I agree with others that performance on programming puzzles is not representative of your skill as a developer. However, I'd also like to add that knowing how

I agree with others that performance on programming puzzles is not representative of your skill as a developer. However, I'd also like to add that knowing how to analyze worst case runtime or space with Big O notation is very useful and can make a huge impact on the performance of your application. While reviewing programming puzzles may not be a great use of your time, I would suggest refreshing your knowledge on the Big O complexity of common data structures and algorithms.