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Optimizing a breadth-first search

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Re: Optimizing a breadth-first search

#21

Post by taeric »

hashkb wrote: post #19
taeric wrote: post #18

Earlier quoted context omitted.

I think you are using very rose colored glasses looking at the past. The best of the best could do that, likely. However, few could ever do things in seconds. Nor is there really any benefit in being able to solve something in seconds. Interestingly, to me, it seems our industry was dominated by people that got good at gluing things together. To a very large degree. We bemoan this when we talk about how much more res…

Nobody here would deny the business value of gluing APIs together. We're not asking for your empathy, either; but we are telling you the truth about the difference between where the bar was and where it is now. The idea that "computers are fast, my code just needs to work" is a really really horrible way to treat your users' devices. A whole host of similar ideas are now popular, and it's pretty obvious that it's bec…

I'd wager the bar wasn't as high back then as you think. Most people still wrote inefficient things. Lots of it. There is a hope that most of the inefficient things flat out stalled out due to needing to be much more frugal of resources, but I don't know of any data backing that.

So, seriously, do you have data showing that the bar is lower? Or are you just performing selection and survivor bias to get such a negative view? (Similarly, am I doing the same to get a positive view?)

My main qualm is people that seem to hold incoming folks to the bar that they have today, without acknowledging the growth that was necessary for some of that. As a parent, I fully know my children will be better at most everything than I am. In time. Same for most of the younger generation coming out of college into the industry. Most are or will be better than I am. Pretty much full stop.

Re: Optimizing a breadth-first search

#22

Post by duxup »

hashkb wrote: post #17
stcredzero wrote: post #15

Something has happened to Comp Sci programs over the past 3 decades. Based on what's too small a sample size (the graduates I've been interviewing in SF) it seems like a very large number of graduates from CS programs with 3.75 GPAs or above, can't do much more than glue together libraries, can't practically design a system on their own, and if ever confronted with a graph theory problem, can't do much more than name…

I clicked on this thread to make a sure-to-be-downvoted ironic comment along the lines of "this isn't appropriate content for HN based on community sentiment regarding whiteboard interviews and what kind of work we actually do at our jobs." There's a serious problem in the industry being driven by coding bootcamps; it's really sad to see universities being forced to stoop to compete.

"There's a serious problem in the industry being driven by coding bootcamps; it's really sad to see universities being forced to stoop to compete."

Is that really the case, universities are trying to compete with bootcamps? I don't see much in the way of signs of that.

Re: Optimizing a breadth-first search

#23

Post by Asooka »

hashkb wrote: post #19
taeric wrote: post #18

Earlier quoted context omitted.

I think you are using very rose colored glasses looking at the past. The best of the best could do that, likely. However, few could ever do things in seconds. Nor is there really any benefit in being able to solve something in seconds. Interestingly, to me, it seems our industry was dominated by people that got good at gluing things together. To a very large degree. We bemoan this when we talk about how much more res…

Nobody here would deny the business value of gluing APIs together. We're not asking for your empathy, either; but we are telling you the truth about the difference between where the bar was and where it is now. The idea that "computers are fast, my code just needs to work" is a really really horrible way to treat your users' devices. A whole host of similar ideas are now popular, and it's pretty obvious that it's bec…

Maybe the counterpoint should be that gluing things together should produce better optimised products. You could probably even charge for tools like that. Why should the programmer have to know the best data structures and algorithms if the computer can do it for them? We don't hand-optimise assembly any more either, except in very narrow cases.

Re: Optimizing a breadth-first search

#24

Post by stcredzero »

taeric wrote: post #18
stcredzero wrote: post #15

Something has happened to Comp Sci programs over the past 3 decades. Based on what's too small a sample size (the graduates I've been interviewing in SF) it seems like a very large number of graduates from CS programs with 3.75 GPAs or above, can't do much more than glue together libraries, can't practically design a system on their own, and if ever confronted with a graph theory problem, can't do much more than name…

I think you are using very rose colored glasses looking at the past. The best of the best could do that, likely. However, few could ever do things in seconds. Nor is there really any benefit in being able to solve something in seconds. Interestingly, to me, it seems our industry was dominated by people that got good at gluing things together. To a very large degree. We bemoan this when we talk about how much more res…

I think you are using very rose colored glasses looking at the past. The best of the best could do that, likely.

The fact that you are classifying actually learned something when we covered BFS/DFS Freshman year as being equivalent to "the best of the best" speaks volumes.

Re: Optimizing a breadth-first search

#25

Post by ball_of_lint »

stcredzero wrote: post #15

Something has happened to Comp Sci programs over the past 3 decades. Based on what's too small a sample size (the graduates I've been interviewing in SF) it seems like a very large number of graduates from CS programs with 3.75 GPAs or above, can't do much more than glue together libraries, can't practically design a system on their own, and if ever confronted with a graph theory problem, can't do much more than name…

3.75 is a very high bar. I don't pass that bar. At that point I'd expect to be filtering work ethic much more strongly than skill or talent.

There may be some grads that have the problems that you describe but there are also many that have those skills. Look at the ICPC regional contests. Many students competing are very highly skilled in algorithms and hacking things together quickly. That does not always make them good employees.

Re: Optimizing a breadth-first search

#26

Post by stcredzero »

taeric wrote: post #21
hashkb wrote: post #19

Earlier quoted context omitted.

Nobody here would deny the business value of gluing APIs together. We're not asking for your empathy, either; but we are telling you the truth about the difference between where the bar was and where it is now. The idea that "computers are fast, my code just needs to work" is a really really horrible way to treat your users' devices. A whole host of similar ideas are now popular, and it's pretty obvious that it's bec…

I'd wager the bar wasn't as high back then as you think. Most people still wrote inefficient things. Lots of it. There is a hope that most of the inefficient things flat out stalled out due to needing to be much more frugal of resources, but I don't know of any data backing that. So, seriously, do you have data showing that the bar is lower? Or are you just performing selection and survivor bias to get such a negativ…

I'd wager the bar wasn't as high back then as you think. Most people still wrote inefficient things. Lots of it.

Lots of those people who wrote inefficient things were the C students in Comp Sci. A lot of those people writing bad code were home-grown programmers who were completely missing pieces of knowledge. From what I saw as an undergrad, it wasn't the 3.75 GPA CS students who were doing those things.

So, seriously, do you have data showing that the bar is lower?

It's not my job to do such studies, however I do interview job applicants. A disturbingly large number of applicants, who all have 3.75+ GPAs, try to tell me nonsense, like "null pointers take up no data." I'd say I encounter something about as egregious as that with a bit short of half. In my recollections of interactions with classmates, I could take it for granted that CS students who made it past Freshman year knew enough to actually implement algorithms and could actually implement a recursive function. If you had tried to talk to them about such things as some kind of deep esoteric knowledge, they would've just given you a funny look.

Re: Optimizing a breadth-first search

#27

Post by stcredzero »

spike021 wrote: post #20
stcredzero wrote: post #15

Something has happened to Comp Sci programs over the past 3 decades. Based on what's too small a sample size (the graduates I've been interviewing in SF) it seems like a very large number of graduates from CS programs with 3.75 GPAs or above, can't do much more than glue together libraries, can't practically design a system on their own, and if ever confronted with a graph theory problem, can't do much more than name…

>Something has happened to Comp Sci programs over the past 3 decades. Based on what's too small a sample size (the graduates I've been interviewing in SF) it seems like a very large number of graduates from CS programs with 3.75 GPAs or above, can't do much more than glue together libraries, can't practically design a system on their own, and if ever confronted with a graph theory problem, can't do much more than nam…

because they didn't necessarily "slog" through stuff, have some troubles, not try to just memorize formulas and algorithms, they don't have the ability to think through problems

http://v.cx/2010/04/feynman-brazil-education

Re: Optimizing a breadth-first search

#28

Post by stcredzero »

ball_of_lint wrote: post #25
stcredzero wrote: post #15

Something has happened to Comp Sci programs over the past 3 decades. Based on what's too small a sample size (the graduates I've been interviewing in SF) it seems like a very large number of graduates from CS programs with 3.75 GPAs or above, can't do much more than glue together libraries, can't practically design a system on their own, and if ever confronted with a graph theory problem, can't do much more than name…

3.75 is a very high bar. I don't pass that bar. At that point I'd expect to be filtering work ethic much more strongly than skill or talent. There may be some grads that have the problems that you describe but there are also many that have those skills. Look at the ICPC regional contests. Many students competing are very highly skilled in algorithms and hacking things together quickly. That does not always make them…

3.75 is a very high bar.

https://www.pbs.org/newshour/economy/column-how-an-epidemic-...

Re: Optimizing a breadth-first search

#29

Post by stcredzero »

Asooka wrote: post #23
hashkb wrote: post #19

Earlier quoted context omitted.

Nobody here would deny the business value of gluing APIs together. We're not asking for your empathy, either; but we are telling you the truth about the difference between where the bar was and where it is now. The idea that "computers are fast, my code just needs to work" is a really really horrible way to treat your users' devices. A whole host of similar ideas are now popular, and it's pretty obvious that it's bec…

Maybe the counterpoint should be that gluing things together should produce better optimised products. You could probably even charge for tools like that. Why should the programmer have to know the best data structures and algorithms if the computer can do it for them? We don't hand-optimise assembly any more either, except in very narrow cases.

Maybe the counterpoint should be that gluing things together should produce better optimised products.

It can, if those doing the gluing have the requisite knowledge.

Re: Optimizing a breadth-first search

#30

Post by agumonkey »

frankmcsherry wrote: post #3

https://en.wikipedia.org/wiki/Iterative_deepening_depth-firs... Edit: for context, wasn't meant to be "zomg how you so dumb" so much as "everyone should also read, cause is relevant".

wow, I've thought about this for so long .. never would have found this wikipedia page on my own.
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