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

LeetCode Topics

Tree

0094-binary-tree-inorder-traversal
0098-validate-binary-search-tree
0105-construct-binary-tree-from-preorder-and-inorder-traversal
0106-construct-binary-tree-from-inorder-and-postorder-traversal
0173-binary-search-tree-iterator
0222-count-complete-tree-nodes
0230-kth-smallest-element-in-a-bst
0235-lowest-common-ancestor-of-a-binary-search-tree
0236-lowest-common-ancestor-of-a-binary-tree
0450-delete-node-in-a-bst
0653-two-sum-iv-input-is-a-bst
0662-maximum-width-of-binary-tree
0701-insert-into-a-binary-search-tree
0863-all-nodes-distance-k-in-binary-tree
1008-construct-binary-search-tree-from-preorder-traversal

Depth-First Search

0094-binary-tree-inorder-traversal
0098-validate-binary-search-tree
0130-surrounded-regions
0200-number-of-islands
0207-course-schedule
0230-kth-smallest-element-in-a-bst
0235-lowest-common-ancestor-of-a-binary-search-tree
0236-lowest-common-ancestor-of-a-binary-tree
0547-number-of-provinces
0653-two-sum-iv-input-is-a-bst
0662-maximum-width-of-binary-tree
0733-flood-fill
0785-is-graph-bipartite
0863-all-nodes-distance-k-in-binary-tree
1020-number-of-enclaves

Binary Tree

0094-binary-tree-inorder-traversal
0098-validate-binary-search-tree
0105-construct-binary-tree-from-preorder-and-inorder-traversal
0106-construct-binary-tree-from-inorder-and-postorder-traversal
0173-binary-search-tree-iterator
0222-count-complete-tree-nodes
0230-kth-smallest-element-in-a-bst
0235-lowest-common-ancestor-of-a-binary-search-tree
0236-lowest-common-ancestor-of-a-binary-tree
0450-delete-node-in-a-bst
0653-two-sum-iv-input-is-a-bst
0662-maximum-width-of-binary-tree
0701-insert-into-a-binary-search-tree
0863-all-nodes-distance-k-in-binary-tree
1008-construct-binary-search-tree-from-preorder-traversal

String

0005-longest-palindromic-substring
0008-string-to-integer-atoi
0127-word-ladder
0151-reverse-words-in-a-string
0205-isomorphic-strings
0451-sort-characters-by-frequency
0796-rotate-string
0953-verifying-an-alien-dictionary
1021-remove-outermost-parentheses
1614-maximum-nesting-depth-of-the-parentheses
1781-sum-of-beauty-of-all-substrings
1903-largest-odd-number-in-string
2947-count-beautiful-substrings-i

Stack

0094-binary-tree-inorder-traversal
0173-binary-search-tree-iterator
1008-construct-binary-search-tree-from-preorder-traversal
1021-remove-outermost-parentheses
1614-maximum-nesting-depth-of-the-parentheses

Math

1903-largest-odd-number-in-string
2947-count-beautiful-substrings-i

Greedy

0621-task-scheduler
0846-hand-of-straights
1903-largest-odd-number-in-string

Hash Table

0105-construct-binary-tree-from-preorder-and-inorder-traversal
0106-construct-binary-tree-from-inorder-and-postorder-traversal
0127-word-ladder
0205-isomorphic-strings
0355-design-twitter
0451-sort-characters-by-frequency
0621-task-scheduler
0653-two-sum-iv-input-is-a-bst
0846-hand-of-straights
0863-all-nodes-distance-k-in-binary-tree
0953-verifying-an-alien-dictionary
1781-sum-of-beauty-of-all-substrings
2947-count-beautiful-substrings-i

Sorting

0451-sort-characters-by-frequency
0621-task-scheduler
0846-hand-of-straights

Heap (Priority Queue)

0023-merge-k-sorted-lists
0355-design-twitter
0451-sort-characters-by-frequency
0621-task-scheduler

Bucket Sort

0451-sort-characters-by-frequency

Counting

0451-sort-characters-by-frequency
0621-task-scheduler
1781-sum-of-beauty-of-all-substrings

Two Pointers

0005-longest-palindromic-substring
0151-reverse-words-in-a-string
0653-two-sum-iv-input-is-a-bst

String Matching

0796-rotate-string

Dynamic Programming

0005-longest-palindromic-substring
0542-01-matrix

Enumeration

2947-count-beautiful-substrings-i

Number Theory

2947-count-beautiful-substrings-i

Prefix Sum

2947-count-beautiful-substrings-i

Array

0105-construct-binary-tree-from-preorder-and-inorder-traversal
0106-construct-binary-tree-from-inorder-and-postorder-traversal
0130-surrounded-regions
0200-number-of-islands
0542-01-matrix
0621-task-scheduler
0733-flood-fill
0846-hand-of-straights
0953-verifying-an-alien-dictionary
0994-rotting-oranges
1008-construct-binary-search-tree-from-preorder-traversal
1020-number-of-enclaves
1584-min-cost-to-connect-all-points

Linked List

0023-merge-k-sorted-lists
0355-design-twitter

Design

0173-binary-search-tree-iterator
0355-design-twitter

Union-Find

0130-surrounded-regions
0200-number-of-islands
0547-number-of-provinces
0785-is-graph-bipartite
1020-number-of-enclaves
1584-min-cost-to-connect-all-points

Graph Theory

0207-course-schedule
0547-number-of-provinces
0785-is-graph-bipartite
1584-min-cost-to-connect-all-points

Minimum Spanning Tree

1584-min-cost-to-connect-all-points

Divide and Conquer

0023-merge-k-sorted-lists
0105-construct-binary-tree-from-preorder-and-inorder-traversal
0106-construct-binary-tree-from-inorder-and-postorder-traversal

Merge Sort

0023-merge-k-sorted-lists

Tournament Sort

0023-merge-k-sorted-lists

Breadth-First Search

0127-word-ladder
0130-surrounded-regions
0200-number-of-islands
0207-course-schedule
0542-01-matrix
0547-number-of-provinces
0653-two-sum-iv-input-is-a-bst
0662-maximum-width-of-binary-tree
0733-flood-fill
0785-is-graph-bipartite
0863-all-nodes-distance-k-in-binary-tree
0994-rotting-oranges
1020-number-of-enclaves

Binary Search

0222-count-complete-tree-nodes

Bit Manipulation

0222-count-complete-tree-nodes

Binary Search Tree

0098-validate-binary-search-tree
0173-binary-search-tree-iterator
0230-kth-smallest-element-in-a-bst
0235-lowest-common-ancestor-of-a-binary-search-tree
0450-delete-node-in-a-bst
0653-two-sum-iv-input-is-a-bst
0701-insert-into-a-binary-search-tree
1008-construct-binary-search-tree-from-preorder-traversal

Binary Lifting

0235-lowest-common-ancestor-of-a-binary-search-tree

Lowest Common Ancestor

0235-lowest-common-ancestor-of-a-binary-search-tree

Monotonic Stack

1008-construct-binary-search-tree-from-preorder-traversal

Iterator

0173-binary-search-tree-iterator

Matrix

0130-surrounded-regions
0200-number-of-islands
0542-01-matrix
0733-flood-fill
0994-rotting-oranges
1020-number-of-enclaves

Topological Sort

0207-course-schedule

Directed Acyclic Graph

0207-course-schedule

Bidirectional Search

0127-word-ladder

Graph Coloring

0785-is-graph-bipartite

Bipartite Graph

0785-is-graph-bipartite