创建学生信息(可以根据学号查找，删除，插入学生信息），保存学生信息 。对学生成绩进行从大到小排序 。输出不及格数超过两科的学生的名单-　　　　To create a student information (according to student number to find, delete, insert student information) and save student information. From largest to smallest sort of student achievement. Output does not pass the list of students over two Division