The following “Constraint” need to be considered
1.One teacher can advise many students, one student can be advised by only 1 teacher. Some teacher do not advise students but every students need be advised.
2.Some teacher do not teach in this semester but every subject have to be taught. One teacher can teach many subjects but each subject can be taught by only one teacher.
3.Every student must register in this semester but some subjects were not registered. One student can study many subjects and one subject was studied by many students.
4.Every subjects have schedule. One subject may have one or more that one schedule and one schedule but one schedule belongs to one subject