AN INTERVIEW QUESTION AT GOOGLE
July 2, 2013 Leave a comment
“What is your strategy to find your car along a very long street if you don’t remember the parking place?”
Being under interview pressure, I quickly improvised an answer like this: I double the distance every time I change direction.
The mathematically correct answer might be the linear search.
To go X blocks (cars) in one direction, then 2X in the other, then 4X forwards, 8X in the reverse direction etc… The initial X depends on the standard deviation.
Now I have time to think about the real problem, I find that the theoretically correct answer is not correct for real life. My mistake was sticking to the initial data; I did not think about the real situation. There are no infinite streets in real life.
One of the practical approaches is : choose a direction and go until the end; if I am not lucky, then go in the other direction.
When I ask a manager about the solution he said: “I will use the key signalization to find my car.” This is “a management solution”.
Is this problem an example of the math paradox: the theoretical solution is not the same as the practical choice? There are many anecdotes about mathematicians: mathematicians are absolutely right and absolutely useless.
Here the list of 140 questions at Google:
Recently, the senior vice president of people operations at Google admits that certain brainteasers are useless.
When I applied to my recent job, there were not formal interviews. We just discussed business development. At a dinner, the company owner asked funny coin puzzles. I was the first who correctly answered. I got the job.
I still think that such challenges are very useful. I do it. Engineering and non-HR managers still informally use such questions.
I did not get the job at Google and I am happy about that. Since that time, I have collected logic problems and put 150+ questions/answers into a book titled Job Interview Logic Puzzles. This is a great help for engineers and managers who want to be ready for challenging interview questions.