decision tree – Rummy Card Game Bot

in my beginner’s computer science class, we are asked to create an bot for a variant of rummy. It has to make logical moves as it needs to beat other very simple bots. I wanted to know how you would go about coding such program. From what I’ve seen in a few Google searches, people seem to rely heavily on decision trees, but I feel like there must be a more efficient ways of dealing with this kind of problem (without completely ditching the trees). I’m not looking for any code, I’d just like to learn how to address this kind of problem.

Thank you