The Monster Database of Tech Interview Puzzles

Maybe you've never interviewed for a tech job or a gig in Silicon Valley. If you haven't, you're really missing out. For some reason, brain teasers are one of the tech world's biggest preoccupations in job interviews. The thinking goes (I guess, maybe that's another brain teaser) that programmers can memorize code snippets and otherwise prepare for traditional interview questions, but if you throw a puzzle at them they'll have to exhibit genuine logic and problem-solving skills. Either they will have these skills or they won't, and that will help you decide whether or not they should have a job.

The problem is that some of these puzzles can be extremely hard, if not impossible. Imagine the pressure of a job interview: Now add to it a question like this:

Four people need to cross a rickety rope bridge to get back to their camp at night. Unfortunately, they only have one flashlight and it only has enough light left for seventeen minutes. The bridge is too dangerous to cross without a flashlight, and it’s only strong enough to support two people at any given time. Each of the campers walks at a different speed. One can cross the bridge in 1 minute, another in 2 minutes, the third in 5 minutes, and the slow poke takes 10 minutes to cross. How do the campers make it across in 17 minutes?

You're supposed to figure that out on the spot?

Enter Michael Pryor's techInterview, a growing database of questions like this with, more importantly, the answers. If you're facing a high-tech job interview any time in the near future, it's a great place to practice your puzzling skills, plus prepare for specific questions that might be popular that week. Don't just hit the home page. The discussion boards have a vast number of additional questions to get your brain jumping, with a special emphasis on programming-based puzzles.

Good luck. Now riddle me this: How many three-cent stamps in a dozen?

Oh, and here's the solution to the rope bridge problem. 

LINK: techInterview