Comment On Classic WTF: Job Interview 2.0: Now With Riddles!

This generated almost 900 comments last time. I can hardly wait.

Since all the articles are obfuscated, when it is written Microsoft, it must mean something like Apple or such.

By the way, I like the stationary bike idea ^^

I used to have a boss who liked to ask the following two questions during programmer interviews:
1. Describe to me how your toilet works.
2. Estimate how many ping-pong balls will fit in a 10' x 10' x 10' room; show your work.

His explanation: for #1, he wants programmers that are curious as to how things work and are capable or explaining how things work. If someone never took the time to wonder how their toilet works, or cannot explain clearly how their toilet works, he doesn't want them. For #2, he wanted to know what assumptions were made about the problem, and whether the estimate including any rounding. [The best answer for #2 is "1, if the ping-pong ball is large enough.]

The light bulbs thingy is easy:

First light 1 switch for 5 minutse, so it gets warm.
Turn it off
Turn on the other one and open the box.
First switch corresponsd to warm lightbulb.
Second switch is the lit bulb.
Third switch is the unlit bulb.

I had the opportunity of interviewing at a place that asked these sorts of questions. In my case, the question was one I hadn't heard before, and I just didn't see the answer. I thought for a minute, then told the interviewer that it was irrelevant, impertinent, in no way divulged anything about my abilities as an architect/developer, that I didn't want to work for/with/around/near anyone who believed otherwise, laughed in his face, and walked out.

Sad? Maybe. Necessary? Absolutely. Would I do it again? In a heartbeat! Fools deserve the abuse because they bring it on themselves.

Separately, on another interview a while back, the guy asked me to write a program to display the numbers from 1-100 in a printed matrix, along with some other info. Then he lets me at his computer to write the program. And leaves the room while I do it (don't get me started on this one). No biggie. He gave me an hour. I finished in 5 minutes. I even put a nice little header on it to indicate what each column meant. The guy runs the program and pipes the output directly through wc -l and tells me it's wrong because the line count is wrong. I tell him to just run it without piping it. He sees the header and says "But I didn't tell you to print out a header". At that point, I tell him I'm not interested in working for someone who so myopically micromanages, and walk out.

Mog:

Yanman.be:

The light bulbs thingy is easy:

First light 1 switch for 5 minutse, so it gets warm.
Turn it off
Turn on the other one and open the box.
First switch corresponsd to warm lightbulb.
Second switch is the lit bulb.
Third switch is the unlit bulb.

But now one of the bulbs is broken. What would you do?

Heeeeeerrrrrrre we go again....

You pull out your trusty sidearm and shoot the other person, then open the box and throw all the switches, one at a time, to see which is which, and close the box. When the replacement person comes along, you provide the answer.

I was flown to Redmond and interviewed for a day at MS back in 1990.

After the fourth such asinine question from the fourth interviewer of the day my patience was completely exhausted. I told him I wasn't answering that kind of question and could he please get on with the real interview.

Obviously didn't get the job :-)

Many years ago I had friends who worked at MS and wanted me to get an interview there. They gave me a sample of the their 'current' interview questions.

The question was the classic 'Why are manhole covers round'. My answer was that 'you get more bang for the buck'. In other words, you get more area for less perimeter when you use a circle. A mathematically correct answer (which, coming from a mathematician, isn't that weird). I was told I was wrong and what the correct answer was.

My response to that was 'I gave a valid answer yet I'm wrong? Please don't get me an interview there.' The classic 'we want you to think outside the box' where outside has been redefined as inside.

snoofle:

I had the opportunity of interviewing at a place that asked these sorts of questions. In my case, the question was one I hadn't heard before, and I just didn't see the answer. I thought for a minute, then told the interviewer that it was irrelevant, impertinent, in no way divulged anything about my abilities as an architect/developer, that I didn't want to work for/with/around/near anyone who believed otherwise, laughed in his face, and walked out.

Sad? Maybe. Necessary? Absolutely. Would I do it again? In a heartbeat! Fools deserve the abuse because they bring it on themselves.

Separately, on another interview a while back, the guy asked me to write a program to display the numbers from 1-100 in a printed matrix, along with some other info. Then he lets me at his computer to write the program. And leaves the room while I do it (don't get me started on this one). No biggie. He gave me an hour. I finished in 5 minutes. I even put a nice little header on it to indicate what each column meant. The guy runs the program and pipes the output directly through wc -l and tells me it's wrong because the line count is wrong. I tell him to just run it without piping it. He sees the header and says "But I didn't tell you to print out a header". At that point, I tell him I'm not interested in working for someone who so myopically micromanages, and walk out.

Wow! Kind of a douche bag aren't you? Guess the interview question did their job.

Guess the interview question did their job.

Guess the interview question did its job.

1/ Boeing : Laden or unladen? Max takeoff or max landing? Or empty?

2/ Opaque box : ask Superman, or failing that, Ask Slashdot

3/ Charter a helicopter

LM:

I was told I was wrong and what the correct answer was.

Which is?.....

Johhny Awkward:

LM:

I was told I was wrong and what the correct answer was.

Which is?.....

Because round looks nicer, and it's friendlier to small animals.

Or because you can't drop a round cover down a round hole, but you can drop [any other shape] covers down [any other shape] holes. And you can ROLL circular covers if you need to move them, and you don't have to orient them in a particular way to get them back on the hole, and all that.

But in fact, square manhole covers DO exist. So it's all bullshit really.

snoofle:

I had the opportunity of interviewing at a place that asked these sorts of questions. In my case, the question was one I hadn't heard before, and I just didn't see the answer. I thought for a minute, then told the interviewer that it was irrelevant, impertinent, in no way divulged anything about my abilities as an architect/developer, that I didn't want to work for/with/around/near anyone who believed otherwise, laughed in his face, and walked out.

Be prepared to be called a humorless dweeb who is no fun to work with. . .

One of the things I look for in a candidate is intellectual curiosity. You should know more languages than the ones you use all the time. You should know about the existence of many of the things out there.

For instance, even if you have never done anything involving transactions, you should know something about the concept. If you're used to writing single-user single-machine applications and you are designing your first multi-user Web application with a database, you should know that there's an established way of handling multi-user access to a database.

I interviewed a candidate for a position that required XML expertise. He knew XML, but had never seen entities (& ' and so on). Maybe you can do some XML work without knowing about entities, but I don't want someone with an extremely narrow horizon.

A better question than "how would you estimate the weight of a Boeing 747" is "We want to build a commerce site that will become as large as Amazon.com. How many server should we buy for it?" Stated that way it still looks like a ridiculous sort of question. You might restate it as: "We want to build a commerce site that will be as large as Amazon.com. Is it technically feasible? What would the large-scale architecture look like?"

Manhole covers are round because manholes are round. Duh. :)

LM:

The question was the classic 'Why are manhole covers round'. My answer was that 'you get more bang for the buck'. In other words, you get more area for less perimeter when you use a circle. A mathematically correct answer (which, coming from a mathematician, isn't that weird). I was told I was wrong and what the correct answer was.

My response to that was 'I gave a valid answer yet I'm wrong? Please don't get me an interview there.' The classic 'we want you to think outside the box' where outside has been redefined as inside.

You gave a wrong answer.

The answer is that a round manhole cover won't fall back into the hole since, with the lip, it is always wider than the manhole no matter how you turn it.

Anon:

snoofle:

I had the opportunity of interviewing at a place that asked these sorts of questions. . . .

Wow! Kind of a douche bag aren't you? Guess the interview question did their job.

Told you.

fruey:

1/ Boeing : Laden or unladen? Max takeoff or max landing? Or empty?

African or European?

B92:

The biggest disservice that I could perform in an interview is ask "What are your biggest strenths and what is your biggest weakness?" Completely useless.

I read an amusing answer to "What's your biggest weakness?" once: "I tend to lose patience with people who aren't as ___________ as I am."

Fill in the blank with your choice of "dedicated", "productive", "visionary", etc.

Some dude:

Manhole covers are round because manholes are round.

And manholes are round because the pipes are.

Cue discussion about different shapes of manholes including but not limited to Reuleaux triangles.

snoofle:

Mog:

Yanman.be:

The light bulbs thingy is easy:

First light 1 switch for 5 minutse, so it gets warm.
Turn it off
Turn on the other one and open the box.
First switch corresponsd to warm lightbulb.
Second switch is the lit bulb.
Third switch is the unlit bulb.

But now one of the bulbs is broken. What would you do?

Heeeeeerrrrrrre we go again....

You pull out your trusty sidearm and shoot the other person, then open the box and throw all the switches, one at a time, to see which is which, and close the box. When the replacement person comes along, you provide the answer.

But, what if you lived in a world with no Zinc, so there was no firing pin in the gun?

That bike question may have gotten some overengineering guy the job. But at least it flushed out the a$$hole in the process.

I was interviewed back in 2001 at Microsoft at Redmond Campus for 5 hours by 5 different people, one hour each. Apparently people where flew in from around the country for this position and there were over 75 applicants.

It all went well for the first couple hours; first hour was a database admin, second hour was an application architect, third hour was a development lead. I can't remember the exact wording but I found a very similar one on the internet that I am reposting:

"A man from New York lived in a ten-story apartment building. Every sunny day his routine would be as follows: He took the elevator all the way down to the lobby, drove to work, came home, then took the elevator back up to the seventh floor, and walked up the rest of the three flights to his apartment building. Other days, when it rained, he came home from work and rode the elevator all the way to his apartment on the tenth floor. Why the change in his routine?"

I managed to come up with the answer stating that it must be a very short man who could not reach the button normally without his umbrella.

The other two interviewers - the project manager and QA person managed to produce normal and relevant questions.

I was offered the job.

I turned it down. Through the interview I found it was a horrible death march project that no sane person would take - the development person left, it was 4 months behind, there were 6 months of work left and it was due in 5 months.

snoofle:

Mog:

Yanman.be:

The light bulbs thingy is easy:

First light 1 switch for 5 minutse, so it gets warm.
Turn it off
Turn on the other one and open the box.
First switch corresponsd to warm lightbulb.
Second switch is the lit bulb.
Third switch is the unlit bulb.

But now one of the bulbs is broken. What would you do?

Heeeeeerrrrrrre we go again....

You pull out your trusty sidearm and shoot the other person, then open the box and throw all the switches, one at a time, to see which is which, and close the box. When the replacement person comes along, you provide the answer.

Taking apart and reverse engineering the box is the obvious solution. The real test is whether or not they remember to pull power. If they don't, they're not as safe of an engineer.

fruey:

1/ Boeing : Laden or unladen? Max takeoff or max landing? Or empty?

Zero Fuel Weight? Taxi (Ramp) weight? With or without fluids?

Or the most obvious:

What's the serial number of said 747? (each one weighs differently due to many variables (amount of paint applied, amount of metal, etc). Each 747 that rolls out from Boeing weighs differently.

Worf:

fruey:

1/ Boeing : Laden or unladen? Max takeoff or max landing? Or empty?

Zero Fuel Weight? Taxi (Ramp) weight? With or without fluids?

Or the most obvious:

What's the serial number of said 747? (each one weighs differently due to many variables (amount of paint applied, amount of metal, etc). Each 747 that rolls out from Boeing weighs differently.

The serial number only matters if you're planning to call Boeing and ask them the weight. If you need to estimate the weight of an actual 747 as it's sitting outside on the tarmac, the serial number doesn't matter.

fruey:

1/ Boeing : Laden or unladen?

Bin Laden

This was my thought exactly - last time we got a twenty-page epic arguing about the best way to solve the "red hats and blue hats" problem (which I'm not repeating) and whether there's always an equal chance of a coin landing on heads or tails. It was painful - don't do this to us again!

There are no manhole covers. There are only subterranean access hole covers. So don't ask me about the shape of something that doesn't exist anymore.

I was asked once to tell an estimate of the number of people that are born every minute on Earth. (Under stress, as it was the 7th interview in a couple of days for that particular job, I gave the wrong answer.)
The job consisted in maintaining a financial system written in an old programing language and eventually porting that system to Java.
Very relevant.

eric76:

The answer is that a round manhole cover won't fall back into the hole since, with the lip, it is always wider than the manhole no matter how you turn it.

And you can't have a lip on any other shape?

Manhole covers are round because the manholes are round, and the manholes are round because drills create round holes. Duh.

THAT is the best answer by far. It implies you think out of the box. It implies you know what questions you should ask a client when getting the requirements and it implies we could spend hours talking about Monty Python's movies and Flying Circus.

snoofle:

Mog:

Yanman.be:

The light bulbs thingy is easy:

First light 1 switch for 5 minutse, so it gets warm.
Turn it off
Turn on the other one and open the box.
First switch corresponsd to warm lightbulb.
Second switch is the lit bulb.
Third switch is the unlit bulb.

But now one of the bulbs is broken. What would you do?

Heeeeeerrrrrrre we go again....

You pull out your trusty sidearm and shoot the other person, then open the box and throw all the switches, one at a time, to see which is which, and close the box. When the replacement person comes along, you provide the answer.

You notice you forgot to reload after you killed the last idiot to make you a stupid interview question, and you have no bullets around. To top it off, the chair, desk and the box are bolted to the ground so you can't use them as weapons (probably someone had the same reaction before). Now what do you do?

ThomsonsPier:

fruey:

1/ Boeing : Laden or unladen? Max takeoff or max landing? Or empty?

African or European?

THAT is the best answer by far. It implies you think out of the box. It implies you know what questions you should ask a client when getting the requirements and it implies we could spend hours talking about Monty Python's movies and Flying Circus.

akatherder:

How would you determine the weight of a Boeing 747?

With a scale.

Where are you going to find a scale that big!?

Your mom's bathroom.

Best answer ever

eric76:

LM:

The question was the classic 'Why are manhole covers round'. My answer was that 'you get more bang for the buck'. In other words, you get more area for less perimeter when you use a circle. A mathematically correct answer (which, coming from a mathematician, isn't that weird). I was told I was wrong and what the correct answer was.

My response to that was 'I gave a valid answer yet I'm wrong? Please don't get me an interview there.' The classic 'we want you to think outside the box' where outside has been redefined as inside.

You gave a wrong answer.

The answer is that a round manhole cover won't fall back into the hole since, with the lip, it is always wider than the manhole no matter how you turn it.

You are all insane! Manhole covers are round because they don't have any corners!

The most efficient shape for a manhole cover would be cone-shaped. That way, no matter the size of the hole, the cover would always fit.

What about the extra protrusion when covering rather small manholes, you ask? Wouldn't that hit the bottom of passing cars?

Well, that sounds more like a user problem, not an engineer problem.

What's equally annoying as the riddles is the "na-ah, you can't do that" response to ANY answer you ever give.

Interviewer: "If you had a snorkel, an icepick and an avocado, how would you make a pipe?"

Interviewee: "Well, I'd use the icepick to cut a hole in..."

Interviewer: "No, that's not allowed"

Interviewee: "Well, then I'd bend the snorkel to..."

Interviewer: "Nope, can't do that."

Interviewee: "I'd put the avocado on my cheeseburg.."

Interviewer: "What if the grocery store is closed?"

etc etc etc

Well smartass, you do the exact same thing.

*Broken, warm, never on.
*Lit, broken, never on.
*Lit, cold, broken.

uptaphunk:

I was interviewed back in 2001 at Microsoft at Redmond Campus.

....

I turned it down. Through the interview I found it was a horrible death march project that no sane person would take - the development person left, it was 4 months behind, there were 6 months of work left and it was due in 5 months.

They wanted you to work on Vista?

I always include riddles in my interviews. The point is not to find someone who can solve riddles, the point is to find someone who can think through problems, explain what they're thinking, and ask for help when they need it. I'm looking for someone who will think about the question for awhile, explain what they're stumped on, respond well to hints, and eventually understand how to get to the answer. People who fail are those that don't try at all, refuse to explain their thought process, or give up.

But now one of the bulbs is broken. What would you do?


Put the interviewer's hand to the empty sockets. Note which one delivers a 110V shock. That corresponds to the one that is currently on.

If the interviewer points out that the remaining two switches have yet to be differentiated from one another, repeat step one. He'll eventually overlook this minor detail.

As for the bicycle for the blind - give him a tandem bike, and put a guy who can see in the front.

Anon:

snoofle:

I had the opportunity of interviewing at a place that asked these sorts of questions. In my case, the question was one I hadn't heard before, and I just didn't see the answer. I thought for a minute, then told the interviewer that it was irrelevant, impertinent, in no way divulged anything about my abilities as an architect/developer, that I didn't want to work for/with/around/near anyone who believed otherwise, laughed in his face, and walked out.

Sad? Maybe. Necessary? Absolutely. Would I do it again? In a heartbeat! Fools deserve the abuse because they bring it on themselves.

Separately, on another interview a while back, the guy asked me to write a program to display the numbers from 1-100 in a printed matrix, along with some other info. Then he lets me at his computer to write the program. And leaves the room while I do it (don't get me started on this one). No biggie. He gave me an hour. I finished in 5 minutes. I even put a nice little header on it to indicate what each column meant. The guy runs the program and pipes the output directly through wc -l and tells me it's wrong because the line count is wrong. I tell him to just run it without piping it. He sees the header and says "But I didn't tell you to print out a header". At that point, I tell him I'm not interested in working for someone who so myopically micromanages, and walk out.

Wow! Kind of a douche bag aren't you? Guess the interview question did their job.

I agree... You didn't code to the specs you were given.

Where I live, there is more square manhole covers than there is round ones. So this question never made any sense to me.

Forget riddles, true story from my company's coding quiz:

Imagine possible responses to the software-related question "Define 'atomic operation'."