Comment by sparknlaunch12 | Hacker News Reader

Comment by sparknlaunch12 | Hacker News Reader

Great overview of the different interview styles being used. I cannot say I am convinced you always get the best people through.

I don't have any aspirations to interview at Google, but did stumble across an 'Google Interview' book at the local bookstore. It makes great reading.

WSJ did an article on Google interviews late last year, including answers. Here are the questions (click the link below if you want answers).

"1. What's the next number in this sequence: 10, 9, 60, 90, 70, 66 … ?

2. You're in a car with a helium balloon on a string that is tied to the floor. The windows are closed. When you step on the gas pedal, what happens to the balloon—does it move forward, move backward, or stay put?

3. Using only a four-minute hourglass and a seven-minute hourglass, measure exactly nine minutes—without the process taking longer than nine minutes.

4. A book has N pages, numbered the usual way, from 1 to N. The total number of digits in the page numbers is 1,095. How many pages does the book have?

5. A man pushed his car to a hotel and lost his fortune. What happened?"

[Answers] http://online.wsj.com/article/SB1000142405297020455230457711...

FWIW, these questions have no relation to any questions that are asked in engineering interviews at Google. We mostly focus on software design, implementation, and algorithms. (SREs get some UNIX/networking questions, SETs get refactoring questions, and so on. And some interviewers like math questions.)

As someone who interviews prospective Google engineers, I can confirm what others are saying: The WSJ is full of shit. None of those questions would ever be asked here.

Especially that ridiculous, idiotic Monopoly one that journalists seem to love.

This is bullshit. None of these could be a real google interview question.

The explanation given in wsj for problem 2 is totally wrong. The balloon will do the same as a person in the car (nod backwards), only less pronounced due to air resistance.

Actually, the WSJ is correct. Helium has a lower density than air, while a head has a higher density. Hence, they will move in opposite directions.

Have you tried it? I have. It's quite startling the first time you put a bunch of helium balloons in your car, accelerate away from a stoplight, and have them all crowd up against the windshield.

In an accelerating car, the air sloshes toward the back, producing a pressure gradient. The helium balloons, being ligher than air, will be crowded out by the sloshing air and will drift toward the area of lowest density, which is in the front.

I can assure you that the wsj is correct! I've been transporting balloons a bit lately* and having fun watching them 'lean in' to turns, 'leaning back' while braking, and 'leaning forward' while accelerating.

*transporting balloons correlates strongly with transporting kids

Good grief, I stand corrected.

Brain teasers of this kind were banned at Google circa 2006.

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