One of the keys to finding a good solution is finding a way to grade it. To enable the grading of solutions, we must establish a set of rules and their weights. Then we analyse a solution based on those rules and grade it.
Here are the rules we established (ordered by importance):

1. A person can only be in one place at a time
   • A professor can only lecture one class at a time (one schedule), unless it's a double discipline
   • A student can only attend one class at a time (one schedule)
2. A class can only happen if there is a professor lecturing it
3. A professor can only lecture a class if he is capable
4. A professor cannot lecture a class on a period he is not avaliable
5. A professor cannot lecture any classes on a semester he is not avaliable
6. There must be at least one set of classes that do not intercept for all disciplines of a given course and semester.
7. A class lectured by a given professor cannot have more students then the professor selected attending it.
8. All probable graduates must be able to graduate.

   For a ideal solution this doesn't mean much if you consider the following rule. This is actually used only by non-ideal solutions

9. A student must be able to attend non intercepting classes of:
   all required disciplines and the n heigher weighted electives he selected (n is the number of electives he wants to attend).