Get Author Count

I would like to display a different format for posts with a single author as opposed to posts with multiple authors. To accomplish this, I’m wondering how I could go about recovering a count of the total numbers of authors assigned to each post. If the total is 1, I would display the single layout style. If it is 2 or greater, I would like to display the list.

I can take care of what I need once I can acquire the total number of assigned authors. Any thoughts?

https://wordpress.org/plugins/co-authors-plus/