Lists
4 pagesArrayList and LinkedList built by hand, then the pointer patterns and the stack/queue idioms interviewers reach for.
- ArrayListLesson
- LinkedListLesson
- Linked list patterns13 sections
- Stacks & Queues14 sections
02 / DATA STRUCTURES
Data Structures
Lists, hashing, trees and graphs as one progression. Each structure gets the Holt lesson that builds it from scratch, and where a prep sheet exists it follows with the interview problems that structure unlocks: linked-list pointer games, stack and queue idioms, hash-map counting, tree traversals, heaps, tries and graph search.
Start here
16 pages · 4 groups
Hashing
2 pagesHash maps as the universal counting tool, and Bloom filters for "probably seen it".
- Hash Maps11 sections
- Bloom FiltersLesson
Trees
8 pagesBinary search trees, AVL rotations, traversals, heaps, tries and the problem sheets for each.
- Binary Search TreeLesson
- AVL TreeLesson
- Depth-First Tree TraversalsLesson
- Breadth-First Tree TraversalsLesson
- Trees & BST patterns18 sections
- Heaps (priority queues)10 sections
- TriesLesson
- Trie patterns7 sections
Graphs
2 pagesGraph representations, BFS/DFS, topological sort, Dijkstra and union-find.
- GraphsLesson
- Graph patterns18 sections