Random graph theory problem

ProblemEquation.java

import java.util.List;
import java.util.Map;
public class Main {
	interface Level {
		// Pattern matcher
		interface Visitor<P, R> {
			R visitConst(Const c, P p);
			R visitInfinity(P p);
			R visitRef(Reference r, P p);
		}
		<P, R> R accept(Visitor<P, R> visitor, P p);
	}
	record Const(int constant) implements Level {
		@Override public <P, R> R accept(Visitor<P, R> visitor, P p) {
			return visitor.visitConst(this, p);
		}
	}
	record Infinity() implements Level {
		@Override public <P, R> R accept(Visitor<P, R> visitor, P p) {
			return visitor.visitInfinity(p);
		}
	}
	record Reference(Var ref, int lift) implements Level {
		@Override public <P, R> R accept(Visitor<P, R> visitor, P p) {
			return visitor.visitRef(this, p);
		}
	}
	// free means need to be 'solved'
	record Var(boolean canBeInf, int defaultValue, boolean free) {
	}
	record Max(List<Level> levels) {
	}
	enum Ord {
		// <=, >=, ==
		Lt, Gt, Eq
	}
	record Equation(Ord ord, Max lhs, Max rhs) {
	}

  // in the returned map, all keys are 'free', and the Var in the values' are not 'free'
	static Map<Var, Level> solve(List<Equation> equations) {
		// implement
		throw new UnsupportedOperationException();
	}

	public static void main(String... args) {
	}
}