
3172-divisible-and-non-divisible-sums-difference

Recursion

0002-add-two-numbers
0021-merge-two-sorted-lists
0050-powx-n
1013-fibonacci-number

Two Pointers

0005-longest-palindromic-substring
0011-container-with-most-water
0015-3sum
0018-4sum
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
0031-next-permutation
0075-sort-colors
0088-merge-sorted-array
0125-valid-palindrome
0141-linked-list-cycle
0151-reverse-words-in-a-string
0189-rotate-array
0455-assign-cookies
0541-reverse-string-ii
0557-reverse-words-in-a-string-iii
0874-backspace-string-compare
0908-middle-of-the-linked-list
1468-check-if-n-and-its-double-exist
1894-merge-strings-alternately
2216-delete-the-middle-node-of-a-linked-list
2231-find-first-palindromic-string-in-the-array
2271-rearrange-array-elements-by-sign
2572-append-characters-to-string-to-make-subsequence
3165-find-indices-with-index-and-value-difference-i

Dynamic Programming

0005-longest-palindromic-substring
0022-generate-parentheses
0053-maximum-subarray
0055-jump-game
0062-unique-paths
0063-unique-paths-ii
0064-minimum-path-sum
0070-climbing-stairs
0072-edit-distance
0118-pascals-triangle
0119-pascals-triangle-ii
0121-best-time-to-buy-and-sell-stock
0152-maximum-product-subarray
0198-house-robber
0213-house-robber-ii
0322-coin-change
0410-split-array-largest-sum
0518-coin-change-ii
1013-fibonacci-number
1250-longest-common-subsequence

Greedy

0011-container-with-most-water
0055-jump-game
0410-split-array-largest-sum
0455-assign-cookies
0561-array-partition
0605-can-place-flowers
0797-rabbits-in-forest
0890-lemonade-change
1966-frequency-of-the-most-frequent-element
2572-append-characters-to-string-to-make-subsequence
3094-minimum-number-of-operations-to-make-array-empty

Trie

0014-longest-common-prefix

Sorting

0015-3sum
0018-4sum
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
0451-sort-characters-by-frequency
0455-assign-cookies
0462-minimum-moves-to-equal-array-elements-ii
0561-array-partition
1468-check-if-n-and-its-double-exist
1675-magnetic-force-between-two-balls
1966-frequency-of-the-most-frequent-element
2887-sort-vowels-in-a-string
2892-check-if-array-is-good

Stack

0020-valid-parentheses
0094-binary-tree-inorder-traversal
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0874-backspace-string-compare
1078-remove-outermost-parentheses

Backtracking

0017-letter-combinations-of-a-phone-number
0022-generate-parentheses
0037-sudoku-solver
0039-combination-sum
0046-permutations
0078-subsets

String Matching

0028-find-the-index-of-the-first-occurrence-in-a-string
0812-rotate-string
1524-string-matching-in-an-array

Matrix

0036-valid-sudoku
0037-sudoku-solver
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
0240-search-a-2d-matrix-ii
0733-flood-fill
0921-spiral-matrix-iii
1036-rotting-oranges
1791-richest-customer-wealth
2035-count-sub-islands
2047-find-a-peak-element-ii

Simulation

0043-multiply-strings
0054-spiral-matrix
0059-spiral-matrix-ii
0067-add-binary
0258-add-digits
0415-add-strings
0874-backspace-string-compare
0921-spiral-matrix-iii
2271-rearrange-array-elements-by-sign
3164-last-visited-integers
3533-snake-in-matrix

Combinatorics

0062-unique-paths

Bit Manipulation

0067-add-binary
0078-subsets
0136-single-number
0191-number-of-1-bits

Memoization

0070-climbing-stairs
1013-fibonacci-number

Tree

0094-binary-tree-inorder-traversal
0100-same-tree
0104-maximum-depth-of-binary-tree
0110-balanced-binary-tree
0112-path-sum
0129-sum-root-to-leaf-numbers
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0236-lowest-common-ancestor-of-a-binary-tree
0783-search-in-a-binary-search-tree

Depth-First Search

0094-binary-tree-inorder-traversal
0100-same-tree
0104-maximum-depth-of-binary-tree
0110-balanced-binary-tree
0112-path-sum
0129-sum-root-to-leaf-numbers
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0236-lowest-common-ancestor-of-a-binary-tree
0547-number-of-provinces
0733-flood-fill
2035-count-sub-islands

Binary Tree

0094-binary-tree-inorder-traversal
0100-same-tree
0104-maximum-depth-of-binary-tree
0110-balanced-binary-tree
0112-path-sum
0129-sum-root-to-leaf-numbers
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0236-lowest-common-ancestor-of-a-binary-tree
0783-search-in-a-binary-search-tree

Breadth-First Search

0100-same-tree
0104-maximum-depth-of-binary-tree
0112-path-sum
0322-coin-change
0547-number-of-provinces
0733-flood-fill
1036-rotting-oranges
2035-count-sub-islands

Counting

0169-majority-element
0229-majority-element-ii
0299-bulls-and-cows
0451-sort-characters-by-frequency
3094-minimum-number-of-operations-to-make-array-empty

Prefix Sum

0238-product-of-array-except-self
0410-split-array-largest-sum
0560-subarray-sum-equals-k
0724-find-pivot-index
1046-max-consecutive-ones-iii
1603-running-sum-of-1d-array
1833-find-the-highest-altitude
1966-frequency-of-the-most-frequent-element
2102-find-the-middle-index-in-array

Number Theory

0258-add-digits

Interactive

0278-first-bad-version

Heap (Priority Queue)

0451-sort-characters-by-frequency

Bucket Sort

0451-sort-characters-by-frequency

Union Find

0547-number-of-provinces
2035-count-sub-islands

Graph

0547-number-of-provinces

Counting Sort

0561-array-partition

Binary Search Tree

0783-search-in-a-binary-search-tree