👋 I’m new to logic programming and am looking solve a constraint problem that is think is best modeled as a finite domain: • Given a set of mentors and mentees • Each mentee can have a list of mentor preferences • I want to find all solutions to matching mentees with their mentor preferences. • Each mentor can only be a mentor for one mentee I first https://clojurians.slack.com/archives/C0566T2QY/p1647097346744699 with https://gist.github.com/krukow/9ab5a708458e4d3d758032b081a5707a: My thinking was to look at this as a finite domain (translating names to numbers) and using a lvarfor each mentor. By using (fd/distinct (vec lmentors)) I was hoping to solve for “each mentor only gets to have a single mentee”. Problem: As the number of lvars becomes large (say ~40) then running (fd/distinct (vec lmentors)) in core.logic very slow. If I remove this constraint the program finds solutions immediately. Question: I’ve tried to model this in datomic too (local dev). However, I find myself unable to write a query that (a) finds all solutions (a seq of “valid mentee-mentor matchings”); and (b) modeling the solution constraint that each mentor may only appear once in the entire solution set (i.e. something similar to fd/distinct). Is it possible to ask datomic to solve this constraint problem or should I be looking to something else? Data setup: https://gist.github.com/krukow/070c51827fd3da25aa24a01ee7045011