1. Data Structures & Algorithms

The following is a long list of topics. If you're preparing to interview at a top tech company and don't have much time (<2 months), just go over the essentials.

Coding Challenges

Do all the Leetcode problems from the "Google Problems" section. Don't worry if you're not applying to Google. And don't be a cry baby. Just do them all and you'll be in a better shape.

Data Structures

Essentials - You're screwed if you don't know these.

Be able to implement any of these from scratch

1. Dynamic Array (Notes)

2. Linked List (Notes)

3. Stack & Queue (Notes)

4. Hash Tables (Notes)

5. Binary Search Tree (Notes)

6. BinaryHeaps (Notes)

7. Graphs (Notes)

8. Trie (Notes)

9. Priority Queue

Advanced - Ignore if you don't have time.

1. Red-Black Tree (Notes)

2. AVL Tree (Notes)

3. Splay Tree (Notes)

4. Radix trees (Notes)

5. Suffix Tree

6. B-Tree (Notes)

7. Fibonacci Heap (Notes)

8. Fenwick tree

Algorithms

Essentials - You're screwed if you don't know these.

Try implementing these.

1. Bit Manipulation & Numbers (Notes) - Unsigned vs signed numbers. Negative and positive number representation. Know how add and subtract works.

2. Stability in Sorting

3. Mergesort

4. Quicksort

5. Heapsort - Sort it in-place to get O(1) space

6. Binary Search

7. Selections - Kth Smallest Elements (Sort, QuickSelect, Mediums of Mediums) - Implement all three ways

8. Permutations (Notes)

9. Subsets

10. BFS Graph

11. DFS Graph

12. Dijkstra's Algorithm

13. Tree Traversals - BFS, DFS (in-order, pre-order, post-order): Implement Recursive and Iterative

14. External Sort - No implementation

15. NP-Complete (Video) - just know the concept

16. Topological Sort

17. Detect cycle in an undirected graph

18. Detect cycle in a directed graph

19. Count connected components in graph

20. Find strongly connected components in graph

Advanced - Ignore if you don't have time.

1. Bellman Ford

2. Floyd Warshall

3. Ford Fulkerson

4. Disjoint Set

5. What is a Spanning tree?

6. Minimum Spanning Tree (Kruskal and Prim)

7. A*

8. Radix Sort —— Didn’t cover in class

9. General Sorting Algorithms (Notes) - Bubble sort, insertion sort, etc.

10. Explain bipartite graph (how do you check if graph is bipartite?)

11. Do Traveling Salesperson and other NP problems