So i was looking at an example of a function to reverse the bytes of an unsigned 4 byte int

I don't exactly understand how they figured out their shifts? Can someone explain the thought process behind this?

The function works like this: for int x = 0x12345678 it will return 0x78563412.

write out all 4 bytes of x in binary. for each section in the above, underline the result from the original x and watch as it moves.

i haven't done it since i dont care enough to, but that's generally how to solve bit shifting problems unless it's one of those annoying esoteric ones. especially since you already have the solution

Yeah I actually made a picture of it, figured it out thanks!

That's ugly.

here's a much clearer version:


or as an image:


This post was edited by KrzaQ2 on Sep 25 2012 06:21am

Nvm

This post was edited by lopelurag on Sep 25 2012 10:12am