能够添加新学生，提示用户新学生学号为多少，如果用户输入已存在的学号，提示用户该学号已存在，请重新输入。入学年份要有校验，即按规定格式输入。学号为每个学生的唯一标识。删除学生，当学生毕业或者转学能删除学生，删除时要有友好提示，即把将要删除的学生展示给用户，让用户确认删除对象，方可删除。如果某一学生信息发生变化，要能够对其进行修改，修改同样要有友好提示，提示用户将要把某条记录修改为什么。

-Be able to add new students, prompts the user to the new number is the number of students, if the user input has been in existence for the school number, prompts the user to the school has been there, please re-enter. School year must be checking that the required input format. Student ID for each student unique identifier. Delete students, when students graduate or transfer students can delete, delete when prompted to have a friendly, that is, to delete the students will be displayed to users, allow users to delete the object to confirm before delete. If a student information changes, to be able to modify, to amend the same to have a friendly reminder prompts the user would have to modify a particular record why.