Student Scheduling: Dependent Courses

- suggestions improvements
  - dependent courses constraint do not return a conflict on unassignment of the child course (using an empty enrollment for the course)
  - do not check for dependent courses when computing available values (so a swap can be considered)

Author: tomas-muller

src/org/cpsolver/studentsct/constraint/DependentCourses.java

@@ -47,7 +47,7 @@ public void computeConflicts(Assignment<Request, Enrollment> assignment, Enrollm
         if (value != null && value.getCourse() != null) {
             // check if assigned course has a parent
             Course parent = value.getCourse().getParent();
-            if (parent != null) {
+            if (parent != null && !value.getAssignments().isEmpty()) {
                 // has parent -> check if student has the parent course assigned
                 for (Request request: value.getStudent().getRequests()) {
                     if (request.hasCourse(parent)) { // this request has the parent course

src/org/cpsolver/studentsct/online/selection/SuggestionsBranchAndBound.java

@@ -350,7 +350,7 @@ protected List<Enrollment> values(final Request request) {
             return values;
         if (request instanceof CourseRequest) {
             CourseRequest cr = (CourseRequest) request;
-            values = (cr.equals(iSelectedRequest) ? cr.getAvaiableEnrollments(iAssignment) : cr.getAvaiableEnrollmentsSkipSameTime(iAssignment));
+            values = (cr.equals(iSelectedRequest) ? cr.getAvaiableEnrollments(iAssignment, false) : cr.getAvaiableEnrollmentsSkipSameTime(iAssignment, false));
             if (cr.equals(iSelectedRequest)) {
                 Collections.sort(values, new Comparator<Enrollment>() {
                     @Override