Watch These Movies if you Want to Work at Google

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Do you remember being taught math when you were young? If you were anything like me you hated word problems. That was the only time during math class that we could not just use mechanical processes. Instead, we had to think about how to apply those processes to real world problems.

The natural evolution of word problems in the adult world is Brain Teasers, those pesky puzzles that are supposed to be fun but, more often, are frustrating. For most people, the skill of solving riddles and impossible estimation problems has never had much use. That was until clever software companies, such as Microsoft and Google, famously began asking these types of questions during job interviews. The legends of these companies’ interview tactics are so predominant that they have essentially become their own category of technical interview questions.

How many golf balls can fit in a school bus?

Unprepared candidates confront brain teasers with shock and horror. A feeling of futility drapes over them like a giant rain cloud. Fortunately, all the candidate needs to understand is that he or she does not necessarily have to answer the puzzle correctly to “pass” the test.

 

The Interviewer’s Perspective

Brain Teasers are great because when they work, they are a simple way to lighten the tone of an interview. They are also great at unearthing important traits of the interview candidate:

• How does the candidate handle pressure, such as a seemingly impossible problem?
• How well can the candidate express his or her thoughts regarding a difficult solution?
• Is the candidate capable of “thinking outside the box” or are all proposed solutions too straight-forward?
• Specific types of puzzles test the candidate’s ability to estimate large unknown quantities.

“A hunter sets up camp, walks 10 miles south and 10 miles east. He shoots a bear and drags it 10 miles north back to his camp. What color is the bear?”

 

My Perspective

Through years of practice, I became comfortable with the word problems in math class. It was a required step in progressing in mathematics. Likewise, Brain Teasers become conquerable with practice.

Personally, I love Brain Teasers now. I enjoy when a friend sends me one I have not before heard. I find it worthwhile to stretch my mind by thinking about different types of problems.

Still, Brain Teasers are rather overused in interviews. As stated above, they can be useful when they work but, when they do not work, they often fluster an otherwise good candidate. Some puzzles require a certain basis of knowledge that can lend itself to bias. Consider the puzzle about the hunter above, the answer is “White.” Why? Because the only place on Earth that someone can walk X distance South, X distance East or West, X distance North and then arrive at the same point again is at the North Pole. Polar bears are the only type of bears that live there. Polar bears are white. The candidate may be able to logically reason through the problem, but sometimes a small piece of “common knowledge” becomes a roadblock.

Lastly, Brain Teasers take too much precious time during an interview to not uncover anything of import. They test the “A-Ha moment” of the candidate, a long period of silence followed by the sudden discovery of the answer in the candidate’s mind. In cases where the candidate solves the problem right away, it usually does not mean that the candidate is brilliant but that he or she has heard it before.

 

Tips for the Interviewee

As I mentioned, it is not required of the candidate to solve the problem. In most cases, the interviewer is trying to gain insight into how the candidate thinks and describes his or her thoughts. Therefore, the #1 suggestion for approaching these problems is to communicate your thoughts while you are reasoning through them. Talk aloud about alternative solutions you are considering. Ask questions of the interviewer about the constraints of the problem. If you cannot come up with a solution, explain some option that would get you close. Going back to the polar bear problem, it would probably be enough to understand that the hunter is at the North Pole.

For more tips and great job interview Brain Teaser examples, I recommend the book How to Ace the Brain Teaser Interview.

 

Brain Teasers in the Movies

Some of the most fun Brain Teasers to discuss with friends are those from movies. It’s interesting when someone has seen the movie and remembers the solution, but when you propose it again after some time, he or she does not remember it. Below are some examples of the best movie Brain Teasers (hopefully YouTube won’t remove them).

 

Metro (Retrieve a cap from a bottle)

 

Labyrinth (Which door to knock on?)

 

Die Hard with a Vengeance (How to get exactly 4 gallons of water)

 

Batman TV Series (Top 10 Riddler riddles)

 

Post your favorite Brain Teasers in the comments and good luck on your interview!