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Trees and graphs are fundamental to computer science and there are only two ways to traverse them. I don't know what kids are doing these days, but I learned th

Trees and graphs are fundamental to computer science and there are only two ways to traverse them. I don't know what kids are doing these days, but I learned this because of my high-school curricula. In other words, it's OK if you don't have a formal education in computer science, but when you don't have it, you need to make up for it by learning on your own, because this is basic stuff that high-school kids are learning. And it's even worse when people do have that education on their resume and don't know BFS, because it means they cheated on those courses. And what would you prefer for a hiring test? Straight IQ tests? A requirement for public, open-source contributions? Or are you speaking of querying databases and fading out divs? I think we can all agree that neither is entirely fair. And keep in mind that for all the pain involved in the interview process, the only alternative is optimistic hiring for a test period, except that doesn't work because it causes distress to everybody involved if it doesn't work out. This is why many companies now prefer internships, because thus they are dealing with young people that don't have big expectations.

ts330 11y ago
You're right about learning. Everyone should be doing this ALL THE TIME. Problem solving and learning ability are what you should be measuring and then deciding if their past experience justifies the position/starting rate. This is far more likely to serve you well than testing the finer points of some algo/tech that is simply a building block of a solution to a far bigger set of business/technical challenges.
- bad_user 11y ago
  But you cannot measure problem solving and learning ability without relying on a set of common knowledge to use in your tests. Again, are we speaking of giving out straight IQ tests? I think there's plenty of people that would be against that, plenty of people that consider IQ tests to be fundamentally flawed. And if not IQ tests, how do you measure problem solving and learning ability? Maybe you give the interviewee something to do, like an algorithm or a piece of code to develop on the spot, right? But maybe your personal expertise doesn't match with what the interviewer wants or needs. And the interviewer has to give you some problem to solve in some way. I remember that at a coding interview I was given the problem of programming a Lego Mindstorms device to detect obstacles and do stuff. But then the problem was really about reading a document on the C subset used to program the device, along with the several couple of functions needed to control the motion and read the sensors. Was that measuring learning ability in any way? Of course, if you think that the skill of reading a technical document with precise instructions is so rare. But that wasn't real world problem solving. So how can you test real world problem solving? Do you give candidates a homework? Ah, but then you run into another problem: the good candidates, the ones that might actually solve your homework, are rarely interested in spending their time on such things, because most good people already have jobs and a life and things to do and you can consider yourself lucky if you get their attention for a couple of hours. In that light, I don't think it's that unfair to give problems to solve that rely on basic algorithms and data structures, especially for companies where the problems solved are much harder than that.
stegosaurus 11y ago
I think this makes sense if you consider an interview as extending a hand to a poor, down-trodden vagrant, rather than an exchange amongst equals. The article might go over the top a bit with self-pity, but personally I just see it as suboptimal behaviour. http://danluu.com/programmer-moneyball/ http://danluu.com/programmer-moneyball/ - Dan Luu explains better than I can. I think fundamentally the idea of paying developer X 40K and developer Y 80K (because developer Y has been twice as effective in the past) is broken, because it negates the impact of environment. If you pay someone 150K GBP in London they can live next door to the office, have TaskRabbit like services perform all household tasks for them, and spend their time exercising and reading 24/7. They will kill it. Pay them 30K, and regardless of pedigree, they're going to struggle. Somewhere in there is a balance and I argue it's far less to do with certification and more the circumstances of life which as an employer you have huge discretion to influence. Basically, it's about steelmanning. Why is someone bad? Is it that they're inherently genetically dysfunctional? Or is it that they haven't been coached well or have a difficult environment? Given good faith, most of the developers I know have the ability to be amazing. I include myself in that (am I that good? dunno, impostor syndrome innit). But they are stifled by needless nonsense. Management, open office, low pay, commute, stress, basically. Kill the stress and you get your '10x engineer'. Keep the stress and your '10x engineer' turns into a chocolate mousse.
- bad_user 11y ago
  Are you sure you replied to the right comment? :-) From my point of view, an interview really isn't an exchange between equals, but a meetup where two parties meet, state their demands and evaluate each other. It works in both directions of course.
  - stegosaurus 11y ago
    Yes, I am. >> From my point of view, an interview really isn't an exchange between equals If you design it that way, sure. It doesn't have to be like that. The whole principle here is that there exists a growing portion of developers who can't be bothered with interview ping pong. If you don't want them, great! Everyone wins. You don't need to convince us, we won't be working at your company anyway.
dimino 11y ago
I'v;e been programming for 8 years and have never ran into a BFS problem. Why do I need to know this to be an effective programmer again?
- Morgawr 11y ago
  I've been programming for ~8 years as well and have implemented BFS multiple times, especially in occasions where I have to travel nested data structures and want to print them in a specific order. BFS and DFS are the bread and butter of tree/graph problems and every software engineer is expected to encounter them at least once in their life. What if you want to debug a complex data structure or just a tree and want to print out its contents in order? Is it really such a weird thing? It's akin to asking to do a for loop through a list to print the elements, except slightly more complex (but certainly something that should be achievable by intuition rather than by memory).
  - dimino 11y ago
    I guess I should rephrase. I've been programming for ~8 years and I've never been presented with a problem that insisted I know what BFS was explicitly. It is intuitive, which even further pushes the question "Why do I need to know this to be an effective programmer"?
    - Morgawr 11y ago
      You don't need to know BFS, you need to show that you can come up with a BFS implementation if you need to do so. You can always say "wait, remind me again, which one was BFS?" and the interviewer can certainly tell you at least what the conditions are. Maybe he might think a bit less of you (although I personally wouldn't) because BFS is a really really common name in the jargon of a programmer, but still it's better than simply blanking out and then angrily claiming that it's unfair to ask BFS. A similar question could be "Can you print in order all the elements of a given tree/graph?", would you find that more fair compared to straight out using the word "BFS/Breadth First Search"?

ts330 11y ago

You're right about learning. Everyone should be doing this ALL THE TIME. Problem solving and learning ability are what you should be measuring and then deciding if their past experience justifies the position/starting rate. This is far more likely to serve you well than testing the finer points of some algo/tech that is simply a building block of a solution to a far bigger set of business/technical challenges.

bad_user 11y ago
But you cannot measure problem solving and learning ability without relying on a set of common knowledge to use in your tests. Again, are we speaking of giving out straight IQ tests? I think there's plenty of people that would be against that, plenty of people that consider IQ tests to be fundamentally flawed. And if not IQ tests, how do you measure problem solving and learning ability? Maybe you give the interviewee something to do, like an algorithm or a piece of code to develop on the spot, right? But maybe your personal expertise doesn't match with what the interviewer wants or needs. And the interviewer has to give you some problem to solve in some way. I remember that at a coding interview I was given the problem of programming a Lego Mindstorms device to detect obstacles and do stuff. But then the problem was really about reading a document on the C subset used to program the device, along with the several couple of functions needed to control the motion and read the sensors. Was that measuring learning ability in any way? Of course, if you think that the skill of reading a technical document with precise instructions is so rare. But that wasn't real world problem solving. So how can you test real world problem solving? Do you give candidates a homework? Ah, but then you run into another problem: the good candidates, the ones that might actually solve your homework, are rarely interested in spending their time on such things, because most good people already have jobs and a life and things to do and you can consider yourself lucky if you get their attention for a couple of hours. In that light, I don't think it's that unfair to give problems to solve that rely on basic algorithms and data structures, especially for companies where the problems solved are much harder than that.

stegosaurus 11y ago

I think this makes sense if you consider an interview as extending a hand to a poor, down-trodden vagrant, rather than an exchange amongst equals. The article might go over the top a bit with self-pity, but personally I just see it as suboptimal behaviour. http://danluu.com/programmer-moneyball/ http://danluu.com/programmer-moneyball/ - Dan Luu explains better than I can. I think fundamentally the idea of paying developer X 40K and developer Y 80K (because developer Y has been twice as effective in the past) is broken, because it negates the impact of environment. If you pay someone 150K GBP in London they can live next door to the office, have TaskRabbit like services perform all household tasks for them, and spend their time exercising and reading 24/7. They will kill it. Pay them 30K, and regardless of pedigree, they're going to struggle. Somewhere in there is a balance and I argue it's far less to do with certification and more the circumstances of life which as an employer you have huge discretion to influence. Basically, it's about steelmanning. Why is someone bad? Is it that they're inherently genetically dysfunctional? Or is it that they haven't been coached well or have a difficult environment? Given good faith, most of the developers I know have the ability to be amazing. I include myself in that (am I that good? dunno, impostor syndrome innit). But they are stifled by needless nonsense. Management, open office, low pay, commute, stress, basically. Kill the stress and you get your '10x engineer'. Keep the stress and your '10x engineer' turns into a chocolate mousse.

bad_user 11y ago
Are you sure you replied to the right comment? :-) From my point of view, an interview really isn't an exchange between equals, but a meetup where two parties meet, state their demands and evaluate each other. It works in both directions of course.
- stegosaurus 11y ago
  Yes, I am. >> From my point of view, an interview really isn't an exchange between equals If you design it that way, sure. It doesn't have to be like that. The whole principle here is that there exists a growing portion of developers who can't be bothered with interview ping pong. If you don't want them, great! Everyone wins. You don't need to convince us, we won't be working at your company anyway.

dimino 11y ago

I'v;e been programming for 8 years and have never ran into a BFS problem. Why do I need to know this to be an effective programmer again?

Morgawr 11y ago
I've been programming for ~8 years as well and have implemented BFS multiple times, especially in occasions where I have to travel nested data structures and want to print them in a specific order. BFS and DFS are the bread and butter of tree/graph problems and every software engineer is expected to encounter them at least once in their life. What if you want to debug a complex data structure or just a tree and want to print out its contents in order? Is it really such a weird thing? It's akin to asking to do a for loop through a list to print the elements, except slightly more complex (but certainly something that should be achievable by intuition rather than by memory).
- dimino 11y ago
  I guess I should rephrase. I've been programming for ~8 years and I've never been presented with a problem that insisted I know what BFS was explicitly. It is intuitive, which even further pushes the question "Why do I need to know this to be an effective programmer"?
  - Morgawr 11y ago
    You don't need to know BFS, you need to show that you can come up with a BFS implementation if you need to do so. You can always say "wait, remind me again, which one was BFS?" and the interviewer can certainly tell you at least what the conditions are. Maybe he might think a bit less of you (although I personally wouldn't) because BFS is a really really common name in the jargon of a programmer, but still it's better than simply blanking out and then angrily claiming that it's unfair to ask BFS. A similar question could be "Can you print in order all the elements of a given tree/graph?", would you find that more fair compared to straight out using the word "BFS/Breadth First Search"?