You didn’t specify a language, so I’ll try and keep this somewhat generic. It’ll be hard though, since it’s a lot easier to express concepts with actual code. Unit tests can be a bit confusing at first. Sometimes it’s not always clear how to test something, or what the purpose of a test is. I … Read more
I prefer the first style, except that I wouldn’t create a variable when there is no need for it. I’d do this: // Style 3 public SomeType aMethod() { if (!guardCondition()) { return null; } SomeType result = new SomeType(); doStuffToResult(result); doMoreStuffToResult(result); return result; }
One way is to use a hierarchy of critical sections. If you ensure that a parent critical section is never entered within one of its children, deadlocks cannot happen. The difficulty is to enforce this hierarchy.
Yes, there is a basic O(1) algorithm. I start with the assumption both people start “ticking” at t=0. I believe the solution should generalize to different starting times, but it isn’t hard to extend from one “free end” of the timeline to two ends. Assume n <= m. Then our timeline looks like this (an … Read more
A linear feedback shift register is pretty simple, as long as you’re comfortable with thinking in binary (or maybe hex, since it’s easy to map between the two). A more complex one is Xorshift, but if you know your bitwise operations, it should be quite possible to work with as well.
There are two main approaches. If you have a set of polygonal shapes, it is possible to create a BSP tree for each shape, then the BSP trees can be merged. From Wikipedia, 1990 Naylor, Amanatides, and Thibault provide an algorithm for merging two bsp trees to form a new bsp tree from the two … Read more
Read this first! This post is to show the possibility rather than endorsing the “everything regex” approach to problem. The author has written 3-4 variations, each has subtle bug that are tricky to detect, before reaching the current solution. For your specific example, there are other better solution that is more maintainable, such as matching … Read more
You probably want to look into Markov Chains as the basics for the bot AI. I wrote something a long time ago (the code to which I’m not proud of at all, and needs some mods to run on Python > 1.5) that may be a useful starting place for you: http://sourceforge.net/projects/benzo/ EDIT: Here’s a … Read more
Think long term maintenance. Keep the code as explicit as possible. Don’t rely on language specific ways to initialize if you don’t have to. Maybe a newer version of the language will work differently? Future programmers will thank you. Management will thank you. Why obfuscate things even the slightest? Update: Future maintainers may come from … Read more
This looks like a classic case of old technology being overlooked – I managed to dig out a copy of Graphics Gems IV from the garage and it looks like Ken Shoemake has not only an algorithm for converting from Euler angles of arbitrary rotation order, but also answers most of my other questions on … Read more