Please share a thought

I am starting work on a very simple app with Android studio and even if the idea is simple I have no knowledge how to go about it and I am hoping someone can quickly guide me in the right direction :

Purpose is to select elements from a list

ex. I have a list of different combinations ranked from best to worse

1. A B D
2. G B X
3. A G S

I want to give the user the option to select what elements they have for ex. "A D S B" and then my app should select all the possible combinations of those elements
from the list in the best to worse order.

I hope it makes sense and someone can at least tell me if there is a certain algorithm that helps me achieve this. Thank you !

 

OK let me just use the actual terms its for a mobile game and those are legions that can contain 3 heroes. I plan to make a list of all the possible combinations of heroes and rank them from best to worse . The apps job is : the user will give the app all the heroes that he owns in and depending on the choices it will check the list of the possible combinations and show them by rank ( for the user to find it easy to know which 3 heroes he should use and focus on) . I hope this explanation clarifies things .

 

that is also an option but I want to make it as an app a bit more visually pleasing that's why I was asking here