private static void loadRelationshipFromFile(final String relationship) throws IOException {
		final Scanner in = new Scanner(new File(relationship));
		int count = 0;
		while(in.hasNext()) {
			final String line = in.nextLine();
			final String[] parts = line.split("\t");
			if (parts.length != 2) continue;
			final String sectionId = parts[0];
			final String studentId = parts[1];
			final Section section = sections.get(sectionId);
			final Student student = students.get(studentId);

			if(section!=null && student!=null) {
				section.getStudents().add(student);
				student.getSections().add(section);
			} else
				System.err.println("relationship invalid!");

			count++;
		}
		in.close();
	}