There are K pegs. Each peg can hold discs in decreasing order of radius when looked from bottom to top of the peg. There are N discs, which have radius 1 o N. Given the initial configuration of the pegs and the final configuration of the pegs, output the moves required to transform from the initial to final configuration ...
What you see above is part of a sample problem found on Facebook’s Web site. Programmers looking for work at Facebook often start out by submitting code to solve puzzlers like this one. Code that impresses the Facebook crowd earns you a job interview over the phone. If that goes well, you’ll find yourself in Facebook’s Menlo Park, Calif., facilities for an in-person evaluation. Facebook says it has uncovered some of its most-able software engineers just by using its Web site to ask for solutions to programming brain-teasers.
Whatever your opinion of Facebook social media, you have to give that company credit for coming up with an inexpensive way of finding good engineers. Its methods stand in direct contrast to the practice of asking riddlelike questions that have nothing to do with the job at hand, an interviewing technique popularized by Google and adopted by several other high-tech companies.
Employers, though, increasingly seem to be coming around to the idea that responses to off-the-wall questions may say something about an applicant’s quick-wittedness, but don’t really reveal much about how that person will get a job done. So some organizations are now trying to find the real qualities that predict good work performance. And many of them have concluded these qualities have little to do with academic credentials or job resumes.
Engineering employers that still depend on brain-teasers to find technical talent might learn a few things from George Anders, a former Wall Street Journal writer and book author. A lot of traditional talent-scouting systems don’t work, he claims. Anders studied several professions to see how the best employers found new hires who would likely turn into first-rate employees. He summarized his findings in a book called The Rare Find. Two of the groups he examined had an interesting insight: The Teach for America project and the U.‡S. Army Special Forces both looked for evidence of one trait in particular — resilience.
Teach for America sends teachers into low-income communities. It figures educators who find success there must persist in the face of problems that might crush less-committed individuals. So among other things, TFA is on the lookout for applicants who struggled in their first year of college but persevered and eventually earned higher grades year after year.
Similarly, Army Special Forces drill sergeants these days aren’t particularly impressed by candidates who do the most pushups or crank out fast times for two-mile runs. They are more interested in who performs well with little sleep during team problems where it’s important to think like a soldier. Guys who excel at pull-ups are still eliminated from the program if they get moody or hostile when things don’t go their way.
I’d argue that resilience is just as important for many engineering tasks as it is for teaching disadvantaged kids or gaining trust in a remote village. But it doesn’t come up in many job interviews because hiring managers find it easier to pull out a few head-scratcher problems than to spend time making a frank assessment about what a job really entails.
— Leland Teschler, Editor