leetcode-solutions

All my solved LeetCode problems

LeetCode Topics

Math

0007-reverse-integer
0009-palindrome-number
0013-roman-to-integer
0062-unique-paths
0066-plus-one
0067-add-binary
0069-sqrtx
0070-climbing-stairs
0189-rotate-array
0202-happy-number
0231-power-of-two
0268-missing-number
0292-nim-game
0326-power-of-three
0342-power-of-four
0412-fizz-buzz
0504-base-7
0507-perfect-number
0564-find-the-closest-palindrome
0628-maximum-product-of-three-numbers
0728-self-dividing-numbers
0767-prime-number-of-set-bits-in-binary-representation
0830-largest-triangle-area
0909-stone-game
0950-x-of-a-kind-in-a-deck-of-cards
0989-add-to-array-form-of-integer
1013-fibonacci-number
1086-divisor-game
1236-n-th-tribonacci-number
1260-day-of-the-year
1289-day-of-the-week
1362-airplane-seat-assignment-probability
1406-subtract-the-product-and-sum-of-digits-of-an-integer
1421-find-numbers-with-even-number-of-digits
1817-calculate-money-in-leetcode-bank
1920-determine-color-of-a-chessboard-square
1950-sign-of-the-product-of-an-array
1965-sum-of-digits-in-base-k
2032-largest-odd-number-in-string
2238-a-number-after-a-double-reversal
2481-strictly-palindromic-number
2571-find-the-pivot-integer
2624-difference-between-element-sum-and-digit-sum-of-an-array
2630-alternating-digit-sum
2704-maximum-difference-by-remapping-a-digit
3172-divisible-and-non-divisible-sums-difference
3199-distribute-candies-among-children-i
3201-distribute-candies-among-children-ii
3321-type-of-triangle
3783-mirror-distance-of-an-integer

Bit Manipulation

0067-add-binary
0136-single-number
0191-number-of-1-bits
0231-power-of-two
0268-missing-number
0342-power-of-four
0389-find-the-difference
0476-number-complement
0767-prime-number-of-set-bits-in-binary-representation
2323-minimum-bit-flips-to-convert-number

Array

0001-two-sum
0004-median-of-two-sorted-arrays
0011-container-with-most-water
0015-3sum
0026-remove-duplicates-from-sorted-array
0027-remove-element
0035-search-insert-position
0036-valid-sudoku
0053-maximum-subarray
0066-plus-one
0075-sort-colors
0088-merge-sorted-array
0118-pascals-triangle
0121-best-time-to-buy-and-sell-stock
0122-best-time-to-buy-and-sell-stock-ii
0135-candy
0136-single-number
0169-majority-element
0189-rotate-array
0268-missing-number
0347-top-k-frequent-elements
0349-intersection-of-two-arrays
0350-intersection-of-two-arrays-ii
0414-third-maximum-number
0463-island-perimeter
0540-single-element-in-a-sorted-array
0566-reshape-the-matrix
0594-longest-harmonious-subsequence
0628-maximum-product-of-three-numbers
0733-flood-fill
0777-toeplitz-matrix
0830-largest-triangle-area
0909-stone-game
0948-sort-an-array
0950-x-of-a-kind-in-a-deck-of-cards
0989-add-to-array-form-of-integer
1019-squares-of-a-sorted-array
1221-element-appearing-more-than-25-in-sorted-array
1293-three-consecutive-odds
1388-greatest-sum-divisible-by-three
1392-find-the-difference-of-two-arrays
1421-find-numbers-with-even-number-of-digits
1950-sign-of-the-product-of-an-array
2048-build-array-from-permutation
2058-concatenation-of-array
2144-maximum-difference-between-increasing-elements
2204-find-subsequence-of-length-k-with-the-largest-sum
2215-finding-3-digit-even-numbers
2219-maximum-number-of-words-found-in-sentences
2320-find-all-k-distant-indices-in-an-array
2387-partition-array-such-that-maximum-difference-is-k
2624-difference-between-element-sum-and-digit-sum-of-an-array
2639-separate-the-digits-in-an-array
2654-count-the-number-of-vowel-strings-in-range
2847-find-maximum-number-of-string-pairs
2977-check-if-a-string-is-an-acronym-of-words
3143-longest-unequal-adjacent-groups-subsequence-i
3171-minimum-equal-sum-of-two-arrays-after-replacing-zeros
3194-find-words-containing-character
3206-find-common-elements-between-two-arrays
3241-divide-array-into-arrays-with-max-difference
3321-type-of-triangle
3397-find-the-integer-added-to-array-i
3471-minimum-average-of-smallest-and-largest-elements
3685-count-subarrays-of-length-three-with-a-condition
3747-maximum-difference-between-adjacent-elements-in-a-circular-array

Dynamic Programming

0053-maximum-subarray
0062-unique-paths
0070-climbing-stairs
0118-pascals-triangle
0121-best-time-to-buy-and-sell-stock
0122-best-time-to-buy-and-sell-stock-ii
0392-is-subsequence
0909-stone-game
1013-fibonacci-number
1086-divisor-game
1236-n-th-tribonacci-number
1362-airplane-seat-assignment-probability
1388-greatest-sum-divisible-by-three
3143-longest-unequal-adjacent-groups-subsequence-i

Greedy

0011-container-with-most-water
0122-best-time-to-buy-and-sell-stock-ii
0135-candy
1388-greatest-sum-divisible-by-three
2032-largest-odd-number-in-string
2387-partition-array-such-that-maximum-difference-is-k
2704-maximum-difference-by-remapping-a-digit
3143-longest-unequal-adjacent-groups-subsequence-i
3171-minimum-equal-sum-of-two-arrays-after-replacing-zeros
3241-divide-array-into-arrays-with-max-difference
3360-minimum-deletions-to-make-string-k-special

Sorting

0015-3sum
0075-sort-colors
0088-merge-sorted-array
0169-majority-element
0268-missing-number
0347-top-k-frequent-elements
0349-intersection-of-two-arrays
0350-intersection-of-two-arrays-ii
0389-find-the-difference
0414-third-maximum-number
0594-longest-harmonious-subsequence
0628-maximum-product-of-three-numbers
0948-sort-an-array
1019-squares-of-a-sorted-array
1388-greatest-sum-divisible-by-three
2204-find-subsequence-of-length-k-with-the-largest-sum
2215-finding-3-digit-even-numbers
2387-partition-array-such-that-maximum-difference-is-k
3241-divide-array-into-arrays-with-max-difference
3321-type-of-triangle
3360-minimum-deletions-to-make-string-k-special
3471-minimum-average-of-smallest-and-largest-elements

Brainteaser

0292-nim-game
1086-divisor-game
1362-airplane-seat-assignment-probability
2481-strictly-palindromic-number

Game Theory

0292-nim-game
0909-stone-game
1086-divisor-game

Two Pointers

0011-container-with-most-water
0015-3sum
0026-remove-duplicates-from-sorted-array
0027-remove-element
0028-find-the-index-of-the-first-occurrence-in-a-string
0075-sort-colors
0088-merge-sorted-array
0189-rotate-array
0202-happy-number
0345-reverse-vowels-of-a-string
0349-intersection-of-two-arrays
0350-intersection-of-two-arrays-ii
0392-is-subsequence
1019-squares-of-a-sorted-array
2320-find-all-k-distant-indices-in-an-array
2481-strictly-palindromic-number
3471-minimum-average-of-smallest-and-largest-elements

Hash Table

0001-two-sum
0013-roman-to-integer
0036-valid-sudoku
0169-majority-element
0202-happy-number
0268-missing-number
0347-top-k-frequent-elements
0349-intersection-of-two-arrays
0350-intersection-of-two-arrays-ii
0389-find-the-difference
0594-longest-harmonious-subsequence
0782-jewels-and-stones
0950-x-of-a-kind-in-a-deck-of-cards
1392-find-the-difference-of-two-arrays
2204-find-subsequence-of-length-k-with-the-largest-sum
2215-finding-3-digit-even-numbers
2847-find-maximum-number-of-string-pairs
3206-find-common-elements-between-two-arrays
3360-minimum-deletions-to-make-string-k-special
3753-maximum-difference-between-even-and-odd-frequency-i

String

0013-roman-to-integer
0028-find-the-index-of-the-first-occurrence-in-a-string
0058-length-of-last-word
0067-add-binary
0345-reverse-vowels-of-a-string
0389-find-the-difference
0392-is-subsequence
0412-fizz-buzz
0564-find-the-closest-palindrome
0742-to-lower-case
0782-jewels-and-stones
0812-rotate-string
1205-defanging-an-ip-address
1260-day-of-the-year
1920-determine-color-of-a-chessboard-square
2032-largest-odd-number-in-string
2219-maximum-number-of-words-found-in-sentences
2260-divide-a-string-into-groups-of-size-k
2654-count-the-number-of-vowel-strings-in-range
2847-find-maximum-number-of-string-pairs
2886-faulty-keyboard
2977-check-if-a-string-is-an-acronym-of-words
3143-longest-unequal-adjacent-groups-subsequence-i
3194-find-words-containing-character
3360-minimum-deletions-to-make-string-k-special
3753-maximum-difference-between-even-and-odd-frequency-i

Simulation

0067-add-binary
0412-fizz-buzz
0566-reshape-the-matrix
2048-build-array-from-permutation
2058-concatenation-of-array
2260-divide-a-string-into-groups-of-size-k
2639-separate-the-digits-in-an-array
2847-find-maximum-number-of-string-pairs
2886-faulty-keyboard

Counting

0169-majority-element
0347-top-k-frequent-elements
0594-longest-harmonious-subsequence
0950-x-of-a-kind-in-a-deck-of-cards
2654-count-the-number-of-vowel-strings-in-range
3360-minimum-deletions-to-make-string-k-special
3753-maximum-difference-between-even-and-odd-frequency-i

Prefix Sum

2571-find-the-pivot-integer

Enumeration

2215-finding-3-digit-even-numbers
3199-distribute-candies-among-children-i
3201-distribute-candies-among-children-ii

Probability and Statistics

1362-airplane-seat-assignment-probability

Number Theory

0950-x-of-a-kind-in-a-deck-of-cards

Matrix

0036-valid-sudoku
0463-island-perimeter
0566-reshape-the-matrix
0733-flood-fill
0777-toeplitz-matrix

Depth-First Search

0463-island-perimeter
0733-flood-fill

Breadth-First Search

0463-island-perimeter
0733-flood-fill

Binary Search

0004-median-of-two-sorted-arrays
0035-search-insert-position
0069-sqrtx
0268-missing-number
0349-intersection-of-two-arrays
0350-intersection-of-two-arrays-ii
0540-single-element-in-a-sorted-array

Recursion

0021-merge-two-sorted-lists
0231-power-of-two
0326-power-of-three
0342-power-of-four
1013-fibonacci-number

Memoization

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

Divide and Conquer

0004-median-of-two-sorted-arrays
0053-maximum-subarray
0169-majority-element
0191-number-of-1-bits
0347-top-k-frequent-elements
0948-sort-an-array

Linked List

0021-merge-two-sorted-lists
0083-remove-duplicates-from-sorted-list

String Matching

0028-find-the-index-of-the-first-occurrence-in-a-string
0812-rotate-string

Combinatorics

0062-unique-paths
3199-distribute-candies-among-children-i
3201-distribute-candies-among-children-ii

Heap (Priority Queue)

0347-top-k-frequent-elements
0948-sort-an-array
2204-find-subsequence-of-length-k-with-the-largest-sum

Merge Sort

0948-sort-an-array

Bucket Sort

0347-top-k-frequent-elements
0948-sort-an-array

Radix Sort

0948-sort-an-array

Counting Sort

0948-sort-an-array

Geometry

0830-largest-triangle-area

Sliding Window

0594-longest-harmonious-subsequence

Database

0176-second-highest-salary
0177-nth-highest-salary
1527-patients-with-a-condition

Quickselect

0347-top-k-frequent-elements