Long ago, I wrote an article about Profiling Java Programs with VisualVM. It can be interesting to analyze code to find performance bottlenecks. But for competitive programming solutions, it’s usually a losing battle. If you choose the wrong algorithm, no amount of micro-optimization will help.
What are ways to optimize programs? My algorithms are strong enough but I am having serious difficulties in optimizations. I wonder how people in Online Judges think so creatively. (answer)
I’m doing most of my writing on Quora this year. For more information, see A Project for 2020.