- Linked Lists (insertion, deletion, search, reverse):
- Singly linked list
- Doubly linked list
- Stacks (push, pop, peek):
- Using arrays/slices
- Using linked lists
- Queues:
- Using arrays/slices
- Using linked lists
- Hash Tables (insert, delete, search)
- Basic implementation
- Trees (insertion, deletion, traversal: inorder, preorder, postorder):
- Binary tree
- Binary Search Tree (BST)
- AVL tree (self-balancing)
- Heaps (insert, delete, extract-min/max):
- Min-Heap
- Max-Heap
- Graphs (add edge, remove edge, search: DFS, BFS):
- Adjacency matrix
- Adjacency list
- Sorting Algorithms:
- Bubble sort
- Selection sort
- Insertion sort
- Merge sort
- Quick sort
- Heap sort
- Searching Algorithms:
- Linear search
- Binary search
- Graph Algorithms:
- Depth-First Search (DFS)
- Breadth-First Search (BFS)
- Dijkstra’s algorithm (shortest path)
- Floyd-Warshall algorithm (all pairs shortest path)
- Dynamic Programming:
- Fibonacci sequence
- Longest Common Subsequence (LCS)
- Knapsack problem
- Coin change problem
- Backtracking:
- N-Queens problem
- Sudoku solver
- Subset sum problem
| Number | Title | Difficulty | Solution |
|---|---|---|---|
| 1 | Two Sum | Easy | two-sum |
| 3 | Longest Substring Without Repeating Characters | Medium | longest-substring-without-repeating-characters |
| 12 | Integer to Roman | Medium | integer-to-roman |
| 13 | Roman to Integer | Easy | roman-to-integer |
| 14 | Longest Common Prefix | Easy | longest-common-prefix |
| 19 | Remove Nth Node From End of List | Medium | remove-nth-node-from-end-of-list |
| 20 | Valid Parentheses | Easy | valid-parentheses |
| 22 | Generate Parentheses | Medium | generate-parentheses |
| 26 | Remove Duplicates from Sorted Array | Easy | remove-duplicates-from-sorted-array |
| 27 | Remove Element | Easy | remove-element |
| 28 | Find the Index of the First Occurrence in a String | Easy | find-the-index-of-the-first-occurrence-in-a-string |
| 36 | Valid Sudoku | Medium | valid-sudoku |
| 49 | Group Anagrams | Medium | group-anagrams |
| 58 | Length of Last Word | Easy | length-of-last-word |
| 80 | Remove Duplicates from Sorted Array II | Medium | remove-duplicates-from-sorted-array-ii |
| 88 | Merge Sorted Array | Easy | merge-sorted-array |
| 121 | Best Time to Buy and Sell Stock | Easy | best-time-to-buy-and-sell-stock |
| 122 | Best Time to Buy and Sell Stock II | Medium | best-time-to-buy-and-sell-stock-ii |
| 125 | Valid Palindrome | Easy | valid-palindrome |
| 128 | Longest Consecutive Sequence | Medium | longest-consecutive-sequence |
| 136 | Single Number | Easy | single-number |
| 141 | Linked List Cycle | Easy | linked-list-cycle |
| 142 | Linked List Cycle II | Medium | linked-list-cycle-ii |
| 150 | Evaluate Reverse Polish Notation | Medium | evaluate-reverse-polish-notation |
| 155 | Min Stack | Medium | min-stack |
| 160 | Intersection of Two Linked Lists | Easy | intersection-of-two-linked-lists |
| 169 | Majority Element | Easy | majority-element |
| 170 | Two Sum III - Data structure design | Easy | two-sum-iii-data-structure-design |
| 189 | Rotate Array | Medium | rotate-array |
| 202 | Happy Number | Easy | happy-number |
| 205 | Isomorphic Strings | Easy | isomorphic-strings |
| 217 | Contains Duplicate | Easy | contains-duplicate |
| 219 | Contains Duplicate II | Easy | contains-duplicate-ii |
| 238 | Product of Array Except Self | Medium | product-of-array-except-self |
| 242 | Valid Anagram | Easy | valid-anagram |
| 249 | Group Shifted Strings | Medium | group-shifted-strings |
| 271 | Encode and Decode Strings | Medium | encode-and-decode-strings |
| 288 | Unique Word Abbreviation | Medium | unique-word-abbreviation |
| 347 | Top K Frequent Elements | Medium | top-k-frequent-elements |
| 350 | Intersection of Two Arrays II | Easy | intersection-of-two-arrays-ii |
| 359 | Logger Rate Limiter | Easy | logger-rate-limiter |
| 380 | Insert Delete GetRandom O(1) | Medium | insert-delete-getrandom-o1 |
| 383 | Ransom Note | Easy | ransom-note |
| 387 | First Unique Character in a String | Easy | first-unique-character-in-a-string |
| 412 | Fizz Buzz | Easy | fizz-buzz |
| 454 | 4Sum II | Medium | 4sum-ii |
| 599 | Minimum Index Sum of Two Lists | Easy | minimum-index-sum-of-two-lists |
| 652 | Find Duplicate Subtrees | Medium | find-duplicate-subtrees |
| 707 | Design Linked List | Medium | design-linked-list |
| 739 | Daily Temperatures | Medium | daily-temperatures |
| 771 | Jewels and Stones | Easy | jewels-and-stones |
| 876 | Middle of the Linked List | Easy | middle-of-the-linked-list |
| 1342 | Number of Steps to Reduce a Number to Zero | Easy | richest-customer-wealth |
| 1480 | Running Sum of 1d Array | Easy | running-sum-of-1d-array |
| 1672 | Richest Customer Wealth | Easy | richest-customer-wealth |