设计一个实用的小型校园信息管理系统，其中涉及到3个主体：学生、教师和课程。教师之间选择的课程互不重复，学生之间选择的课程可以重复。教师的功能可以录入成绩、修改成绩、统计该课程的平均成绩以及显示相关信息。学生的功能除了选择课程外，还可以查询每门课的成绩和自己的平均成绩以及显示相关信息。-Designing a practical small campus information management system, which involves three main: students, teachers and curriculum. Choose between a teacher and do not repeat the curriculum, students choose between courses can be repeated. Teachers can input function results, performance modifications, statistical average grade for the course and display relevant information. Students select courses in addition to the functions, you can also check the results for each course and their grade point average and display relevant information.