# 1379：6.1（指定等级）

###### 题目描述

如果分数>=best-10,等级为A

如果分数>=best-30,等级为C

其他情况下，等级为F

###### 输入样例
4
40 55 70 58
###### 输出样例
Student 0 score is 40 and grade is C
Student 1 score is 55 and grade is B
Student 2 score is 70 and grade is A
Student 3 score is 58 and grade is B`

 时间上限 内存上限 1000 MS 128 MB