LeetCode

LeetCode problem solutions in Java.

LeetCode Topics

Math

0007-reverse-integer
0009-palindrome-number
0048-rotate-image
0069-sqrtx
0189-rotate-array
0231-power-of-two
0268-missing-number
0342-power-of-four
0367-valid-perfect-square
0628-maximum-product-of-three-numbers
1013-fibonacci-number
1444-number-of-steps-to-reduce-a-number-to-zero
1635-number-of-good-pairs

Binary Search

0033-search-in-rotated-sorted-array
0034-find-first-and-last-position-of-element-in-sorted-array
0035-search-insert-position
0069-sqrtx
0153-find-minimum-in-rotated-sorted-array
0162-find-peak-element
0167-two-sum-ii-input-array-is-sorted
0268-missing-number
0287-find-the-duplicate-number
0367-valid-perfect-square
0374-guess-number-higher-or-lower
0540-single-element-in-a-sorted-array
0792-binary-search
0882-peak-index-in-a-mountain-array
0907-koko-eating-bananas

Array

0001-two-sum
0015-3sum
0018-4sum
0026-remove-duplicates-from-sorted-array
0031-next-permutation
0033-search-in-rotated-sorted-array
0034-find-first-and-last-position-of-element-in-sorted-array
0035-search-insert-position
0048-rotate-image
0053-maximum-subarray
0054-spiral-matrix
0073-set-matrix-zeroes
0075-sort-colors
0118-pascals-triangle
0121-best-time-to-buy-and-sell-stock
0128-longest-consecutive-sequence
0136-single-number
0153-find-minimum-in-rotated-sorted-array
0162-find-peak-element
0167-two-sum-ii-input-array-is-sorted
0169-majority-element
0189-rotate-array
0217-contains-duplicate
0229-majority-element-ii
0268-missing-number
0283-move-zeroes
0287-find-the-duplicate-number
0414-third-maximum-number
0448-find-all-numbers-disappeared-in-an-array
0485-max-consecutive-ones
0540-single-element-in-a-sorted-array
0560-subarray-sum-equals-k
0628-maximum-product-of-three-numbers
0792-binary-search
0882-peak-index-in-a-mountain-array
0907-koko-eating-bananas
1482-how-many-numbers-are-smaller-than-the-current-number
1528-kids-with-the-greatest-number-of-candies
1580-shuffle-the-array
1635-number-of-good-pairs
1651-shuffle-string
1791-richest-customer-wealth
1878-check-if-array-is-sorted-and-rotated
2271-rearrange-array-elements-by-sign

Matrix

0048-rotate-image
0054-spiral-matrix
0073-set-matrix-zeroes
1791-richest-customer-wealth

Hash Table

0001-two-sum
0073-set-matrix-zeroes
0128-longest-consecutive-sequence
0169-majority-element
0217-contains-duplicate
0229-majority-element-ii
0268-missing-number
0448-find-all-numbers-disappeared-in-an-array
0560-subarray-sum-equals-k
1482-how-many-numbers-are-smaller-than-the-current-number
1635-number-of-good-pairs

Counting

0169-majority-element
0229-majority-element-ii
1635-number-of-good-pairs

Sorting

0015-3sum
0018-4sum
0075-sort-colors
0169-majority-element
0217-contains-duplicate
0229-majority-element-ii
0268-missing-number
0414-third-maximum-number
0628-maximum-product-of-three-numbers
1482-how-many-numbers-are-smaller-than-the-current-number

Counting Sort

1482-how-many-numbers-are-smaller-than-the-current-number

Two Pointers

0015-3sum
0018-4sum
0026-remove-duplicates-from-sorted-array
0031-next-permutation
0075-sort-colors
0125-valid-palindrome
0167-two-sum-ii-input-array-is-sorted
0189-rotate-array
0283-move-zeroes
0287-find-the-duplicate-number
0344-reverse-string
2271-rearrange-array-elements-by-sign

Bit Manipulation

0136-single-number
0231-power-of-two
0268-missing-number
0287-find-the-duplicate-number
0342-power-of-four
1444-number-of-steps-to-reduce-a-number-to-zero

String

0125-valid-palindrome
0344-reverse-string
1651-shuffle-string

Interactive

0374-guess-number-higher-or-lower

Recursion

0231-power-of-two
0342-power-of-four
1013-fibonacci-number

Dynamic Programming

0053-maximum-subarray
0118-pascals-triangle
0121-best-time-to-buy-and-sell-stock
1013-fibonacci-number

Memoization

1013-fibonacci-number

Divide and Conquer

0053-maximum-subarray
0169-majority-element

Simulation

0054-spiral-matrix
2271-rearrange-array-elements-by-sign

Union Find

0128-longest-consecutive-sequence

Prefix Sum

0560-subarray-sum-equals-k