Leetcode_by_prema

A collection of LeetCode questions to ace the coding interview! - Created using LeetHub v2

LeetCode Topics

Array

0001-two-sum
0004-median-of-two-sorted-arrays
0036-valid-sudoku
0037-sudoku-solver
0039-combination-sum
0040-combination-sum-ii
0049-group-anagrams
0051-n-queens
0055-jump-game
0075-sort-colors
0090-subsets-ii
0106-construct-binary-tree-from-inorder-and-postorder-traversal
0108-convert-sorted-array-to-binary-search-tree
0496-next-greater-element-i
0540-single-element-in-a-sorted-array
0646-maximum-length-of-pair-chain
0882-peak-index-in-a-mountain-array
0948-sort-an-array
1036-rotting-oranges
1985-maximum-subarray-min-product
2188-minimized-maximum-of-products-distributed-to-any-store
2195-time-needed-to-buy-tickets
2662-check-knight-tour-configuration

Hash Table

0001-two-sum
0003-longest-substring-without-repeating-characters
0036-valid-sudoku
0037-sudoku-solver
0049-group-anagrams
0106-construct-binary-tree-from-inorder-and-postorder-traversal
0138-copy-list-with-random-pointer
0141-linked-list-cycle
0142-linked-list-cycle-ii
0146-lru-cache
0387-first-unique-character-in-a-string
0496-next-greater-element-i

Database

0176-second-highest-salary
0177-nth-highest-salary
0178-rank-scores
0182-duplicate-emails
0183-customers-who-never-order
0577-employee-bonus
0584-find-customer-referee
0595-big-countries
1258-article-views-i
1908-recyclable-and-low-fat-products

Linked List

0002-add-two-numbers
0021-merge-two-sorted-lists
0025-reverse-nodes-in-k-group
0061-rotate-list
0092-reverse-linked-list-ii
0114-flatten-binary-tree-to-linked-list
0138-copy-list-with-random-pointer
0141-linked-list-cycle
0142-linked-list-cycle-ii
0146-lru-cache
0206-reverse-linked-list
0766-flatten-a-multilevel-doubly-linked-list
0908-middle-of-the-linked-list

Math

0002-add-two-numbers
0070-climbing-stairs

Recursion

0002-add-two-numbers
0021-merge-two-sorted-lists
0025-reverse-nodes-in-k-group
0206-reverse-linked-list

String

0003-longest-substring-without-repeating-characters
0014-longest-common-prefix
0028-find-the-index-of-the-first-occurrence-in-a-string
0032-longest-valid-parentheses
0049-group-anagrams
0058-length-of-last-word
0131-palindrome-partitioning
0151-reverse-words-in-a-string
0387-first-unique-character-in-a-string
0443-string-compression
0459-repeated-substring-pattern
1508-longest-happy-prefix

Two Pointers

0028-find-the-index-of-the-first-occurrence-in-a-string
0061-rotate-list
0075-sort-colors
0141-linked-list-cycle
0142-linked-list-cycle-ii
0151-reverse-words-in-a-string
0443-string-compression
0908-middle-of-the-linked-list

String Matching

0028-find-the-index-of-the-first-occurrence-in-a-string
0459-repeated-substring-pattern
1508-longest-happy-prefix

Sliding Window

0003-longest-substring-without-repeating-characters

Trie

0014-longest-common-prefix

Dynamic Programming

0032-longest-valid-parentheses
0055-jump-game
0070-climbing-stairs
0131-palindrome-partitioning
0646-maximum-length-of-pair-chain

Stack

0032-longest-valid-parentheses
0094-binary-tree-inorder-traversal
0114-flatten-binary-tree-to-linked-list
0155-min-stack
0225-implement-stack-using-queues
0232-implement-queue-using-stacks
0496-next-greater-element-i
0937-online-stock-span
1985-maximum-subarray-min-product

Matrix

0036-valid-sudoku
0037-sudoku-solver
1036-rotting-oranges
2662-check-knight-tour-configuration

Divide and Conquer

0004-median-of-two-sorted-arrays
0106-construct-binary-tree-from-inorder-and-postorder-traversal
0108-convert-sorted-array-to-binary-search-tree
0948-sort-an-array

Tree

0094-binary-tree-inorder-traversal
0102-binary-tree-level-order-traversal
0106-construct-binary-tree-from-inorder-and-postorder-traversal
0108-convert-sorted-array-to-binary-search-tree
0114-flatten-binary-tree-to-linked-list
0199-binary-tree-right-side-view
0222-count-complete-tree-nodes
0236-lowest-common-ancestor-of-a-binary-tree
0513-find-bottom-left-tree-value
0543-diameter-of-binary-tree
0799-minimum-distance-between-bst-nodes
1114-binary-search-tree-to-greater-sum-tree
1116-maximum-level-sum-of-a-binary-tree

Binary Search Tree

0004-median-of-two-sorted-arrays
0108-convert-sorted-array-to-binary-search-tree
0222-count-complete-tree-nodes
0540-single-element-in-a-sorted-array
0799-minimum-distance-between-bst-nodes
0882-peak-index-in-a-mountain-array
1114-binary-search-tree-to-greater-sum-tree
2188-minimized-maximum-of-products-distributed-to-any-store

Binary Tree

0094-binary-tree-inorder-traversal
0102-binary-tree-level-order-traversal
0106-construct-binary-tree-from-inorder-and-postorder-traversal
0108-convert-sorted-array-to-binary-search-tree
0114-flatten-binary-tree-to-linked-list
0199-binary-tree-right-side-view
0222-count-complete-tree-nodes
0236-lowest-common-ancestor-of-a-binary-tree
0513-find-bottom-left-tree-value
0543-diameter-of-binary-tree
0799-minimum-distance-between-bst-nodes
1114-binary-search-tree-to-greater-sum-tree
1116-maximum-level-sum-of-a-binary-tree

Greedy

0055-jump-game
0646-maximum-length-of-pair-chain
2188-minimized-maximum-of-products-distributed-to-any-store

Sorting

0049-group-anagrams
0075-sort-colors
0646-maximum-length-of-pair-chain
0948-sort-an-array

Memoization

0070-climbing-stairs

Bit Manipulation

0090-subsets-ii
0222-count-complete-tree-nodes

Rolling Hash

1508-longest-happy-prefix

Hash Function

1508-longest-happy-prefix

Backtracking

0037-sudoku-solver
0039-combination-sum
0040-combination-sum-ii
0051-n-queens
0090-subsets-ii
0131-palindrome-partitioning

Depth-First Search

0094-binary-tree-inorder-traversal
0114-flatten-binary-tree-to-linked-list
0199-binary-tree-right-side-view
0236-lowest-common-ancestor-of-a-binary-tree
0513-find-bottom-left-tree-value
0543-diameter-of-binary-tree
0766-flatten-a-multilevel-doubly-linked-list
0799-minimum-distance-between-bst-nodes
1114-binary-search-tree-to-greater-sum-tree
1116-maximum-level-sum-of-a-binary-tree
2662-check-knight-tour-configuration

Breadth-First Search

0102-binary-tree-level-order-traversal
0199-binary-tree-right-side-view
0513-find-bottom-left-tree-value
0799-minimum-distance-between-bst-nodes
1036-rotting-oranges
1116-maximum-level-sum-of-a-binary-tree
2662-check-knight-tour-configuration

Simulation

2195-time-needed-to-buy-tickets
2662-check-knight-tour-configuration

Heap (Priority Queue)

0948-sort-an-array

Merge Sort

0948-sort-an-array

Bucket Sort

0948-sort-an-array

Radix Sort

0948-sort-an-array

Counting Sort

0387-first-unique-character-in-a-string
0948-sort-an-array

Doubly-Linked List

0146-lru-cache
0766-flatten-a-multilevel-doubly-linked-list

Design

0146-lru-cache
0155-min-stack
0225-implement-stack-using-queues
0232-implement-queue-using-stacks
0937-online-stock-span

Queue

0225-implement-stack-using-queues
0232-implement-queue-using-stacks
0387-first-unique-character-in-a-string
2195-time-needed-to-buy-tickets

Monotonic Stack

0496-next-greater-element-i
0937-online-stock-span
1985-maximum-subarray-min-product

Prefix Sum

1985-maximum-subarray-min-product

Data Stream

0937-online-stock-span