I don't like whiteboarding interview, and I recently "failed" one. However, I can see the value in them to the employer.
To pass my whiteboarding interview, I needed first to review data structures and algorithms. It had been a while, so I went back to the textbook and got to the point where I could write mergesort, quicksort, dfs, and bfs, as well as do various permutations of sets (the sort of thing that you draw on when they ask you, for instance, to print all arrangements of a string), and could do this instantly (not by rote, through understanding, but "memorized" in the sense that I didn't have to reason through it, I could just write them on a whiteboard). Once I had that solid, I bought a copy of "Cracking the Coding Interview" and started working through the exercises. My goal wasn't to memorize, but to get to the point where I could answer medium to difficult level questions accurately on paper or whiteboard (no typing, no compiler) in 45 minutes or less.
I was unable to get to that point in the time I had to prepare. I should have asked for more time - I scheduled my interview for 3.5 weeks away, and I did devote a substantial amount of time to study. However, I lack the ability to get up to speed in that amount of time. You really do need to be razor-sharp at the whiteboard, and I just wasn't there. My guess is that I could get there in 3-6 months, studying about 15-20 hours a week. Others may not find this as difficult.
There was also a point in my life when I could probably have done this more easily. I have two kids, I'm married, I have a full time job, and there are a lot of demands on my time. It's far more difficult for me to shake 15-20 hours loose a week than it used to be.
Honestly, I do think that the ability and willingness to prepare for and pass an exam like this probably is a very strong indicator of success in the kind of environment where these developers will be working. In short, the constraints on my life and my own personal limitations that make it difficult for me to pass this exam would probably have reduced my value to an employer. They either need someone with more talent and an ability to get into this sort of form on shorter notice, or someone with more time who is willing to spend it on this sort of thing. I'm not happy about it, but there you go.
My broken record: companies are generally free to do as they please (within the limits of anti-discirmination laws, and so forth), but they should stop talking about a shortage of developers if this is how they wish to hire.
To pass my whiteboarding interview, I needed first to review data structures and algorithms. It had been a while, so I went back to the textbook and got to the point where I could write mergesort, quicksort, dfs, and bfs, as well as do various permutations of sets (the sort of thing that you draw on when they ask you, for instance, to print all arrangements of a string), and could do this instantly (not by rote, through understanding, but "memorized" in the sense that I didn't have to reason through it, I could just write them on a whiteboard). Once I had that solid, I bought a copy of "Cracking the Coding Interview" and started working through the exercises. My goal wasn't to memorize, but to get to the point where I could answer medium to difficult level questions accurately on paper or whiteboard (no typing, no compiler) in 45 minutes or less.
I was unable to get to that point in the time I had to prepare. I should have asked for more time - I scheduled my interview for 3.5 weeks away, and I did devote a substantial amount of time to study. However, I lack the ability to get up to speed in that amount of time. You really do need to be razor-sharp at the whiteboard, and I just wasn't there. My guess is that I could get there in 3-6 months, studying about 15-20 hours a week. Others may not find this as difficult.
There was also a point in my life when I could probably have done this more easily. I have two kids, I'm married, I have a full time job, and there are a lot of demands on my time. It's far more difficult for me to shake 15-20 hours loose a week than it used to be.
Honestly, I do think that the ability and willingness to prepare for and pass an exam like this probably is a very strong indicator of success in the kind of environment where these developers will be working. In short, the constraints on my life and my own personal limitations that make it difficult for me to pass this exam would probably have reduced my value to an employer. They either need someone with more talent and an ability to get into this sort of form on shorter notice, or someone with more time who is willing to spend it on this sort of thing. I'm not happy about it, but there you go.
My broken record: companies are generally free to do as they please (within the limits of anti-discirmination laws, and so forth), but they should stop talking about a shortage of developers if this is how they wish to hire.