leetcode-problems

LeetCode Topics

Array

0001-two-sum
0015-3sum
0049-group-anagrams
0088-merge-sorted-array
0121-best-time-to-buy-and-sell-stock
0169-majority-element
0189-rotate-array
0217-contains-duplicate
0219-contains-duplicate-ii
0229-majority-element-ii
0239-sliding-window-maximum
0268-missing-number
0283-move-zeroes
0485-max-consecutive-ones
0496-next-greater-element-i
0560-subarray-sum-equals-k
0941-sort-array-by-parity
0958-sort-array-by-parity-ii
1019-squares-of-a-sorted-array
1112-find-words-that-can-be-formed-by-characters
1319-unique-number-of-occurrences
1392-find-the-difference-of-two-arrays
1580-shuffle-the-array
1603-running-sum-of-1d-array
1635-number-of-good-pairs
1802-number-of-students-unable-to-eat-lunch
1833-find-the-highest-altitude
2058-concatenation-of-array
2137-final-value-of-variable-after-performing-operations
2265-partition-array-according-to-given-pivot
2502-sort-the-people
2707-merge-two-2d-arrays-by-summing-values
3206-find-common-elements-between-two-arrays
3501-delete-nodes-from-linked-list-present-in-array

Prefix Sum

0560-subarray-sum-equals-k
1603-running-sum-of-1d-array
1833-find-the-highest-altitude

String

0020-valid-parentheses
0049-group-anagrams
0125-valid-palindrome
0242-valid-anagram
0344-reverse-string
0345-reverse-vowels-of-a-string
0392-is-subsequence
0412-fizz-buzz
0451-sort-characters-by-frequency
0567-permutation-in-string
0680-valid-palindrome-ii
0782-jewels-and-stones
0812-rotate-string
0957-minimum-add-to-make-parentheses-valid
1112-find-words-that-can-be-formed-by-characters
1128-remove-all-adjacent-duplicates-in-string
1371-minimum-remove-to-make-valid-parentheses
1472-increasing-decreasing-string
1567-maximum-number-of-vowels-in-a-substring-of-given-length
1666-make-the-string-great
1894-merge-strings-alternately
1960-check-if-the-sentence-is-pangram
1987-substrings-of-size-three-with-distinct-characters
2128-reverse-prefix-of-word
2137-final-value-of-variable-after-performing-operations
2502-sort-the-people

Simulation

0412-fizz-buzz
1802-number-of-students-unable-to-eat-lunch
2058-concatenation-of-array
2137-final-value-of-variable-after-performing-operations
2265-partition-array-according-to-given-pivot

Hash Table

0001-two-sum
0049-group-anagrams
0141-linked-list-cycle
0142-linked-list-cycle-ii
0160-intersection-of-two-linked-lists
0169-majority-element
0217-contains-duplicate
0219-contains-duplicate-ii
0229-majority-element-ii
0242-valid-anagram
0268-missing-number
0451-sort-characters-by-frequency
0496-next-greater-element-i
0560-subarray-sum-equals-k
0567-permutation-in-string
0782-jewels-and-stones
1112-find-words-that-can-be-formed-by-characters
1319-unique-number-of-occurrences
1392-find-the-difference-of-two-arrays
1472-increasing-decreasing-string
1635-number-of-good-pairs
1960-check-if-the-sentence-is-pangram
1987-substrings-of-size-three-with-distinct-characters
2502-sort-the-people
2707-merge-two-2d-arrays-by-summing-values
3206-find-common-elements-between-two-arrays
3501-delete-nodes-from-linked-list-present-in-array

Math

0050-powx-n
0189-rotate-array
0231-power-of-two
0268-missing-number
0412-fizz-buzz
1013-fibonacci-number
1411-convert-binary-number-in-a-linked-list-to-integer
1635-number-of-good-pairs
2383-add-two-integers

Counting

0169-majority-element
0229-majority-element-ii
0451-sort-characters-by-frequency
1112-find-words-that-can-be-formed-by-characters
1472-increasing-decreasing-string
1635-number-of-good-pairs
1987-substrings-of-size-three-with-distinct-characters

Two Pointers

0015-3sum
0019-remove-nth-node-from-end-of-list
0088-merge-sorted-array
0125-valid-palindrome
0141-linked-list-cycle
0142-linked-list-cycle-ii
0160-intersection-of-two-linked-lists
0189-rotate-array
0283-move-zeroes
0344-reverse-string
0345-reverse-vowels-of-a-string
0392-is-subsequence
0567-permutation-in-string
0680-valid-palindrome-ii
0908-middle-of-the-linked-list
0941-sort-array-by-parity
0958-sort-array-by-parity-ii
1019-squares-of-a-sorted-array
1894-merge-strings-alternately
2128-reverse-prefix-of-word
2265-partition-array-according-to-given-pivot
2707-merge-two-2d-arrays-by-summing-values

Sorting

0015-3sum
0049-group-anagrams
0088-merge-sorted-array
0169-majority-element
0217-contains-duplicate
0229-majority-element-ii
0242-valid-anagram
0268-missing-number
0451-sort-characters-by-frequency
0941-sort-array-by-parity
0958-sort-array-by-parity-ii
1019-squares-of-a-sorted-array
2502-sort-the-people

Linked List

0019-remove-nth-node-from-end-of-list
0021-merge-two-sorted-lists
0083-remove-duplicates-from-sorted-list
0141-linked-list-cycle
0142-linked-list-cycle-ii
0160-intersection-of-two-linked-lists
0203-remove-linked-list-elements
0206-reverse-linked-list
0908-middle-of-the-linked-list
1411-convert-binary-number-in-a-linked-list-to-integer
3501-delete-nodes-from-linked-list-present-in-array

Recursion

0021-merge-two-sorted-lists
0050-powx-n
0203-remove-linked-list-elements
0206-reverse-linked-list
0231-power-of-two
1013-fibonacci-number

Bit Manipulation

0231-power-of-two
0268-missing-number

Dynamic Programming

0121-best-time-to-buy-and-sell-stock
0392-is-subsequence
1013-fibonacci-number

Stack

0020-valid-parentheses
0155-min-stack
0225-implement-stack-using-queues
0232-implement-queue-using-stacks
0496-next-greater-element-i
0957-minimum-add-to-make-parentheses-valid
1128-remove-all-adjacent-duplicates-in-string
1371-minimum-remove-to-make-valid-parentheses
1666-make-the-string-great
1802-number-of-students-unable-to-eat-lunch
2128-reverse-prefix-of-word

String Matching

0812-rotate-string

Monotonic Stack

0496-next-greater-element-i

Binary Search

0268-missing-number

Heap (Priority Queue)

0239-sliding-window-maximum
0451-sort-characters-by-frequency

Bucket Sort

0451-sort-characters-by-frequency

Divide and Conquer

0169-majority-element

Memoization

1013-fibonacci-number

Greedy

0680-valid-palindrome-ii
0957-minimum-add-to-make-parentheses-valid

Design

0155-min-stack
0225-implement-stack-using-queues
0232-implement-queue-using-stacks
0969-number-of-recent-calls

Queue

0225-implement-stack-using-queues
0232-implement-queue-using-stacks
0239-sliding-window-maximum
0969-number-of-recent-calls
1802-number-of-students-unable-to-eat-lunch

Data Stream

0969-number-of-recent-calls

Sliding Window

0219-contains-duplicate-ii
0239-sliding-window-maximum
0567-permutation-in-string
1567-maximum-number-of-vowels-in-a-substring-of-given-length
1987-substrings-of-size-three-with-distinct-characters

Monotonic Queue

0239-sliding-window-maximum