public static void changeClass(int studentNum, int periodNum1, int periodNum2)
		{
		Course course1;
		Course course2;
		//Sets course
		if(periodNum1 == 1)
			{
			 course1 = StudentInformationSystem.studentList.get(studentNum - 1).getCourse1();
			}
		else if(periodNum1 == 2)
			{
			 course1 = StudentInformationSystem.studentList.get(studentNum - 1).getCourse2();
			}
		else
			{
			 course1 = StudentInformationSystem.studentList.get(studentNum - 1).getCourse3();
			}
		
		if(periodNum2 == 1)
			{
			 course2 = StudentInformationSystem.studentList.get(studentNum - 1).getCourse1();
			}
		else if(periodNum2 == 2)
			{
			 course2 = StudentInformationSystem.studentList.get(studentNum - 1).getCourse2();
			}
		else
			{
			 course2 = StudentInformationSystem.studentList.get(studentNum - 1).getCourse3();
			}
		
		
		//fills course
		if(periodNum1 == 1)
			{
			StudentInformationSystem.studentList.get(studentNum - 1).setCourse1(course2);
			}
		else if(periodNum1 == 2)
			{
			StudentInformationSystem.studentList.get(studentNum - 1).setCourse2(course2);
			}
		else
			{
			StudentInformationSystem.studentList.get(studentNum - 1).setCourse3(course2);
			}
		
		if(periodNum2 == 1)
			{
			StudentInformationSystem.studentList.get(studentNum - 1).setCourse1(course1);
			}
		else if(periodNum2 == 2)
			{
			StudentInformationSystem.studentList.get(studentNum - 1).setCourse2(course1);
			}
		else
			{
			StudentInformationSystem.studentList.get(studentNum - 1).setCourse3(course1);
			}
		}