4 ms·

We would give interviewees a little sample of code (e.g, a minimal string copy function using a loop in C) and ask how they would make it better, without defini

We would give interviewees a little sample of code (e.g, a minimal string copy function using a loop in C) and ask how they would make it better, without defining what better meant. Some developers would try to optimise it, others would point out the bad variable names and lack of documentation, or talk about unit tests. It was a starting point for a discussion.

jghn 2y ago
Not really. Some places did that sure. And some places do that now. But the cargo cutled nonsense before leetcode were the brain teasers. "How many ping pong balls can fit into a 747?". Also nonsense.
- JTyQZSnP3cQGa8B 2y ago
  It depends where you live and apply. In France I never had whiteboards, leeetcode, or psychological puzzles. It has always been “let’s talk for an hour about this specific language that we use so you can prove you’re a good fit.”
  - jghn 2y ago
    Agree. I'm talking about the US. Much like today where the belief that 100% of the companies do leetcode, 20 years ago the belief was that 100% of the companies did brain teasers. Neither are true. And that was my real point. There was still the annoying cargo culled crap that way too mnay companies used, but back then, just like today, plenty of companies don't do this. And that's your point. EDIT: Don't get me wrong. It's annoying as fuck how many companies interview this way. It's just not as ubiquitous as HN leads on
- jaredsohn 2y ago
  This book was about puzzle interview questions from Microsoft in the early 2000s: https://www.amazon.com/How-Would-Move-Mount-Fuji/dp/0316778494 https://www.amazon.com/How-Would-Move-Mount-Fuji/dp/03167784... Also, a famous question around that time was 'why are manhole covers round?'. (Thought there was a book from that era with that name but not seeing it; only found a newer book.) Remember doing interview prep at the time by trying to memorize the answers to a bunch of these puzzles. Leetcode is useful in comparison to that. I had an interview once where the interviewer could tell I knew these and he was asking me to tell him about others I knew about.
  - jghn 2y ago
    "Remember doing interview prep at the time by trying to memorize the answers to a bunch of these puzzles. " I remember bumping into a friend on the subway, he was coming back from an interview. We were trying to work out some cockamamie puzzle involving barnyard animals crossing the river. He felt he got it right, but one of the interviewers grilled him. When I got home I googled the problem and found out there was a generally accepted answer that was wrong. And that's what the interviewer was pushing. My friend had arrived at the correct answer. And he didn't get the job.
    - ngc248 2y ago
      Ah the crossing the river puzzle, got that during my campus interviews.
  - riffraff 2y ago
    The manhole cover thing was always confusing for me, as where I'm from manholes are all square.
    - jaredsohn 2y ago
      Wonder if people where you're from run into problems where the manhole covers tip onto their diagonal and fall in (since that's the answer I memorized and I think is known as the predominant reason.)
      - riffraff 2y ago
        yeah I also memorized that answer, but my follow up question is: storm drain grates[0] seem to be commonly made in a rectangular form, why doesn't the same issue apply there? [0] https://en.wikipedia.org/wiki/Storm_drain https://en.wikipedia.org/wiki/Storm_drain
      - Ekaros 2y ago
        Isn't actual reason that round shapes handle pressure better. So in the end it is about shape of the hole not the cover. As holes in ground are not square. Then again I think here we have both, square and round. Square ones are more for rain runoff on sides of roads. Where as anything in middle of road are round usually with no grating and some rain water run off locations are also round for access again.
- vertis 2y ago
  But the brain teaser is also just an exercise in trying to get a discussion going. Okay so how could I possibly memorise the volume of a 747 and a ping pong ball, and even if you give me that it's a decent amount of complexity to calculate. But are we accounting for their comfort and making sure they all have TV screens? Do we have to account for FAA regulations? Is it okay if some of the ping pong balls get damaged as we try to fill the aircraft? Are we completely emptying the aircraft or leaving the seats in? Does the plane still have to fly and if so which areas have to be accessible in FAA regulations? What is the weight of a ping pong ball and if you have enough of them does that come close to the allowed take-off weights? Some of how you respond to these is an indication of how you will respond to challenges and frustrations in the team.
  - jghn 2y ago
    This was always the claim, yes. And much like how these days people complain about getting rejected for slipping up on a leetcode problem in a minor way, back then there were plenty of stories of interviewers treating these problems as a black & white problem where you were expected to just know the answer. To be clear, the problem wasn't the question. It was the interviewer asking the question.
- drewcoo 2y ago
  So Fermi problems are considered brain-teasers? We considered those especially useful for PMs. https://en.wikipedia.org/wiki/Fermi_problem https://en.wikipedia.org/wiki/Fermi_problem

jghn 2y ago

Not really. Some places did that sure. And some places do that now. But the cargo cutled nonsense before leetcode were the brain teasers. "How many ping pong balls can fit into a 747?". Also nonsense.

JTyQZSnP3cQGa8B 2y ago
It depends where you live and apply. In France I never had whiteboards, leeetcode, or psychological puzzles. It has always been “let’s talk for an hour about this specific language that we use so you can prove you’re a good fit.”
- jghn 2y ago
  Agree. I'm talking about the US. Much like today where the belief that 100% of the companies do leetcode, 20 years ago the belief was that 100% of the companies did brain teasers. Neither are true. And that was my real point. There was still the annoying cargo culled crap that way too mnay companies used, but back then, just like today, plenty of companies don't do this. And that's your point. EDIT: Don't get me wrong. It's annoying as fuck how many companies interview this way. It's just not as ubiquitous as HN leads on
jaredsohn 2y ago
This book was about puzzle interview questions from Microsoft in the early 2000s: https://www.amazon.com/How-Would-Move-Mount-Fuji/dp/0316778494 https://www.amazon.com/How-Would-Move-Mount-Fuji/dp/03167784... Also, a famous question around that time was 'why are manhole covers round?'. (Thought there was a book from that era with that name but not seeing it; only found a newer book.) Remember doing interview prep at the time by trying to memorize the answers to a bunch of these puzzles. Leetcode is useful in comparison to that. I had an interview once where the interviewer could tell I knew these and he was asking me to tell him about others I knew about.
- jghn 2y ago
  "Remember doing interview prep at the time by trying to memorize the answers to a bunch of these puzzles. " I remember bumping into a friend on the subway, he was coming back from an interview. We were trying to work out some cockamamie puzzle involving barnyard animals crossing the river. He felt he got it right, but one of the interviewers grilled him. When I got home I googled the problem and found out there was a generally accepted answer that was wrong. And that's what the interviewer was pushing. My friend had arrived at the correct answer. And he didn't get the job.
  - ngc248 2y ago
    Ah the crossing the river puzzle, got that during my campus interviews.
- riffraff 2y ago
  The manhole cover thing was always confusing for me, as where I'm from manholes are all square.
  - jaredsohn 2y ago
    Wonder if people where you're from run into problems where the manhole covers tip onto their diagonal and fall in (since that's the answer I memorized and I think is known as the predominant reason.)
    - riffraff 2y ago
      yeah I also memorized that answer, but my follow up question is: storm drain grates[0] seem to be commonly made in a rectangular form, why doesn't the same issue apply there? [0] https://en.wikipedia.org/wiki/Storm_drain https://en.wikipedia.org/wiki/Storm_drain
    - Ekaros 2y ago
      Isn't actual reason that round shapes handle pressure better. So in the end it is about shape of the hole not the cover. As holes in ground are not square. Then again I think here we have both, square and round. Square ones are more for rain runoff on sides of roads. Where as anything in middle of road are round usually with no grating and some rain water run off locations are also round for access again.
vertis 2y ago
But the brain teaser is also just an exercise in trying to get a discussion going. Okay so how could I possibly memorise the volume of a 747 and a ping pong ball, and even if you give me that it's a decent amount of complexity to calculate. But are we accounting for their comfort and making sure they all have TV screens? Do we have to account for FAA regulations? Is it okay if some of the ping pong balls get damaged as we try to fill the aircraft? Are we completely emptying the aircraft or leaving the seats in? Does the plane still have to fly and if so which areas have to be accessible in FAA regulations? What is the weight of a ping pong ball and if you have enough of them does that come close to the allowed take-off weights? Some of how you respond to these is an indication of how you will respond to challenges and frustrations in the team.
- jghn 2y ago
  This was always the claim, yes. And much like how these days people complain about getting rejected for slipping up on a leetcode problem in a minor way, back then there were plenty of stories of interviewers treating these problems as a black & white problem where you were expected to just know the answer. To be clear, the problem wasn't the question. It was the interviewer asking the question.
drewcoo 2y ago
So Fermi problems are considered brain-teasers? We considered those especially useful for PMs. https://en.wikipedia.org/wiki/Fermi_problem https://en.wikipedia.org/wiki/Fermi_problem