LeetCode Solutions Repository

Welcome to my LeetCode solutions repository! 🚀
This repository is automatically updated with my solved LeetCode problems, organized in the following structure:

• (problem_number, problem_name).cpp: Contains my solution to the problem with comments on time and space complexity.
• README.md: Includes the full problem statement from LeetCode.
• notes.md: An empty file for future notes or additional thoughts (created automatically).

How It Works

This repository is maintained using LeetHub, a simple Chrome extension that automates the process of pushing solved LeetCode problems to GitHub. It automatically creates the files mentioned above and comments my code with time and space complexity.

🛠️ Check out the LeetHub extension here

Thank You

A big shoutout to the developer of LeetHub for building such an awesome tool! It makes tracking and sharing my progress seamless. 🙌

LeetCode Topics

Two Pointers

0005-longest-palindromic-substring
0015-3sum
0031-next-permutation
0075-sort-colors
2265-partition-array-according-to-given-pivot
2414-move-pieces-to-obtain-a-string
2551-apply-operations-to-an-array
2707-merge-two-2d-arrays-by-summing-values
3018-make-string-a-subsequence-using-cyclic-increments

String

0005-longest-palindromic-substring
0952-word-subsets
1093-recover-a-tree-from-preorder-traversal
1170-shortest-common-supersequence
1460-number-of-substrings-containing-all-three-characters
1502-construct-k-palindrome-strings
1516-the-k-th-lexicographical-string-of-all-happy-strings-of-length-n
1524-string-matching-in-an-array
1537-maximum-score-after-splitting-a-string
1744-number-of-ways-to-form-a-target-string-given-a-dictionary
1895-minimum-number-of-operations-to-move-all-balls-to-each-box
1915-check-if-one-string-swap-can-make-strings-equal
2021-remove-all-occurrences-of-a-substring
2059-unique-length-3-palindromic-subsequences
2107-find-unique-binary-string
2221-check-if-a-parentheses-string-can-be-valid
2292-counting-words-with-a-given-prefix
2300-construct-string-with-repeat-limit
2414-move-pieces-to-obtain-a-string
2456-construct-smallest-number-from-di-string
2463-minimum-recolors-to-get-k-consecutive-black-blocks
2465-shifting-letters-ii
2691-count-vowel-strings-in-ranges
3018-make-string-a-subsequence-using-cyclic-increments
3267-find-longest-special-substring-that-occurs-thrice-i
3309-count-prefix-and-suffix-pairs-i
3447-clear-digits
3455-minimum-length-of-string-after-operations
3569-count-of-substrings-containing-every-vowel-and-k-consonants-ii

Dynamic Programming

0005-longest-palindromic-substring
0494-target-sum
0689-maximum-sum-of-3-non-overlapping-subarrays
0905-length-of-longest-fibonacci-subsequence
1025-minimum-cost-for-tickets
1063-best-sightseeing-pair
1170-shortest-common-supersequence
1631-number-of-sub-arrays-with-odd-sum
1744-number-of-ways-to-form-a-target-string-given-a-dictionary
1849-maximum-absolute-sum-of-any-subarray
2164-two-best-non-overlapping-events
2262-solving-questions-with-brainpower
2562-count-ways-to-build-good-strings

Array

0001-two-sum
0015-3sum
0031-next-permutation
0075-sort-colors
0407-trapping-rain-water-ii
0494-target-sum
0689-maximum-sum-of-3-non-overlapping-subarrays
0780-max-chunks-to-make-sorted
0854-making-a-large-island
0905-length-of-longest-fibonacci-subsequence
0925-construct-binary-tree-from-preorder-and-postorder-traversal
0952-word-subsets
1025-minimum-cost-for-tickets
1063-best-sightseeing-pair
1364-tuple-with-same-product
1396-count-servers-that-communicate
1485-minimum-cost-to-make-at-least-one-valid-path-in-a-grid
1524-string-matching-in-an-array
1570-final-prices-with-a-special-discount-in-a-shop
1631-number-of-sub-arrays-with-odd-sum
1744-number-of-ways-to-form-a-target-string-given-a-dictionary
1819-construct-the-lexicographically-largest-valid-sequence
1849-maximum-absolute-sum-of-any-subarray
1876-map-of-highest-peak
1878-check-if-array-is-sorted-and-rotated
1886-minimum-limit-of-balls-in-a-bag
1895-minimum-number-of-operations-to-move-all-balls-to-each-box
1927-maximum-ascending-subarray-sum
2058-concatenation-of-array
2107-find-unique-binary-string
2145-grid-game
2164-two-best-non-overlapping-events
2262-solving-questions-with-brainpower
2265-partition-array-according-to-given-pivot
2292-counting-words-with-a-given-prefix
2358-number-of-ways-to-split-array
2448-count-number-of-bad-pairs
2465-shifting-letters-ii
2473-max-sum-of-a-pair-with-equal-sum-of-digits
2478-longest-nice-subarray
2533-bitwise-xor-of-all-pairings
2551-apply-operations-to-an-array
2564-most-profitable-path-in-a-tree
2614-maximum-count-of-positive-integer-and-negative-integer
2640-maximum-number-of-integers-to-choose-from-a-range-i
2685-first-completely-painted-row-or-column
2690-house-robber-iv
2691-count-vowel-strings-in-ranges
2692-take-gifts-from-the-richest-pile
2695-find-score-of-an-array-after-marking-all-elements
2707-merge-two-2d-arrays-by-summing-values
2764-maximum-number-of-fish-in-a-grid
2766-find-the-prefix-common-array-of-two-arrays
2891-maximum-beauty-of-an-array-after-applying-operation
3181-find-building-where-alice-and-bob-can-meet
3219-make-lexicographically-smallest-array-by-swapping-elements
3227-find-missing-and-repeated-values
3309-count-prefix-and-suffix-pairs-i
3332-minimum-operations-to-exceed-threshold-value-ii
3372-longest-strictly-increasing-or-strictly-decreasing-subarray
3427-special-array-ii
3429-special-array-i
3434-find-the-number-of-distinct-colors-among-the-balls
3483-alternating-groups-ii
3555-final-array-state-after-k-multiplication-operations-i
3623-count-number-of-trapezoids-i
3643-zero-array-transformation-ii

Hash Table

0001-two-sum
0905-length-of-longest-fibonacci-subsequence
0925-construct-binary-tree-from-preorder-and-postorder-traversal
0952-word-subsets
1364-tuple-with-same-product
1387-find-elements-in-a-contaminated-binary-tree
1460-number-of-substrings-containing-all-three-characters
1502-construct-k-palindrome-strings
1915-check-if-one-string-swap-can-make-strings-equal
2059-unique-length-3-palindromic-subsequences
2107-find-unique-binary-string
2300-construct-string-with-repeat-limit
2434-design-a-number-container-system
2448-count-number-of-bad-pairs
2473-max-sum-of-a-pair-with-equal-sum-of-digits
2640-maximum-number-of-integers-to-choose-from-a-range-i
2685-first-completely-painted-row-or-column
2695-find-score-of-an-array-after-marking-all-elements
2707-merge-two-2d-arrays-by-summing-values
2766-find-the-prefix-common-array-of-two-arrays
3227-find-missing-and-repeated-values
3267-find-longest-special-substring-that-occurs-thrice-i
3434-find-the-number-of-distinct-colors-among-the-balls
3455-minimum-length-of-string-after-operations
3569-count-of-substrings-containing-every-vowel-and-k-consonants-ii
3623-count-number-of-trapezoids-i

Binary Search

1886-minimum-limit-of-balls-in-a-bag
2164-two-best-non-overlapping-events
2614-maximum-count-of-positive-integer-and-negative-integer
2640-maximum-number-of-integers-to-choose-from-a-range-i
2690-house-robber-iv
2891-maximum-beauty-of-an-array-after-applying-operation
3181-find-building-where-alice-and-bob-can-meet
3267-find-longest-special-substring-that-occurs-thrice-i
3427-special-array-ii
3643-zero-array-transformation-ii

Greedy

0780-max-chunks-to-make-sorted
1502-construct-k-palindrome-strings
2221-check-if-a-parentheses-string-can-be-valid
2300-construct-string-with-repeat-limit
2456-construct-smallest-number-from-di-string
2509-minimize-xor
2640-maximum-number-of-integers-to-choose-from-a-range-i

Sorting

0015-3sum
0075-sort-colors
0780-max-chunks-to-make-sorted
2164-two-best-non-overlapping-events
2473-max-sum-of-a-pair-with-equal-sum-of-digits
2640-maximum-number-of-integers-to-choose-from-a-range-i
2695-find-score-of-an-array-after-marking-all-elements
2891-maximum-beauty-of-an-array-after-applying-operation
3219-make-lexicographically-smallest-array-by-swapping-elements

Heap (Priority Queue)

0407-trapping-rain-water-ii
1485-minimum-cost-to-make-at-least-one-valid-path-in-a-grid
2164-two-best-non-overlapping-events
2300-construct-string-with-repeat-limit
2434-design-a-number-container-system
2473-max-sum-of-a-pair-with-equal-sum-of-digits
2692-take-gifts-from-the-richest-pile
2695-find-score-of-an-array-after-marking-all-elements
3181-find-building-where-alice-and-bob-can-meet
3332-minimum-operations-to-exceed-threshold-value-ii
3555-final-array-state-after-k-multiplication-operations-i

Prefix Sum

1537-maximum-score-after-splitting-a-string
1631-number-of-sub-arrays-with-odd-sum
1895-minimum-number-of-operations-to-move-all-balls-to-each-box
2059-unique-length-3-palindromic-subsequences
2145-grid-game
2358-number-of-ways-to-split-array
2465-shifting-letters-ii
2691-count-vowel-strings-in-ranges
3427-special-array-ii
3643-zero-array-transformation-ii

Sliding Window

1460-number-of-substrings-containing-all-three-characters
2463-minimum-recolors-to-get-k-consecutive-black-blocks
2478-longest-nice-subarray
2891-maximum-beauty-of-an-array-after-applying-operation
3267-find-longest-special-substring-that-occurs-thrice-i
3483-alternating-groups-ii
3569-count-of-substrings-containing-every-vowel-and-k-consonants-ii

Counting

1364-tuple-with-same-product
1396-count-servers-that-communicate
1502-construct-k-palindrome-strings
1915-check-if-one-string-swap-can-make-strings-equal
2300-construct-string-with-repeat-limit
2448-count-number-of-bad-pairs
2614-maximum-count-of-positive-integer-and-negative-integer
3267-find-longest-special-substring-that-occurs-thrice-i
3455-minimum-length-of-string-after-operations

Simulation

2021-remove-all-occurrences-of-a-substring
2058-concatenation-of-array
2265-partition-array-according-to-given-pivot
2551-apply-operations-to-an-array
2692-take-gifts-from-the-richest-pile
2695-find-score-of-an-array-after-marking-all-elements
3332-minimum-operations-to-exceed-threshold-value-ii
3434-find-the-number-of-distinct-colors-among-the-balls
3447-clear-digits
3555-final-array-state-after-k-multiplication-operations-i

Math

1631-number-of-sub-arrays-with-odd-sum
1889-check-if-number-is-a-sum-of-powers-of-three
2448-count-number-of-bad-pairs
2649-count-total-number-of-colored-cells
2802-find-the-punishment-number-of-an-integer
3227-find-missing-and-repeated-values
3555-final-array-state-after-k-multiplication-operations-i
3623-count-number-of-trapezoids-i

Stack

0780-max-chunks-to-make-sorted
1570-final-prices-with-a-special-discount-in-a-shop
2021-remove-all-occurrences-of-a-substring
2221-check-if-a-parentheses-string-can-be-valid
2456-construct-smallest-number-from-di-string
3181-find-building-where-alice-and-bob-can-meet
3447-clear-digits

Monotonic Stack

0780-max-chunks-to-make-sorted
1570-final-prices-with-a-special-discount-in-a-shop
3181-find-building-where-alice-and-bob-can-meet

Tree

0515-find-largest-value-in-each-tree-row
0925-construct-binary-tree-from-preorder-and-postorder-traversal
1093-recover-a-tree-from-preorder-traversal
1387-find-elements-in-a-contaminated-binary-tree
2564-most-profitable-path-in-a-tree
3058-maximum-number-of-k-divisible-components
3439-find-minimum-diameter-after-merging-two-trees

Depth-First Search

0515-find-largest-value-in-each-tree-row
0684-redundant-connection
0820-find-eventual-safe-states
0854-making-a-large-island
1093-recover-a-tree-from-preorder-traversal
1387-find-elements-in-a-contaminated-binary-tree
1396-count-servers-that-communicate
1558-course-schedule-iv
2246-maximum-employees-to-be-invited-to-a-meeting
2564-most-profitable-path-in-a-tree
2764-maximum-number-of-fish-in-a-grid
3058-maximum-number-of-k-divisible-components
3439-find-minimum-diameter-after-merging-two-trees

Binary Indexed Tree

3181-find-building-where-alice-and-bob-can-meet

Segment Tree

3181-find-building-where-alice-and-bob-can-meet

Breadth-First Search

0407-trapping-rain-water-ii
0515-find-largest-value-in-each-tree-row
0684-redundant-connection
0820-find-eventual-safe-states
0854-making-a-large-island
1387-find-elements-in-a-contaminated-binary-tree
1396-count-servers-that-communicate
1485-minimum-cost-to-make-at-least-one-valid-path-in-a-grid
1558-course-schedule-iv
1876-map-of-highest-peak
2564-most-profitable-path-in-a-tree
2583-divide-nodes-into-the-maximum-number-of-groups
2764-maximum-number-of-fish-in-a-grid
3439-find-minimum-diameter-after-merging-two-trees

Graph

0684-redundant-connection
0820-find-eventual-safe-states
1485-minimum-cost-to-make-at-least-one-valid-path-in-a-grid
1558-course-schedule-iv
2246-maximum-employees-to-be-invited-to-a-meeting
2564-most-profitable-path-in-a-tree
2583-divide-nodes-into-the-maximum-number-of-groups
3439-find-minimum-diameter-after-merging-two-trees

Binary Tree

0515-find-largest-value-in-each-tree-row
0925-construct-binary-tree-from-preorder-and-postorder-traversal
1093-recover-a-tree-from-preorder-traversal
1387-find-elements-in-a-contaminated-binary-tree

Backtracking

0494-target-sum
1516-the-k-th-lexicographical-string-of-all-happy-strings-of-length-n
1819-construct-the-lexicographically-largest-valid-sequence
2107-find-unique-binary-string
2456-construct-smallest-number-from-di-string
2802-find-the-punishment-number-of-an-integer

Bit Manipulation

2059-unique-length-3-palindromic-subsequences
2478-longest-nice-subarray
2509-minimize-xor
2533-bitwise-xor-of-all-pairings
2766-find-the-prefix-common-array-of-two-arrays

String Matching

1524-string-matching-in-an-array
2292-counting-words-with-a-given-prefix
3309-count-prefix-and-suffix-pairs-i

Trie

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

Rolling Hash

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

Hash Function

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

Brainteaser

2533-bitwise-xor-of-all-pairings

Matrix

0407-trapping-rain-water-ii
0854-making-a-large-island
1396-count-servers-that-communicate
1485-minimum-cost-to-make-at-least-one-valid-path-in-a-grid
1876-map-of-highest-peak
2145-grid-game
2685-first-completely-painted-row-or-column
2764-maximum-number-of-fish-in-a-grid
3227-find-missing-and-repeated-values

Shortest Path

1485-minimum-cost-to-make-at-least-one-valid-path-in-a-grid

Union Find

0684-redundant-connection
0854-making-a-large-island
1396-count-servers-that-communicate
2583-divide-nodes-into-the-maximum-number-of-groups
2764-maximum-number-of-fish-in-a-grid
3219-make-lexicographically-smallest-array-by-swapping-elements

Topological Sort

0820-find-eventual-safe-states
1558-course-schedule-iv
2246-maximum-employees-to-be-invited-to-a-meeting

Design

1387-find-elements-in-a-contaminated-binary-tree
2434-design-a-number-container-system

Ordered Set

2434-design-a-number-container-system

Divide and Conquer

0925-construct-binary-tree-from-preorder-and-postorder-traversal

Geometry

3623-count-number-of-trapezoids-i