这是一个学生成绩管理系统，其中“I”表示插入，“L”表示浏览，“Q”表示查询，

“E”表示退出，“D”表示删除，“M”表示修改,\"c\"表示统计各分数段人数,\"p\"表示打印.

本程序实现了：

-This is a performance management system for students, "I" to insert said, "L" said View, "Q" said inquiries, "E" from "D" to delete said, "M" said the amendments "c" indicates a statistical fraction of the number of "p" said Print. the program : This is a performance management system for students, "I" to insert said, "L" said View, "Q" said inquiries, "E" from "D" to delete said, "M" said the amendments, "c", said the statistics of the number of scores, "p" said Print. the program :