Data structures and algorithms I actually used while working at tech companies

Post by unclewalter » Wed, Jul 15, 2020, 1:04 PM UTC

tchaffee wrote: post #178

GeneralMayhem wrote: post #176

Earlier quoted context omitted.

>Lots of engineer types freeze when they have to make a presentation. I remember a meeting early in my career with literally three people in a conference room and I almost had a panic attack. That's definitely an unfortunate experience, but isn't giving presentations to explain your ideas - sometimes to people you don't really know - actually a significant part of the job? I'm an IC, and I present designs and project…

What is an IC? > isn't giving presentations to explain your ideas - sometimes to people you don't really know - actually a significant part of the job? For many engineering positions it is not. There are loads of shops where the developers, even senior developers, mostly just write code. I have hired many of them and put them to work successfully building stuff while I deal with the meetings. > If I were conducting a…

Post by paulryanrogers » Wed, Jul 15, 2020, 1:07 PM UTC

pps43 wrote: post #179

Taek wrote: post #22

Earlier quoted context omitted.

We always tell our candidates in advance what algorithms we'll be quizzing them on. And it's pretty much always: + fibbonacci + a sort + a linked list I like having candidates write out these problems on paper because it shows that they know how to think about code. Fibbonacci allows us to see that they have basic recursion understanding, and basic iterative loop understanding. Linked lists shows us that they underst…

> Fibbonacci allows us to see that they have basic recursion understanding I see no reason to use recursion when asked to calculate Fibonacci numbers. A loop looks like a more reasonable choice that also avoids typical pitfalls associated with recursion. Maybe that's because I did embedded programming for a while. I suspect recursion is introduced in CS classes with this example, but people understand it as "you are…

Post by ourlordcaffeine » Wed, Jul 15, 2020, 1:10 PM UTC

nostrebored wrote: post #137

eru wrote: post #64

A few years ago I spend lots of time and effort at Goldman Sachs solving a performance problem in a major part of their internal cloud infrastructure. The programme in question was running into performance problems, and a few smart people had already banged their head against a wall solving them. After lots of experiments and different approaches, my solution was to remove most of the advanced data structures that we…

This was the focus of my advanced algorithms course at Georgia Tech in my senior year. We had basically a full semester on random algorithms, and I remember walking out each day feeling like the fancy algorithms I'd memorized the previous year were a bit less glamorous. The number of algorithms that removed multiple complicated stateful steps with 'and we randomly select an element from the array' was mindblowing. As…

Post by watwut » Wed, Jul 15, 2020, 1:16 PM UTC

Taek wrote: post #22

ajuc wrote: post #10

I've used Dijkstra algorithm for calculating distance in a graph once. It was a highlight of that month. Of course I had to look it up(despite learning it and implementing it at university). Who remembers this stuff exactly after years of glueing libraries together? And even if you remember - won't you check it anyway just to be sure? It's OK to ask people general questions (what's algorithmic complexity, what kind o…

We always tell our candidates in advance what algorithms we'll be quizzing them on. And it's pretty much always: + fibbonacci + a sort + a linked list I like having candidates write out these problems on paper because it shows that they know how to think about code. Fibbonacci allows us to see that they have basic recursion understanding, and basic iterative loop understanding. Linked lists shows us that they underst…

Post by watwut » Wed, Jul 15, 2020, 1:18 PM UTC

lootsauce wrote: post #63

Taek wrote: post #22

Earlier quoted context omitted.

We always tell our candidates in advance what algorithms we'll be quizzing them on. And it's pretty much always: + fibbonacci + a sort + a linked list I like having candidates write out these problems on paper because it shows that they know how to think about code. Fibbonacci allows us to see that they have basic recursion understanding, and basic iterative loop understanding. Linked lists shows us that they underst…

This sounds like a reasonable approach and that is why software interviews remain broken. I'm sure it works for your organization, not saying you are bad at hiring or anything but it still smacks of the kind of hoop-jumping that turned me off so much from the process last time I was interviewing. This included on-the-spot coding exercises, massive take-home projects that required many hours of undifferentiated grunt…