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Professor solves 240 computer science exam problems in 4 hours [video]

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Re: Professor solves 240 computer science exam problems in 4 hours [video]

#31

Post by crote »

LockAndLol wrote: post #28

My CS exams in Europe and Australia involved calculations, proving stuff and applying knowledge to find the solution without a list of possible answers. Multiple choice questions at this level have always confused me and seemed like a really inept way of testing understanding (if they test understanding at all). I was fully expecting to see an implementation of a red-black tree, the use of software patterns, question…

Yeah, but that's much harder to grade.

The main benefit of multiple-choice is that grading is instant. There is no ambiguity, no half points.

I completely agree that tests like this should not exist, but sadly they do. Even in Europe bachelor's courses seem to be slowly shifting towards this.

Re: Professor solves 240 computer science exam problems in 4 hours [video]

#32

Post by jimhefferon »

har33sh wrote: post #26
jimhefferon wrote: post #9

Anyone know if these questions are freely available?

https://gateoverflow.in/categories Questions are categorized based on the subjects, I used this while preparing for GATE in 2015/2016.

Thank you. I was unclear. I meant licensed under some Free license. (I'm writing a Theory of Computation book that is Free and incorporating some of this material is attractive.)

The web site for IIT Delhi didn't say, that I could find.

Re: Professor solves 240 computer science exam problems in 4 hours [video]

#33

Post by bo1024 »

atum47 wrote: post #14

I admit that I struggled with regular languages, I didn't fail the class or anything, but as soon as I was done with it, never looked back. I thought about doing a Turing machine in JavaScript but I never actually did it. I wonder if people that retains all that information use it everyday, that's why they retain it. Thing I don't use in real life, like propositional logic, regular languages, automatas... I can barel…

Teaching a course on it regularly would really help keep it fresh.

Re: Professor solves 240 computer science exam problems in 4 hours [video]

#34

Post by atum47 »

kevmo314 wrote: post #20
atum47 wrote: post #14

I admit that I struggled with regular languages, I didn't fail the class or anything, but as soon as I was done with it, never looked back. I thought about doing a Turing machine in JavaScript but I never actually did it. I wonder if people that retains all that information use it everyday, that's why they retain it. Thing I don't use in real life, like propositional logic, regular languages, automatas... I can barel…

But despite not using it every day, you'd probably be able to refresh on it pretty quickly. I've found that to be the real value for a lot of the courses I took. Sure, I don't actively remember the content or use it daily, but occasionally something reminds me of something I learned. Then, it's a quick wiki page away from me understanding and using it. Contrast that with some devs I've worked with who haven't seen su…

on the interview for the job I have right now, they asked me a lot about design patterns. I took a class on that and implemented a lot of them in Java. Factory, Facade, Visitor, Singleton... Never used them again after college, ask me about it, I think I would be able to explain Factory and Singleton from the top of my head, the rest... gone!!!

I guess what I'm trying to say is that I would love to be that guy with a lot of information in the head, that can casually drop statics formulas and math concepts in a conversation, but that's not the case for my. At least for a lot of topics.

Watching the videos made me think about that. Starting a live video and answering 240 questions on several topics likes it's no big deal. Haha

Re: Professor solves 240 computer science exam problems in 4 hours [video]

#35

Post by atum47 »

bo1024 wrote: post #33
atum47 wrote: post #14

I admit that I struggled with regular languages, I didn't fail the class or anything, but as soon as I was done with it, never looked back. I thought about doing a Turing machine in JavaScript but I never actually did it. I wonder if people that retains all that information use it everyday, that's why they retain it. Thing I don't use in real life, like propositional logic, regular languages, automatas... I can barel…

Teaching a course on it regularly would really help keep it fresh.

I guess. I took a look at a test we have to take here in Brazil, if I want to get a master's degree. no way I can score high enough without studying for a few weeks. Calculus, statics, propositional logic...

When looking at the test I thought "man, I learned this in college, I should know that" but my brain was like "forget that, let's watch something funny on youtube"

Re: Professor solves 240 computer science exam problems in 4 hours [video]

#36

Post by qppo »

crote wrote: post #29
globular-toast wrote: post #22

Earlier quoted context omitted.

I guess this is a bit like the Someone Else's Problem phenomenon. Nobody needs to know about compilers, operating systems or analysis of algorithms because Somebody Else will deal with those things.

Are they really, though? I've followed a few courses on this, and they all focus on the mathematical background of it. Sure, it's neat to be able to prove some stuff about a toy language, but what does it really teach you? "Regular expressions" in most programming languages are not regular. A lot of programming languages aren't even context-free. Heck, C++ templates are Turing complete! Does anyone care? Not really.…

Academic research and education is normally focused on silo'd content and not holistic system design. To use your example, a parser that gracefully handles bad input is a completely different region of study than simple parsing/grammars. It's outside the context.

That does not mean that academia does not cover the topic, you just probably wouldn't get to it in an undergraduate course on (frankly trivial) compilers and parsers. If you read into research on things like semantic fuzzing, the slow death of batch compilers, and the various error propagation mechanisms out there from PL researchers you'd see those topics bring up lively academic discussions.

Academia lags in many ways behind practical designs because they aren't governed by deadlines and market realities, but they lead in many others precisely because ideas aren't constrained and they can focus on things that don't have immediate value to markets. It's not wise to discount an entire domain of expertise and culture of development just because it exists in a different context than professional engineering, particularly when we owe our entire industry to the efforts of academics in the first place.

Re: Professor solves 240 computer science exam problems in 4 hours [video]

#37

Post by dazhbog »

Watched a bit as I never came across these terms.. Staring at the wikipedia page of "Regular language" and I still dont get what is the purpose of this.

Anyone, not in academia preferably, using this for practical applications? What ARE the practical applications?

Re: Professor solves 240 computer science exam problems in 4 hours [video]

#39

Post by feanaro »

dazhbog wrote: post #37

Watched a bit as I never came across these terms.. Staring at the wikipedia page of "Regular language" and I still dont get what is the purpose of this. Anyone, not in academia preferably, using this for practical applications? What ARE the practical applications?

You've probably heard of regex, also known as regular expressions. Regex is at its core (before you add support for advanced stuff like backreferences) a generic way of defining an arbitrary regular language. Each regular expression corresponds to a deterministic finite automaton (DFA) which detects strings belonging to that language.

EDIT, to add a bit more:

The theory behind regular languages allows you to design a regex system, to know its limitations and to be able to determine whether a language can be matched by a regex or it requires a more powerful model.

It can definitely be useful to think in terms of such theoretical constructs when approaching new problems, but it takes some getting used to before it can become productive. For this reason, I think the cost/benefit ratio of learning this for someone completely new to it can vary. It's probably not always worth it in all settings, but it certainly has practical merit.

Re: Professor solves 240 computer science exam problems in 4 hours [video]

#40

Post by bo1024 »

juskrey wrote: post #13

Skimming through the pages on the video, it shows vividly how far away academia is from real life problems.

I'm biased, but this perspective hits a pet peeve for me. These are introductory theory of computation problems - of course they aren't real-life problems! Would we make the same complaint against a mathematics exam on group theory or real analysis? Does a question like "prove that the kernel of a homomorphism is a normal subgroup" show how far academia is from real-life problems? But probably the people responsible for inventing half the technology we use in daily life had to solve that problem at some point and R&D departments would be scared to hire them if they hadn't.

Knowledge, especially in mathematics, is not a buffet; it's a pyramid. Wecan't hope for society to build programming languages like Haskell or Rust without teaching people the knowledge base that rests on regular languages and pushdown automata and so on.

That said, this is definitely one of the most esoteric topics in an undergrad CS curriculum and many universities are making it optional, for theory-inclined students only.

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