Display Certain code based on Post author

Ok, I am trying to set up a simple ad sharing scheme for my authors with Adsense, so they get a cut depending on how much their posts earn. I want it to when someone views a post by author X, they see adsense code X, author Y, adsense code Y and so on. Im not any good at coding, so I just need to conditions. At the moment I will be doing for two authors, but since I do want to get more writes on board, could it be demonstrated how to modify the code for more display conditions?

I cant seem to find a plugin that does this well, so I want to try this out till the site makes some decent profits so I can pay them on a better system. I guess this will also encourage them to market their posts and take all the marketing pain of my shoulders.