Puzzlers series

I guess everyone have been in situation when he/she has written code, which didn't behave as it should. Most of these times, problem was of PEBKAC (problem exists between keyboard and chair) type. Computers (nearly) always do, what they're told to do. Under influence of Java Puzzlers book by Neal Gafter and Joshua Bloch, I've decided to start series of posts to this blog, which would cover situations when program doesn't do what we think it should. At first posts will be mostly in C/C++, but i think more languages will be covered in the future. Posts will be formated, so that you'll see only problem with possible answers. Solution will have font color set to background color, or some close color, so you'd have to highlight block in order to see it. You're more than welcome to add your own puzzlers. Just contact me.