If I was giving that interview, I wouldn't give a shit if you found the optimal solution or not. But if you could spend a high-energy hour with me iterating ove

If I was giving that interview, I wouldn't give a shit if you found the optimal solution or not. But if you could spend a high-energy hour with me iterating over possible solutions, then that signals to me that you're smart, have fortitude, and think outside the box. All qualities I would never hire a candidate without. At the end of the day, companies aren't looking for just PHP programmers or UI designers. They're looking for problem solvers first. I've said this before in other threads, but the fact that you cannot solve a given "puzzle" does not mean that you're definitely a bad candidate, but the fact that you can sure as hell signals that you might be a good one. And any company that's in-demand can afford a few false negatives here and there. A PHP programmer's ability to handle saving a company after being hit with a SQL injection attack is surely going to be correlated with PHP coding tenure and expertise. But that being held constant, it's absolutely going to be much more heavily correlated with general problem solving ability, which - as much as it sucks - tends to be correlated with ability to solve "bullshit interview questions"...