Leetcode_Problem_Solving

LeetCode Topics

Math

0009-palindrome-number
0029-divide-two-integers
0062-unique-paths
0066-plus-one
0070-climbing-stairs
0168-excel-sheet-column-title
0171-excel-sheet-column-number
0202-happy-number
0273-integer-to-english-words
0593-valid-square
1013-fibonacci-number
1018-largest-perimeter-triangle
1086-divisor-game
1236-n-th-tribonacci-number
1635-number-of-good-pairs
2630-alternating-digit-sum
2716-prime-subtraction-operation
3227-find-missing-and-repeated-values
3555-final-array-state-after-k-multiplication-operations-i

Dynamic Programming

0022-generate-parentheses
0032-longest-valid-parentheses
0042-trapping-rain-water
0053-maximum-subarray
0055-jump-game
0062-unique-paths
0064-minimum-path-sum
0070-climbing-stairs
0118-pascals-triangle
0119-pascals-triangle-ii
0198-house-robber
0413-arithmetic-slices
1013-fibonacci-number
1086-divisor-game
1236-n-th-tribonacci-number

Memoization

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

Array

0001-two-sum
0026-remove-duplicates-from-sorted-array
0035-search-insert-position
0036-valid-sudoku
0037-sudoku-solver
0039-combination-sum
0041-first-missing-positive
0042-trapping-rain-water
0047-permutations-ii
0049-group-anagrams
0053-maximum-subarray
0055-jump-game
0056-merge-intervals
0064-minimum-path-sum
0066-plus-one
0068-text-justification
0074-search-a-2d-matrix
0078-subsets
0079-word-search
0084-largest-rectangle-in-histogram
0118-pascals-triangle
0119-pascals-triangle-ii
0128-longest-consecutive-sequence
0135-candy
0167-two-sum-ii-input-array-is-sorted
0169-majority-element
0198-house-robber
0215-kth-largest-element-in-an-array
0217-contains-duplicate
0283-move-zeroes
0413-arithmetic-slices
0455-assign-cookies
0463-island-perimeter
0485-max-consecutive-ones
0575-distribute-candies
0735-asteroid-collision
0787-sliding-puzzle
0861-flipping-an-image
0892-shortest-subarray-with-sum-at-least-k
0907-koko-eating-bananas
1018-largest-perimeter-triangle
1019-squares-of-a-sorted-array
1147-flip-columns-for-maximum-number-of-equal-rows
1468-check-if-n-and-its-double-exist
1570-final-prices-with-a-special-discount-in-a-shop
1635-number-of-good-pairs
1679-shortest-subarray-to-be-removed-to-make-array-sorted
1755-defuse-the-bomb
1833-find-the-highest-altitude
1923-sentence-similarity-iii
1940-maximum-xor-for-each-query
1972-rotating-the-box
2048-build-array-from-permutation
2089-maximum-matrix-sum
2093-check-if-string-is-a-prefix-of-array
2179-most-beautiful-item-for-each-query
2188-minimized-maximum-of-products-distributed-to-any-store
2232-adding-spaces-to-a-string
2245-destroying-asteroids
2292-counting-words-with-a-given-prefix
2308-divide-array-into-equal-pairs
2343-count-unguarded-cells-in-the-grid
2375-minimum-obstacle-removal-to-reach-corner
2442-number-of-arithmetic-triplets
2551-apply-operations-to-an-array
2552-maximum-sum-of-distinct-subarrays-with-length-k
2614-maximum-count-of-positive-integer-and-negative-integer
2640-maximum-number-of-integers-to-choose-from-a-range-i
2692-take-gifts-from-the-richest-pile
2698-find-the-array-concatenation-value
2699-count-the-number-of-fair-pairs
2711-minimum-time-to-visit-a-cell-in-a-grid
2716-prime-subtraction-operation
2876-number-of-employees-who-met-the-target
2977-check-if-a-string-is-an-acronym-of-words
3165-find-indices-with-index-and-value-difference-i
3227-find-missing-and-repeated-values
3309-count-prefix-and-suffix-pairs-i
3324-split-the-array
3380-shortest-subarray-with-or-at-least-k-ii
3471-minimum-average-of-smallest-and-largest-elements
3517-shortest-distance-after-road-addition-queries-i
3522-find-the-power-of-k-size-subarrays-i
3555-final-array-state-after-k-multiplication-operations-i

Hash Table

0001-two-sum
0017-letter-combinations-of-a-phone-number
0036-valid-sudoku
0037-sudoku-solver
0041-first-missing-positive
0049-group-anagrams
0127-word-ladder
0128-longest-consecutive-sequence
0169-majority-element
0202-happy-number
0217-contains-duplicate
0242-valid-anagram
0383-ransom-note
0387-first-unique-character-in-a-string
0389-find-the-difference
0575-distribute-candies
1147-flip-columns-for-maximum-number-of-equal-rows
1297-maximum-number-of-balloons
1468-check-if-n-and-its-double-exist
1635-number-of-good-pairs
2308-divide-array-into-equal-pairs
2427-first-letter-to-appear-twice
2442-number-of-arithmetic-triplets
2552-maximum-sum-of-distinct-subarrays-with-length-k
2599-take-k-of-each-character-from-left-and-right
2640-maximum-number-of-integers-to-choose-from-a-range-i
3227-find-missing-and-repeated-values
3324-split-the-array
3455-minimum-length-of-string-after-operations
3753-maximum-difference-between-even-and-odd-frequency-i

Bit Manipulation

0029-divide-two-integers
0078-subsets
0222-count-complete-tree-nodes
0389-find-the-difference
0861-flipping-an-image
1441-minimum-flips-to-make-a-or-b-equal-to-c
1940-maximum-xor-for-each-query
2308-divide-array-into-equal-pairs
2427-first-letter-to-appear-twice
3380-shortest-subarray-with-or-at-least-k-ii
3394-minimum-array-end

Prefix Sum

0892-shortest-subarray-with-sum-at-least-k
1833-find-the-highest-altitude
1940-maximum-xor-for-each-query

Divide and Conquer

0053-maximum-subarray
0169-majority-element
0215-kth-largest-element-in-an-array

Sorting

0049-group-anagrams
0056-merge-intervals
0169-majority-element
0215-kth-largest-element-in-an-array
0217-contains-duplicate
0242-valid-anagram
0389-find-the-difference
0455-assign-cookies
1018-largest-perimeter-triangle
1019-squares-of-a-sorted-array
1468-check-if-n-and-its-double-exist
2179-most-beautiful-item-for-each-query
2245-destroying-asteroids
2640-maximum-number-of-integers-to-choose-from-a-range-i
2699-count-the-number-of-fair-pairs
3471-minimum-average-of-smallest-and-largest-elements

Heap (Priority Queue)

0215-kth-largest-element-in-an-array
0892-shortest-subarray-with-sum-at-least-k
2375-minimum-obstacle-removal-to-reach-corner
2692-take-gifts-from-the-richest-pile
2711-minimum-time-to-visit-a-cell-in-a-grid
3555-final-array-state-after-k-multiplication-operations-i

Quickselect

0215-kth-largest-element-in-an-array

Backtracking

0017-letter-combinations-of-a-phone-number
0022-generate-parentheses
0037-sudoku-solver
0039-combination-sum
0047-permutations-ii
0078-subsets
0079-word-search

Binary Search

0035-search-insert-position
0074-search-a-2d-matrix
0167-two-sum-ii-input-array-is-sorted
0222-count-complete-tree-nodes
0892-shortest-subarray-with-sum-at-least-k
0907-koko-eating-bananas
1468-check-if-n-and-its-double-exist
1679-shortest-subarray-to-be-removed-to-make-array-sorted
2179-most-beautiful-item-for-each-query
2188-minimized-maximum-of-products-distributed-to-any-store
2614-maximum-count-of-positive-integer-and-negative-integer
2640-maximum-number-of-integers-to-choose-from-a-range-i
2699-count-the-number-of-fair-pairs
2716-prime-subtraction-operation

Greedy

0055-jump-game
0135-candy
0455-assign-cookies
1018-largest-perimeter-triangle
2089-maximum-matrix-sum
2221-check-if-a-parentheses-string-can-be-valid
2245-destroying-asteroids
2640-maximum-number-of-integers-to-choose-from-a-range-i
2716-prime-subtraction-operation

Number Theory

2716-prime-subtraction-operation

Geometry

0593-valid-square

Two Pointers

0026-remove-duplicates-from-sorted-array
0042-trapping-rain-water
0167-two-sum-ii-input-array-is-sorted
0202-happy-number
0283-move-zeroes
0344-reverse-string
0455-assign-cookies
0541-reverse-string-ii
0557-reverse-words-in-a-string-iii
0861-flipping-an-image
0874-backspace-string-compare
0908-middle-of-the-linked-list
0953-reverse-only-letters
1019-squares-of-a-sorted-array
1468-check-if-n-and-its-double-exist
1566-check-if-a-word-occurs-as-a-prefix-of-any-word-in-a-sentence
1679-shortest-subarray-to-be-removed-to-make-array-sorted
1923-sentence-similarity-iii
1972-rotating-the-box
2093-check-if-string-is-a-prefix-of-array
2216-delete-the-middle-node-of-a-linked-list
2232-adding-spaces-to-a-string
2442-number-of-arithmetic-triplets
2551-apply-operations-to-an-array
2698-find-the-array-concatenation-value
2699-count-the-number-of-fair-pairs
3018-make-string-a-subsequence-using-cyclic-increments
3165-find-indices-with-index-and-value-difference-i
3471-minimum-average-of-smallest-and-largest-elements

Union Find

0128-longest-consecutive-sequence

String

0017-letter-combinations-of-a-phone-number
0020-valid-parentheses
0022-generate-parentheses
0032-longest-valid-parentheses
0049-group-anagrams
0068-text-justification
0079-word-search
0127-word-ladder
0168-excel-sheet-column-title
0171-excel-sheet-column-number
0242-valid-anagram
0273-integer-to-english-words
0344-reverse-string
0383-ransom-note
0387-first-unique-character-in-a-string
0389-find-the-difference
0541-reverse-string-ii
0557-reverse-words-in-a-string-iii
0874-backspace-string-compare
0886-score-of-parentheses
0953-reverse-only-letters
1297-maximum-number-of-balloons
1566-check-if-a-word-occurs-as-a-prefix-of-any-word-in-a-sentence
1923-sentence-similarity-iii
2093-check-if-string-is-a-prefix-of-array
2221-check-if-a-parentheses-string-can-be-valid
2232-adding-spaces-to-a-string
2292-counting-words-with-a-given-prefix
2427-first-letter-to-appear-twice
2463-minimum-recolors-to-get-k-consecutive-black-blocks
2599-take-k-of-each-character-from-left-and-right
2977-check-if-a-string-is-an-acronym-of-words
3018-make-string-a-subsequence-using-cyclic-increments
3309-count-prefix-and-suffix-pairs-i
3455-minimum-length-of-string-after-operations
3753-maximum-difference-between-even-and-odd-frequency-i

Counting

0169-majority-element
0383-ransom-note
0387-first-unique-character-in-a-string
1297-maximum-number-of-balloons
1635-number-of-good-pairs
2308-divide-array-into-equal-pairs
2427-first-letter-to-appear-twice
2614-maximum-count-of-positive-integer-and-negative-integer
3324-split-the-array
3455-minimum-length-of-string-after-operations
3753-maximum-difference-between-even-and-odd-frequency-i

Stack

0020-valid-parentheses
0032-longest-valid-parentheses
0042-trapping-rain-water
0084-largest-rectangle-in-histogram
0094-binary-tree-inorder-traversal
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0232-implement-queue-using-stacks
0735-asteroid-collision
0874-backspace-string-compare
0886-score-of-parentheses
1570-final-prices-with-a-special-discount-in-a-shop
1679-shortest-subarray-to-be-removed-to-make-array-sorted
2221-check-if-a-parentheses-string-can-be-valid

Monotonic Stack

0042-trapping-rain-water
0084-largest-rectangle-in-histogram
1570-final-prices-with-a-special-discount-in-a-shop
1679-shortest-subarray-to-be-removed-to-make-array-sorted

Sliding Window

0413-arithmetic-slices
0892-shortest-subarray-with-sum-at-least-k
1755-defuse-the-bomb
2463-minimum-recolors-to-get-k-consecutive-black-blocks
2552-maximum-sum-of-distinct-subarrays-with-length-k
2599-take-k-of-each-character-from-left-and-right
3380-shortest-subarray-with-or-at-least-k-ii
3522-find-the-power-of-k-size-subarrays-i

Queue

0232-implement-queue-using-stacks
0387-first-unique-character-in-a-string
0892-shortest-subarray-with-sum-at-least-k

Monotonic Queue

0892-shortest-subarray-with-sum-at-least-k

Matrix

0036-valid-sudoku
0037-sudoku-solver
0064-minimum-path-sum
0074-search-a-2d-matrix
0079-word-search
0463-island-perimeter
0787-sliding-puzzle
0861-flipping-an-image
1147-flip-columns-for-maximum-number-of-equal-rows
1972-rotating-the-box
2089-maximum-matrix-sum
2343-count-unguarded-cells-in-the-grid
2375-minimum-obstacle-removal-to-reach-corner
2711-minimum-time-to-visit-a-cell-in-a-grid
3227-find-missing-and-repeated-values

Simulation

0068-text-justification
0735-asteroid-collision
0861-flipping-an-image
0874-backspace-string-compare
2048-build-array-from-permutation
2232-adding-spaces-to-a-string
2343-count-unguarded-cells-in-the-grid
2551-apply-operations-to-an-array
2692-take-gifts-from-the-richest-pile
2698-find-the-array-concatenation-value
3555-final-array-state-after-k-multiplication-operations-i

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
0111-minimum-depth-of-binary-tree
0127-word-ladder
0226-invert-binary-tree
0463-island-perimeter
0787-sliding-puzzle
2375-minimum-obstacle-removal-to-reach-corner
2711-minimum-time-to-visit-a-cell-in-a-grid
3517-shortest-distance-after-road-addition-queries-i

Graph

2201-valid-arrangement-of-pairs
2375-minimum-obstacle-removal-to-reach-corner
2711-minimum-time-to-visit-a-cell-in-a-grid
3517-shortest-distance-after-road-addition-queries-i

Shortest Path

2375-minimum-obstacle-removal-to-reach-corner
2711-minimum-time-to-visit-a-cell-in-a-grid

Enumeration

2442-number-of-arithmetic-triplets

Depth-First Search

0079-word-search
0094-binary-tree-inorder-traversal
0100-same-tree
0101-symmetric-tree
0104-maximum-depth-of-binary-tree
0111-minimum-depth-of-binary-tree
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0226-invert-binary-tree
0463-island-perimeter
0572-subtree-of-another-tree
0904-leaf-similar-trees
2201-valid-arrangement-of-pairs

Eulerian Circuit

2201-valid-arrangement-of-pairs

String Matching

0572-subtree-of-another-tree
1566-check-if-a-word-occurs-as-a-prefix-of-any-word-in-a-sentence
2292-counting-words-with-a-given-prefix
3309-count-prefix-and-suffix-pairs-i

Recursion

0021-merge-two-sorted-lists
0206-reverse-linked-list
0273-integer-to-english-words
1013-fibonacci-number

Brainteaser

1086-divisor-game

Game Theory

1086-divisor-game

Design

0232-implement-queue-using-stacks

Tree

0094-binary-tree-inorder-traversal
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
0111-minimum-depth-of-binary-tree
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0222-count-complete-tree-nodes
0226-invert-binary-tree
0572-subtree-of-another-tree
0904-leaf-similar-trees

Binary Tree

0094-binary-tree-inorder-traversal
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
0111-minimum-depth-of-binary-tree
0144-binary-tree-preorder-traversal
0145-binary-tree-postorder-traversal
0222-count-complete-tree-nodes
0226-invert-binary-tree
0572-subtree-of-another-tree
0904-leaf-similar-trees

Hash Function

0572-subtree-of-another-tree
3309-count-prefix-and-suffix-pairs-i

Trie

3309-count-prefix-and-suffix-pairs-i

Rolling Hash

3309-count-prefix-and-suffix-pairs-i

Linked List

0021-merge-two-sorted-lists
0206-reverse-linked-list
0908-middle-of-the-linked-list
2216-delete-the-middle-node-of-a-linked-list

Database

0197-rising-temperature
0577-employee-bonus
0610-triangle-judgement
0619-biggest-single-number
0620-not-boring-movies
1153-product-sales-analysis-i
1877-find-followers-count

Combinatorics

0062-unique-paths