Week 1 of Algorithms Part II. Graphs

I finished Algorithms 1 from Coursera a couple of weeks ago, and this week, I just finished the first weeek's work for Algorithms II from Coursera.

I tried to make the most of my time off between the two classes. I worked on an open source project, did some reading about building web applications and tried to study some other things. During this time off, I realized that I prefer structured classes. They help me to stay focused on the subject of study. With that said, I have to continue to push myself to focus on the material and my deep understanding of it, instead of allowing myself to be satisfied with simply getting the correct answers for the course.

I think some ways to improve my understanding will be to review and participate in the Coursera discussion forums. This gives me a chance to see how others (different from the course instructors) are thinking about the material. In the discussion forum, I can have the chance to approach things as a teacher, which will also help me to understand the material better.

So, onto my thoughts on week 1 of Algorithms 2.

This week, we went over undirected and directed graphs. Using breadth first and depth first searches, we were able to solve some possibly tricky problems like topological sort and finding strong components in directed graphs. The takeaway for me is to get very comfortable with depth and breadth first searches and to have a good mental image of what we get from each. With these two tools you can have a good chance of answering a question. Interestingly, it's a bit difficult to know at first glance how fast you might be able to solve a given problem. It's a lot less intuitive than guessing calculation times of sorting algorithms.

The lectures did an OK job of presenting the material. There were a few demos that you should watch (not just read through). The exercises were rather pain free. They asked you to trace through the steps of things like breadth first and depth first search.

The programming assignment, similar to ones in Algorithm I, asked us to work with existing implementations (this week, a directed graph) instead of writing an implementation on our own. I guess re-writing an implementation on my own can be part of my own self studying. The most time consuming part of this project was understanding the requirements (can there be multiple terms in a synset, is a word unique across synsets, etc ...) After I figured out what the requirements were, it was pretty straightforward to use the provided directed graph class to finish. I'm not sure if it really improved my understanding of Graphs, but at least it didn't take too much time.