The first topic came up from last week was recursively defined functions. It is not on the midterm but I am a fan of that because it involves relative more algebra calculations instead of more analyzing. Basically, it is a kind of questions which gives you a defined, recursive function, then it asks you to prove a statement depends on the given recursive function by unwinding and induction step.
However, a question came up my mind when I was focusing on the lecture. "Which are not proper definition of functions?" By observation, the examples given in lecture and tutorial are all proper. I summarized about it somehow but also looked up from online textbook. Mostly, my summary matched book's.
- the induction step has to define value of a function properly for all n.
- no term to make function circular
- define f(n) in terms of the value of f at smaller statement
* it is such a good way to summarize the points of views by self-observation which makes me analyze more than learn from read.
Also, more importantly, divid and conquer recurrences and Master theorem has been taught in the lecture. Once the lecture mentioned about the time complexity, Big O stuff that I learned from CSC165 came up my mind. Since lectures was running fast and I was kinda lost, I reviewed textbook which was really helpful. I realized the reason that I didn't do well in CSC165 at this part was that I wasn't fully understand the time complexity and just followed the steps of proof. I dig more about understanding and reasoning this year not only by textbook but also web sources. Practice makes me not only think fast but deeply.
I'd like to share some interesting problems that I collect from other sources next time after I finish my A2.