LeetCode

LeetCode Topics

Array

0001-two-sum
0011-container-with-most-water
0026-remove-duplicates-from-sorted-array
0027-remove-element
0035-search-insert-position
0039-combination-sum
0042-trapping-rain-water
0045-jump-game-ii
0046-permutations
0048-rotate-image
0053-maximum-subarray
0054-spiral-matrix
0055-jump-game
0059-spiral-matrix-ii
0066-plus-one
0073-set-matrix-zeroes
0074-search-a-2d-matrix
0075-sort-colors
0090-subsets-ii
0121-best-time-to-buy-and-sell-stock
0135-candy
0136-single-number
0204-count-primes
0217-contains-duplicate
0219-contains-duplicate-ii
0229-majority-element-ii
0238-product-of-array-except-self
0268-missing-number
0303-range-sum-query-immutable
0350-intersection-of-two-arrays-ii
0414-third-maximum-number
0448-find-all-numbers-disappeared-in-an-array
0485-max-consecutive-ones
0486-predict-the-winner
0498-diagonal-traverse
0566-reshape-the-matrix
0718-maximum-length-of-repeated-subarray
0735-asteroid-collision
0739-daily-temperatures
0792-binary-search
1127-last-stone-weight
1256-rank-transform-of-an-array
1310-watering-plants
1631-number-of-sub-arrays-with-odd-sum
1755-defuse-the-bomb
1786-count-the-number-of-consistent-strings
1849-maximum-absolute-sum-of-any-subarray
2113-find-the-kth-largest-integer-in-the-array
2148-minimum-number-of-moves-to-seat-everyone
2486-most-frequent-even-element
2503-longest-subarray-with-maximum-bitwise-and
2707-merge-two-2d-arrays-by-summing-values
2917-count-pairs-whose-sum-is-less-than-target

Hash Table

0001-two-sum
0073-set-matrix-zeroes
0187-repeated-dna-sequences
0205-isomorphic-strings
0217-contains-duplicate
0219-contains-duplicate-ii
0229-majority-element-ii
0268-missing-number
0350-intersection-of-two-arrays-ii
0387-first-unique-character-in-a-string
0389-find-the-difference
0398-random-pick-index
0409-longest-palindrome
0448-find-all-numbers-disappeared-in-an-array
0567-permutation-in-string
0920-uncommon-words-from-two-sentences
1256-rank-transform-of-an-array
1786-count-the-number-of-consistent-strings
1987-substrings-of-size-three-with-distinct-characters
2486-most-frequent-even-element
2707-merge-two-2d-arrays-by-summing-values

Sorting

0075-sort-colors
0217-contains-duplicate
0229-majority-element-ii
0268-missing-number
0350-intersection-of-two-arrays-ii
0389-find-the-difference
0414-third-maximum-number
1256-rank-transform-of-an-array
2113-find-the-kth-largest-integer-in-the-array
2148-minimum-number-of-moves-to-seat-everyone
2917-count-pairs-whose-sum-is-less-than-target

Sliding Window

0187-repeated-dna-sequences
0219-contains-duplicate-ii
0567-permutation-in-string
0718-maximum-length-of-repeated-subarray
1755-defuse-the-bomb
1987-substrings-of-size-three-with-distinct-characters
2463-minimum-recolors-to-get-k-consecutive-black-blocks

Two Pointers

0011-container-with-most-water
0026-remove-duplicates-from-sorted-array
0027-remove-element
0042-trapping-rain-water
0075-sort-colors
0151-reverse-words-in-a-string
0344-reverse-string
0350-intersection-of-two-arrays-ii
0567-permutation-in-string
0696-count-binary-substrings
0874-backspace-string-compare
1894-merge-strings-alternately
2095-minimum-number-of-swaps-to-make-the-string-balanced
2707-merge-two-2d-arrays-by-summing-values
2917-count-pairs-whose-sum-is-less-than-target

Math

0048-rotate-image
0066-plus-one
0204-count-primes
0258-add-digits
0268-missing-number
0273-integer-to-english-words
0371-sum-of-two-integers
0398-random-pick-index
0405-convert-a-number-to-hexadecimal
0415-add-strings
0486-predict-the-winner
1585-the-kth-factor-of-n
1631-number-of-sub-arrays-with-odd-sum
1889-check-if-number-is-a-sum-of-powers-of-three
2610-closest-prime-numbers-in-range
3568-find-the-key-of-the-numbers

Matrix

0048-rotate-image
0054-spiral-matrix
0059-spiral-matrix-ii
0073-set-matrix-zeroes
0074-search-a-2d-matrix
0498-diagonal-traverse
0566-reshape-the-matrix

Linked List

0024-swap-nodes-in-pairs
1484-linked-list-in-binary-tree

Tree

0257-binary-tree-paths
1484-linked-list-in-binary-tree

Depth-First Search

0257-binary-tree-paths
0386-lexicographical-numbers
1484-linked-list-in-binary-tree

Breadth-First Search

1484-linked-list-in-binary-tree

Binary Tree

0257-binary-tree-paths
1484-linked-list-in-binary-tree

Prefix Sum

0238-product-of-array-except-self
0303-range-sum-query-immutable
1631-number-of-sub-arrays-with-odd-sum

Bit Manipulation

0090-subsets-ii
0136-single-number
0187-repeated-dna-sequences
0268-missing-number
0371-sum-of-two-integers
0389-find-the-difference
0397-integer-replacement
0405-convert-a-number-to-hexadecimal
1786-count-the-number-of-consistent-strings
2323-minimum-bit-flips-to-convert-number
2503-longest-subarray-with-maximum-bitwise-and

Dynamic Programming

0042-trapping-rain-water
0045-jump-game-ii
0053-maximum-subarray
0055-jump-game
0121-best-time-to-buy-and-sell-stock
0397-integer-replacement
0486-predict-the-winner
0718-maximum-length-of-repeated-subarray
1631-number-of-sub-arrays-with-odd-sum
1849-maximum-absolute-sum-of-any-subarray

Recursion

0024-swap-nodes-in-pairs
0273-integer-to-english-words
0486-predict-the-winner

Game Theory

0486-predict-the-winner

Binary Search

0035-search-insert-position
0074-search-a-2d-matrix
0268-missing-number
0278-first-bad-version
0350-intersection-of-two-arrays-ii
0374-guess-number-higher-or-lower
0718-maximum-length-of-repeated-subarray
0792-binary-search
2917-count-pairs-whose-sum-is-less-than-target

Interactive

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

Greedy

0011-container-with-most-water
0045-jump-game-ii
0055-jump-game
0135-candy
0397-integer-replacement
0409-longest-palindrome
0957-minimum-add-to-make-parentheses-valid
2095-minimum-number-of-swaps-to-make-the-string-balanced
2148-minimum-number-of-moves-to-seat-everyone

Stack

0042-trapping-rain-water
0225-implement-stack-using-queues
0735-asteroid-collision
0739-daily-temperatures
0874-backspace-string-compare
0957-minimum-add-to-make-parentheses-valid
1078-remove-outermost-parentheses
2021-remove-all-occurrences-of-a-substring
2095-minimum-number-of-swaps-to-make-the-string-balanced
2800-minimum-string-length-after-removing-substrings

Monotonic Stack

0042-trapping-rain-water
0739-daily-temperatures

String

0058-length-of-last-word
0151-reverse-words-in-a-string
0187-repeated-dna-sequences
0205-isomorphic-strings
0257-binary-tree-paths
0273-integer-to-english-words
0344-reverse-string
0387-first-unique-character-in-a-string
0389-find-the-difference
0409-longest-palindrome
0415-add-strings
0567-permutation-in-string
0696-count-binary-substrings
0874-backspace-string-compare
0920-uncommon-words-from-two-sentences
0957-minimum-add-to-make-parentheses-valid
1078-remove-outermost-parentheses
1205-defanging-an-ip-address
1786-count-the-number-of-consistent-strings
1894-merge-strings-alternately
1987-substrings-of-size-three-with-distinct-characters
2021-remove-all-occurrences-of-a-substring
2095-minimum-number-of-swaps-to-make-the-string-balanced
2113-find-the-kth-largest-integer-in-the-array
2463-minimum-recolors-to-get-k-consecutive-black-blocks
2800-minimum-string-length-after-removing-substrings

Counting

0229-majority-element-ii
0387-first-unique-character-in-a-string
0920-uncommon-words-from-two-sentences
1786-count-the-number-of-consistent-strings
1987-substrings-of-size-three-with-distinct-characters
2486-most-frequent-even-element

Brainteaser

2503-longest-subarray-with-maximum-bitwise-and

Divide and Conquer

0053-maximum-subarray
2113-find-the-kth-largest-integer-in-the-array

Database

0176-second-highest-salary

Simulation

0054-spiral-matrix
0059-spiral-matrix-ii
0258-add-digits
0415-add-strings
0498-diagonal-traverse
0566-reshape-the-matrix
0735-asteroid-collision
0874-backspace-string-compare
1310-watering-plants
2021-remove-all-occurrences-of-a-substring
2800-minimum-string-length-after-removing-substrings

Memoization

0397-integer-replacement

Trie

0386-lexicographical-numbers

Number Theory

0204-count-primes
0258-add-digits
1585-the-kth-factor-of-n
2610-closest-prime-numbers-in-range

Reservoir Sampling

0398-random-pick-index

Randomized

0398-random-pick-index

Enumeration

0204-count-primes

Design

0225-implement-stack-using-queues
0303-range-sum-query-immutable

Rolling Hash

0187-repeated-dna-sequences
0718-maximum-length-of-repeated-subarray

Hash Function

0187-repeated-dna-sequences
0718-maximum-length-of-repeated-subarray

Counting Sort

2148-minimum-number-of-moves-to-seat-everyone

Heap (Priority Queue)

1127-last-stone-weight
2113-find-the-kth-largest-integer-in-the-array

Quickselect

2113-find-the-kth-largest-integer-in-the-array

Backtracking

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

Queue

0225-implement-stack-using-queues
0387-first-unique-character-in-a-string